Graphic designation of the knife switch. Conditional graphic and letter designations of electrical radioelements
GOST 2.702-2011
Group T52
INTERSTATE STANDARD
Unified system for design documentation
RULES FOR IMPLEMENTATION OF ELECTRICAL CIRCUITS
Unified system of design documentation. Rules for presentation of electric schemes
ISS 01.100
OKSTU 0002
Introduction date 2012-01-01
Foreword
The goals, basic principles and basic procedure for carrying out work on interstate standardization are established by GOST 1.0-92 "Interstate standardization system. Basic provisions" and GOST 1.2-2009 "Interstate standardization system. Interstate standards, rules and recommendations for interstate standardization. Rules for development, adoption, application, renewal and cancellation "
Information about the standard
1 DEVELOPED by the Federal State Unitary Enterprise "All-Russian Research Institute of Standardization and Certification in Mechanical Engineering" (FSUE "VNIINMASH"), by the Autonomous Non-Commercial Organization "Research Center of CALS-Technologies" Applied Logistics "(ANO Research Center of CALS-Technologies" Applied Logistics " )
2 INTRODUCED by the Federal Agency for Technical Regulation and Metrology
3 ADOPTED by the Interstate Council for Standardization, Metrology and Certification (Minutes dated May 12, 2011 N 39)
Voted for the adoption of the standard:
Short name of the country according to MK (ISO 3166) 004-97 | Abbreviated name of the national standardization body |
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Azerbaijan | Azstandard |
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Ministry of Economy of the Republic of Armenia |
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Belarus | State Standard of the Republic of Belarus |
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Kazakhstan | Gosstandart of the Republic of Kazakhstan |
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Kyrgyzstan | Kyrgyzstandard |
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Moldova-Standard |
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the Russian Federation | Rosstandart |
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Tajikistan | Tajikstandart |
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Uzbekistan | Uzstandart |
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State Consumer Standard of Ukraine |
4 By order of the Federal Agency for Technical Regulation and Metrology dated August 3, 2011 N 211-st, the interstate standard GOST 2.702-2011 was put into effect as a national standard Russian Federation from January 1, 2012
5 REPLACE GOST 2.702-75
Information on the entry into force (termination) of this standard is published in the index " National standards".
Information about changes to this standard is published in the index "National standards", and the text of the changes is published in the information indexes "National standards". In case of revision or cancellation of this standard, the corresponding information will be published in the information index "National standards"
1 area of use
1 area of use
This standard applies to electrical circuits of products of all industries, as well as electrical circuits of power plants and establishes the rules for their implementation.
Based on this standard, it is allowed, if necessary, to develop standards for the implementation of electrical circuits of products of specific types of equipment, taking into account their specificity.
2 Normative references
This standard uses normative references to the following interstate standards:
GOST 2.051-2006 Unified system for design documentation. Electronic documents. General Provisions
GOST 2.053-2006 Unified system for design documentation. Electronic structure of the product. General Provisions
GOST 2.104-2006 Unified system for design documentation. Basic inscriptions
GOST 2.701-2008 Unified system for design documentation. Scheme. Types and types. General requirements to implementation
GOST 2.709-89 Unified system for design documentation. Conventional designations of wires and contact connections of electrical elements, equipment and sections of circuits in electrical diagrams
GOST 2.710-81 Unified system for design documentation. Alphanumeric designations in electrical circuits
GOST 2.721-74 Unified system for design documentation. Conditional graphic designations in schemes. General use symbols
GOST 2.755-87 Unified system for design documentation. Graphic designations in electrical circuits. Switching devices and contact connections
Note - When using this standard, it is advisable to check the validity of the reference standards in the public information system - on the official website of the Federal Agency for Technical Regulation and Metrology on the Internet or according to the annually published information index "National Standards", which was published as of January 1 of the current year , and according to the relevant monthly information signs published in this year... If the reference standard is replaced (changed), then when using this standard, the replacing (modified) standard should be followed. If the reference standard is canceled without replacement, then the provision in which the reference to it is given applies to the extent not affecting this reference.
3 Terms, definitions and abbreviations
3.1 The following terms are used in this standard with the corresponding definitions:
3.2 The following abbreviations are used in this standard:
ESKD - Unified system for design documentation;
UGO - conditional graphic symbols;
ESI - electronic structure of the product;
KD - design document.
4 Key points
4.1 Electrical diagram - a document containing, in the form of conventional images or designations, the component parts of the product, operating with electrical energy, and their interconnection.
4.2 Electrical diagrams can be made as paper and (or) electronic CD.
4.3 General requirements for implementation, types and types of circuits - according to GOST 2.701.
The rules for constructing conventional alphanumeric designations of elements, devices and functional groups in electrical circuits are in accordance with GOST 2.710.
Note - If the electrical circuit is performed as an electronic CD, you should additionally be guided by GOST 2.051.
4.4 Electrical circuits, depending on the main purpose, are divided into the following types:
- structural;
- functional;
- principled;
- connections;
- connections;
- are common;
- location.
4.5 It is allowed to place explanatory inscriptions, diagrams or tables on the diagram that determine the sequence of processes in time, as well as indicate parameters at characteristic points (values of currents, voltages, shape and magnitude of pulses, mathematical dependencies, etc.).
5 Rules for the execution of schemes
5.1 Rules for the execution of structural diagrams
5.1.1 The block diagram shows all the main functional parts of the product (elements, devices and functional groups) and the main relationships between them.
5.1.2 The functional parts on the diagram are depicted in the form of rectangles or UGO.
5.1.3 The graphical construction of the circuit should provide the best representation of the sequence of interaction of functional parts in the product.
On the lines of relationships, it is recommended to use arrows to indicate the direction of the course of processes occurring in the product.
5.1.4 The diagram should indicate the names of each functional part of the product, if a rectangle is used to designate it.
On the diagram, it is allowed to indicate the type of element (device) and (or) the designation of the document (the main design document, standard, technical conditions), on the basis of which this element (device) is applied.
When depicting functional parts in the form of rectangles, it is recommended to inscribe the names, types and designations inside the rectangles.
5.1.5 With a large number of functional parts, instead of names, types and designations, it is allowed to put down serial numbers to the right of the image or above it, as a rule, from top to bottom in the direction from left to right. In this case, the names, types and designations are indicated in the table placed on the diagram field.
5.2 Rules for the execution of functional diagrams
5.2.1 The functional diagram depicts the functional parts of the product (elements, devices and functional groups) involved in the process illustrated by the diagram, and the relationship between these parts.
5.2.2 The functional parts and the relationship between them on the diagram are depicted in the form of UGO, established in the ESKD standards. Individual functional parts are allowed to be depicted as rectangles.
5.2.3 The graphical construction of the diagram should give the most visual representation of the sequence of processes illustrated by the diagram.
5.2.4 Elements and devices are shown on diagrams in a combined or spaced manner.
5.2.5 With the combined method, the component parts of the elements or devices are shown on the diagram in close proximity to each other.
5.2.6 In the exploded method, the component parts of elements and devices or individual elements of devices are shown on the diagram in different places so that the individual circuits of the product are depicted most clearly.
In an exploded manner, it is allowed to depict all and individual elements or devices.
When executing schemes, it is recommended to use the line method. In this case, the UGO elements or their component parts, included in one chain, are depicted sequentially one after another in a straight line, and individual chains - side by side, forming parallel (horizontal or vertical) lines.
When the scheme is executed in a lowercase way, it is allowed to number the lines with Arabic numerals (see Figure 1).
Picture 1
5.2.7 When depicting elements or devices in a spaced way, it is allowed to place UGO elements or devices made in a combined way on the free field of the circuit. In this case, the elements or devices used in the product are partially depicted in full, indicating the used and unused parts or elements (for example, all contacts of a multi-contact relay).
The conclusions (contacts) of the unused elements (parts) are depicted shorter than the conclusions (contacts) of the used elements (parts) (see Figure 2).
Picture 2
5.2.8 Diagrams are performed in a multi-line or single-line image.
5.2.9 With a multi-line image, each circuit is depicted as a separate line, and the elements contained in these circuits - as separate UGO (see Figure 3 a).
a- multi-line image | b- single line image |
Figure 3
5.2.10 With a single-line representation, circuits performing identical functions are depicted as one line, and identical elements of these circuits - with one UGO (see Figure 3 b).
5.2.11 If necessary, the diagram indicates the electrical circuits. These designations must comply with the requirements of GOST 2.709.
5.2.12 When depicting different functional circuits on the same diagram, it is allowed to distinguish them by their line thickness. In one diagram, it is recommended to use no more than three sizes of lines in thickness. If necessary, the corresponding explanations are placed on the field of the diagram.
5.2.13 To simplify the diagram, it is allowed to merge several electrically unconnected interconnection lines into a group interconnection line, but when approaching the contacts (elements), each interconnection line is depicted as a separate line.
When merging lines of interconnection, each line is marked at the point of merging, and, if necessary, at both ends with symbols (numbers, letters or a combination of letters and numbers) or symbols adopted for electrical circuits (see 5.2.11).
The lines are marked in accordance with the requirements given in GOST 2.721.
Electrical interconnection lines merged into a group interconnection line, as a rule, should not have branches, i.e. any conventional number must occur twice on the line of the group relationship. If branching is necessary, their number is indicated after the serial number of the line through a fractional bar (see Figure 4).
Figure 4
5.2.14 It is allowed, if this does not complicate the scheme, separately shown parts of the elements to be connected by a line of mechanical interconnection, indicating that they belong to one element.
In this case, the reference designations of the elements are affixed at one or both ends of the mechanical interconnection line.
5.2.15 The diagram should indicate:
- for each functional group - the designation assigned to it on the schematic diagram, and (or) its name; if a functional group is depicted as UGO, then its name is not indicated;
- for each device shown in the form of a rectangle - the reference designation assigned to it on the schematic diagram, its name and type and (or) the designation of the document (main design document, standard, technical specifications), on the basis of which this device is applied;
- for each device depicted in the form of a UGO, - the reference designation assigned to it on the schematic diagram, its type and (or) the designation of the document;
- for each element - the reference designation assigned to it on the schematic diagram, and (or) its type.
The designation of the document on the basis of which the device is applied, and the type of element may not be indicated.
It is recommended to write names, types and designations in rectangles.
5.3 Rules for the implementation of schematic diagrams
5.3.1 The schematic diagram depicts all electrical elements or devices necessary for the implementation and control of the installed electrical processes in the product, all electrical interconnections between them, as well as electrical elements (connectors, clamps, etc.) that end the input and output chains.
5.3.2 The diagram is allowed to depict connecting and mounting elements installed in the product for design reasons.
5.3.3 The diagrams are performed for products in the disconnected position.
In technically justified cases, it is allowed to depict individual elements of the circuit in the selected working position with an indication on the field of the diagram of the mode for which these elements are depicted.
5.3.4 Elements and devices, the UGO of which are installed in the ESKD standards, are shown on the diagram in the form of these UGO.
Note - If the UGO is not established by the standards, then the developer performs the UGO in the margins of the diagram and gives explanations.
5.3.5 Elements or devices used in the product in part may not be fully depicted on the diagram, being limited to the depiction of only the parts or elements used.
5.3.6 When performing the schematic diagram, it is allowed to use the provisions specified in 5.2.4-5.2.14.
5.3.7 Each element and (or) device that has an independent schematic diagram and is considered as an element included in the product and shown in the diagram must have a designation (reference designation) in accordance with GOST 2.710.
Devices that do not have independent circuit diagrams and functional groups are recommended to be assigned designations in accordance with GOST 2.710.
5.3.8 Positional designations of elements (devices) should be assigned within the product (installation).
5.3.9 Sequential numbers to elements (devices) should be assigned, starting from one, within a group of elements (devices), which are assigned the same letter reference designation in the diagram, for example,, etc.,,, etc.
5.3.10 Serial numbers should be assigned in accordance with the sequence of elements or devices on the diagram from top to bottom in the direction from left to right.
If necessary, it is allowed to change the sequence of assigning serial numbers depending on the placement of elements in the product, the direction of signal flow or the functional sequence of the process.
When making changes to the schema, the sequence of assigning serial numbers can be changed.
5.3.11 Positional designations are put on the diagram next to the UGO of elements and (or) devices on the right side or above them.
It is allowed to place the reference designation inside the UGO rectangle.
5.3.12 On the diagram of a product, which includes devices that do not have independent circuit diagrams, it is allowed to assign reference designations to elements within each device.
If the product includes several identical devices, then item designations should be assigned within these devices.
Sequential numbers should be assigned to the elements according to the rules established in 5.3.9.
Elements that are not included in the device are assigned reference designations, starting from one, according to the rules established in 5.3.8-5.3.10.
5.3.13 On the diagram of a product, which includes functional groups, reference designations are assigned to elements according to the rules established in 5.3.8-5.3.10, while first assigning reference designations to elements that are not included in functional groups, and then to elements included into functional groups.
If there are several identical functional groups in the product, the item designations assigned in one of these groups should be repeated in all subsequent groups.
The designation of the functional group, assigned in accordance with GOST 2.710, is indicated near the image of the functional group (above or on the right).
5.3.14 When depicted on the diagram of an element or device in a spaced way, the reference designation of an element or device is affixed near each component (see Figure 5).
Combined way of displaying the device | Exploded view of the device |
Figure 5
If the field of the diagram is divided into zones or the diagram is executed in a lowercase way, then to the right of the reference designation or under the designation of each component of an element or device, it is allowed to indicate in brackets the designations of zones or line numbers in which all other component parts of this element or device are shown (see Figure 6).
Figure 6
It is allowed when depicting an element or device on a diagram in a spaced way, the reference designation of each component part of an element or device, as in the combined method, but with an indication for each part of the designations of the terminals (contacts).
5.3.15 When depicting individual elements of devices in different places, the reference designation of the device into which they are included, for example, = A3-C5 - capacitor C5 included in device A3, must be included in the reference designations of these elements.
5.3.16 With the spaced way of displaying a functional group (if necessary, and a combined method), the designation of the functional group should be included in the reference designations of the elements included in this group, for example, T1-C5 - capacitor C5, included in the functional group T1.
5.3.17 With a single-line image about one UGO replacing several UGO of the same elements or devices, indicate the reference designations of all these elements or devices.
If identical elements or devices are not found in all circuits shown in a single line, then to the right of the reference designation or under it in square brackets indicate the designations of the circuits in which these elements or devices are located (see Figure 3).
5.3.18 On the schematic diagram, all elements and devices that are part of the product and shown in the diagram must be uniquely identified.
The data on the elements should be recorded in the list of elements, drawn up in the form of a table in accordance with GOST 2.701. In this case, the connection of the list with the UGO of elements should be carried out through the reference designations.
For electronic documents, the list of elements is drawn up as a separate document.
When the elements of the scheme are included in the ESI (GOST 2.053), the list of elements drawn up in accordance with GOST 2.701 is recommended to be obtained from it in the form of a report.
It is allowed in some cases, established by the standards, to place all information about the elements near the UGO.
5.3.19 In case of a complex entry, for example, when a device that does not have an independent circuit diagram includes one or more devices that have independent circuit diagrams and (or) functional groups, or if a functional group includes one or more devices, etc. then in the list of elements in the "Name" column, before the name of devices that do not have independent circuit diagrams and functional groups, it is allowed to put down serial numbers (i.e., like the designation of sections, subsections, etc.) within the entire product diagram (see figure 7). Functional units or devices (including those made on a separate board) are marked with dashed lines. If on the diagram in the reference designation of an element a reference designation of a device or designation of a functional group is included, then in the list of elements in the column "Designation" indicate the reference designation of an element without a reference designation of a device or designation of a functional group.
Figure 7
5.3.20 When indicating the values of resistors and capacitors near the UGO (see Figure 8), it is allowed to use a simplified method of designating units of quantities:
- for resistors:
from 0 to 999 Ohm - without indication of units of values,
from 1 10 to 999 10 Ohm - in kilo-ohms with the designation of the unit of values by the lowercase letter k,
from 1 10 to 999 10 Ohm - in megaohms with the designation of the unit of quantities by the capital letter M,
over 1 · 10 Ohm - in gigaohms with the designation of the unit of quantities by the capital letter G;
- for capacitors:
from 0 to 9999 12 F * - in picofarads without specifying the unit of values,
________________
* The text of the document corresponds to the original. - Note from the manufacturer of the database.
from 1 · 10 to 9999 · 10 F - in microfarads with the designation of the unit of values in lowercase letters mk.
Figure 8
5.3.21 The diagram should indicate the designations of the outputs (contacts) of the elements (devices) applied to the product or installed in their documentation.
If in the design of the element (device) and in its documentation the designations of the conclusions (contacts) are not indicated, then it is allowed to conditionally assign them designations on the diagram, repeating them in the future in the corresponding design documents.
With the conditional assignment of designations to the conclusions (contacts), a corresponding explanation is placed on the diagram field.
When depicting several identical elements (devices) on the diagram, the designation of the conclusions (contacts) is allowed to be indicated on one of them.
With the spaced-apart method of displaying the same elements (devices), the designations of the terminals (contacts) indicate on each component part of the element (device).
To distinguish the designations of terminals (contacts) from other designations (designations of circuits, etc.) on the diagram, it is allowed to write the designations of the terminals (contacts) with a qualifying symbol in accordance with the requirements of GOST 2.710.
5.3.22 When depicting an element or device in a spaced way, an explanatory inscription is placed near one component of the product or on the diagram field near the image of an element or device made in a combined way.
5.3.23 It is recommended to indicate on the diagram the characteristics of the input and output circuits of the product (frequency, voltage, current, resistance, inductance, etc.), as well as the parameters to be measured at control contacts, sockets, etc.
If it is impossible to indicate the characteristics or parameters of the input and output circuits of the product, then it is recommended to indicate the name of the circuits or controlled quantities.
5.3.24 If the product is deliberately intended to operate only in a specific product (installation), then it is allowed to indicate the addresses of the external connections of the input and output circuits of this product on the diagram. The address must ensure unambiguous connection, for example, if the output contact of the product is to be connected to the fifth contact of the third connector of the device, then the address must be written as follows: = 3: 5.
It is allowed to indicate the address in general form, if the uniqueness of the connection is ensured, for example, "Device A".
5.3.25 The characteristics of the input and output circuits of the product, as well as the addresses of their external connections, are recommended to be recorded in tables placed instead of the UGO of input and output elements - connectors, boards, etc. (see figure 9).
Figure 9
Above the table, it is allowed to indicate the UGO contact - a socket or a pin.
Tables can be executed in an exploded manner.
The order of arrangement of contacts in the table is determined by the convenience of constructing the circuit.
It is allowed to place tables with circuit characteristics if there are input and output elements on the UGO circuit - connectors, boards, etc. (see figure 10).
Figure 10
It is recommended to place similar tables on the lines depicting input and output circuits and not ending on the diagram with connectors, boards, etc. In this case, reference designations are not assigned to tables.
Notes (edit)
1 If there are several tables on the diagram, it is allowed to give the head of the table only in one of them.
2 In the absence of the characteristics of the input and output circuits or the addresses of their external connection, the table does not give a column with these data.
If necessary, it is allowed to enter additional columns into the table.
3 It is allowed to put down in the column "Cont." several consecutive contact numbers in case they are interconnected. The contact numbers are separated from each other by a comma.
5.3.26 When multi-pin connectors are shown on the diagram, it is allowed to use UGOs that do not show individual contacts (GOST 2.755).
Connector pin connection information is specified in one of the following ways:
- near the image of the connectors, on the free field of the circuit or on subsequent sheets of the circuit, tables are placed in which the connection address [circuit designation is indicated (see Figure 11 a) and (or) the reference designation of the elements connected to this contact (see Figure 11 b)].
a- a table placed on a free field of the scheme or on subsequent sheets of the scheme | b- a table placed near the connector image |
Figure 11
If necessary, the table indicates the characteristics of the circuits and the addresses of external connections (see Figure 11 a).
If tables are placed on the schematic field or on subsequent sheets, then they are assigned the reference designations of the connectors to which they are composed.
in the column "Cont." - connector pin number. Contact numbers are written in ascending order,
in the "Address" column - the circuit designation and (or) the reference designation of the elements connected to the contacts,
in the "Chain" column - the characteristics of the circuit,
in the "External address" column - the address of the external connection;
- connections with connector contacts are depicted in a spaced manner (see Figure 12).
Figure 12
Notes (edit)
1 Dots connected by a dashed line to a connector indicate connections to the corresponding pins on that connector.
2 If necessary, the characteristics of the circuits are placed on the free field of the circuit above the continuation of the interconnection lines.
5.3.27 When the elements are shown on the diagram, the parameters of which are selected during regulation, asterisks (for example *) are put down near the reference designations of these elements on the diagram and in the list of elements, and a footnote is placed on the field of the diagram: "* Select during regulation".
The list should record the elements, the parameters of which are closest to the calculated ones.
The permissible limit values of the parameters of the elements during selection are indicated in the list in the "Note" column.
If the parameter selected during regulation is provided by the elements different types, then these elements are listed in the technical requirements on the circuit field, and the following data are indicated in the columns of the list of elements:
in the column "Name" - the name of the element and the parameter closest to the calculated one;
in the column "Note" - a link to the corresponding paragraph technical requirements and admissible limit values of parameters during selection.
5.3.28 If a parallel or series connection is made to obtain a certain value of a parameter (capacitance or resistance of a certain value), then in the list of elements in the column "Notes" indicate the total (total) parameter of the elements (for example, 151 kΩ).
5.3.29 When depicting a device (or devices) in the form of a rectangle, it is allowed to place tables with characteristics of input and output circuits in the rectangle instead of the UGO of input and output elements (see Figure 13), and outside the rectangle it is allowed to place tables indicating the addresses of external connections (see .Figure 14).
Figure 13
Figure 14
If necessary, it is allowed to enter additional columns into the tables.
Each table is assigned a reference designation of the element, instead of which UGO it is placed.
In the table instead of the word "Cont." it is allowed to place a conventional graphic designation of the connector contact (see Figure 14).
On the product diagram in rectangles depicting devices, it is allowed to place structural or functional diagrams devices or completely or partially repeat their schematic diagrams.
The elements of these devices are not recorded in the list of elements.
If the product includes several identical devices, then it is recommended to place the device diagram on a free field of the product diagram (and not in a rectangle) with the appropriate inscription, for example, "Diagram of A1-A4 blocks", or when such a block first appears, open its diagram, and then designate similar blocks with rectangles with the corresponding letter designation.
5.3.30 On the field of the diagram, it is allowed to place instructions on the brands, sections and colors of wires and cables ( stranded wires, electrical cords), which must be used to connect the elements, as well as instructions on specific requirements for electrical installation of this product.
5.4 Rules for the execution of connection diagrams
5.4.1 The connection diagram should show all devices and elements that make up the product, their input and output elements (connectors, boards, clamps, etc.), as well as the connections between these devices and elements.
5.4.2 Devices and elements in the diagram depict:
- devices - in the form of rectangles or simplified external outlines;
- elements - in the form of UGO, rectangles or simplified external outlines.
When depicting elements in the form of rectangles or simplified external outlines, it is allowed to place UGO elements inside them.
Input and output elements are depicted as UGO.
It is allowed to depict input and output elements according to the rules established in 5.3.25, 5.3.26 and 5.3.29.
5.4.3 The location of the graphic designations of devices and elements on the diagram should approximately correspond to the actual placement of elements and devices in the product.
The arrangement of images of input and output elements or outputs within graphic symbols and devices or elements should approximately correspond to their actual placement in the device or element.
It is allowed on the diagram not to reflect the arrangement of devices and elements in the product if the diagram is performed on several sheets or the placement of devices and elements at the place of operation is unknown.
5.4.4 The elements used in part in the product may not be fully depicted on the diagram, being limited to the depiction of only the parts used.
5.4.5 On the diagram, near the graphic designations of devices and elements, indicate the reference designations assigned to them on the circuit diagram.
It is allowed to indicate its name, type and (or) designation of the document, on the basis of which the device is applied, near or inside the graphic designation of the device.
5.4.6 The diagram should indicate the designations of the outputs (contacts) of the elements (devices) applied to the product or installed in their documentation.
If the designations of the input and output elements (outputs) are not indicated in the design of a device or element and in its documentation, then it is allowed to conditionally assign designations to them on the diagram, repeating them in the future in the corresponding design documents.
With the conditional assignment of designations to the input and output elements (outputs), a corresponding explanation is placed on the circuit field.
When depicting several identical pin designations on the diagram, it is allowed to indicate on one of them (for example, the pinout of electrovacuum devices).
5.4.7 Devices and elements with the same external connections are allowed to be shown on the diagram indicating the connection for only one device or element.
5.4.8 Devices with independent schemes connections, it is allowed to depict on the product diagram without showing the connection of wires and cable cores (stranded wires, electrical cords) to the input and output elements.
5.4.9 When depicted on the diagram of connectors, it is allowed to use UGOs that do not show individual contacts (GOST 2.755).
In this case, tables indicating the connection of contacts are placed near the image of the connector, on the diagram field or on subsequent sheets of the diagram (see Figure 15).
Figure 15
When tables are placed in the diagram field or on subsequent sheets, they are assigned the reference designators of the connectors, in addition to which they are composed.
It is allowed to enter additional columns in the table (for example, wire data).
If a bundle (cable - stranded wire, electrical cord, group of wires) connects the same contacts of the connectors, then it is allowed to place the table near one end of the image of the bundle (cable - stranded wire, electrical cord, group of wires).
If information about the connection of contacts is given in the table of connections, then tables indicating the connection of contacts in the diagram may not be placed.
5.4.10 On the product diagram, inside rectangles or simplified external outlines depicting devices, it is allowed to depict their structural, functional or principle diagrams.
5.4.11 In the absence of a schematic diagram of the product on the connection diagram, designations are assigned to devices, as well as to elements that are not included in the schematic diagrams of the component parts of the product, according to the rules established in 5.3.7-5.3.11, and they are recorded in the list of elements.
5.4.12 On the connection diagram of the product, it is allowed to show the external connections of the product according to the rules established in 5.5.8, 5.5.9.
5.4.13 Wires, groups of wires, bundles and cables (stranded wires, electrical cords) should be shown in the diagram with separate lines. The thickness of the lines depicting wires, bundles and cables (stranded wires, electrical cords) in the diagrams should be from 0.4 to 1 mm.
To simplify the outline of the diagram, it is allowed to twist individual wires or cables (stranded wires, electrical cords), going in the same direction in the diagram, into a common line.
When approaching the contacts, each wire and core of the cable (stranded wire, electrical cord) is depicted as a separate line.
Lines depicting wires, groups of wires, harnesses and cables (stranded wires, electrical cords) are allowed, do not lead or break them near the connection points if their image makes it difficult to read the diagram.
In these cases, on the diagram near the connection points (see Figure 16) or in the table on the free field of the diagram (see Figure 17), place information in an amount sufficient to ensure an unambiguous connection.
Picture 16 Picture 17
5.4.14 On the diagram of a product, which includes multi-contact elements, lines representing bundles (cables - stranded wires, electrical cords, groups of wires) can only be brought to the contour of the graphic designation of the element, without showing the connection to the contacts.
In this case, instructions on connecting wires or cable cores (stranded wire, electrical cord) to the contacts are given in one of the following ways:
- at the contacts, show the ends of lines representing wires or cable cores (stranded wire, electrical cord), and indicate their designations. The ends of the lines are directed towards the corresponding bundle, cable (stranded wire, electrical cord), group of wires (see Figure 18);
- at the image of a multi-contact element, place a table indicating the connection of contacts. The table is connected with a leader line with the corresponding bundle, cable (stranded wire, electric cord), a group of wires (see Figure 19).
Figure 18
Figure 19
5.4.15 The introductory elements through which the wires pass (a group of wires, bundles, cables - stranded wires, electrical cords) are depicted in the form of UGO, established in the ESKD standards.
Bushings, sealed glands, glands, contacts and holders, soldered in printed circuit board, depicted in the form of UGO, shown in Figure 20.
a- a line representing a wire (group of wires, harness, cable - stranded wire, electrical cord)
Figure 20
5.4.16 The diagram should indicate the designations of the introductory elements applied to the product.
If the designations of the input elements are not indicated in the design of the product, then it is allowed to conditionally assign them designations on the connection diagram, repeating them in the corresponding design documentation. In this case, the necessary explanations are placed on the field of the diagram.
5.4.17 Solid wires, bundles, cables (stranded wires, electrical cords) should be designated with serial numbers within the product.
Wires, harnesses, cables (stranded wires, electrical cords) should be numbered separately. In this case, the wires included in the bundle are numbered within the bundle, and the cores of the cable (stranded wire, electrical cord) are numbered within the cable (stranded wire, electrical cord).
Notes (edit)
1 Continuous numbering of all wires and cores of cables (stranded wires, electrical cords) within the product is allowed.
2 Sequential numbering of individual wires, bundles and cables (stranded wires, electrical cords) within the product is allowed. In this case, the wires included in the bundle are numbered within the bundle, and the cores of the cable (stranded wire, electrical cord) are numbered within the cable (stranded wire, electrical cord).
3 It is allowed not to designate bundles, cables (stranded wires, electrical cords) and individual wires if the product for which the circuit is made is included in the complex and the designations for bundles, cables (stranded wires, electrical cords) and wires will be assigned within the entire complex.
4 It is allowed to assign designations to wire groups.
5.4.18 If, on the schematic diagram, electrical circuits are assigned designations in accordance with GOST 2.709, then all single-core wires, cable cores (stranded wires, electrical cords) and harness wires are assigned the same designations. In this case, bundles and cables (stranded wires, electrical cords) are designated in accordance with the requirements of 5.4.17.
5.4.19 On the diagram, using an alphabetic (alphanumeric) designation, it is allowed to determine the functional belonging of a wire, bundle or cable (stranded wire, electrical cord) to a specific complex, room or functional circuit.
The letter (alphanumeric) designation is placed in front of the designation of each wire, bundle, cable (stranded wire, electrical cord), separating it with a hyphen. In this case, the letter (alphanumeric) designation is included in the designation of each wire, bundle and cable (stranded wire, electrical cord).
It is allowed not to put a hyphen in the designation, if this does not introduce ambiguity into the reading of the diagram.
If all the wires, bundles, cables (stranded wires, electrical cords) shown in the diagram belong to the same complex, room or functional circuit, then the letter (alphanumeric) designation is not put down, but a corresponding explanation is placed on the diagram field.
5.4.20 The numbers of wires and cores of cables (stranded wires, electrical cords) on the diagram are usually placed near both ends of the images.
The numbers of cables (stranded wires, electrical cords) are placed in circles placed in the gaps in the images of cables (stranded wires, electrical cords) near the branching points of the cores.
The harness numbers are affixed on the shelves of the leader lines near the branching points of the wires.
Wire group numbers are placed near the leader lines.
Notes (edit)
1 When designating cables (stranded wires, electrical cords) in accordance with the requirements of 5.4.19, as well as with a large number of cables (stranded wires, electrical cords) running in one direction in the diagram, cable numbers (stranded wires, electrical cords) are allowed put down lines without a circle in the gap.
2 When depicted on the diagram of wires, harnesses and cables (stranded wires, electrical cords) of long length, numbers are affixed at intervals determined by the convenience of using the diagram.
5.4.21 The diagram should indicate:
- for cables (stranded wires, electrical cords) recorded in the specification as material, - the brand, number and cross-section of cores and, if necessary, the number of occupied cores. The number of occupied cores is indicated in a rectangle placed to the right of the cable data designation (stranded wire, electrical cord);
- for bundles, cables and wires manufactured separately, - designation of the main design document.
The diagram shows the characteristics of the input and output circuits of devices and elements or other initial data necessary for the selection of specific wires and cables (stranded wires, electrical cords), if during the development of the complex circuit data on wires and cables (stranded wires, electrical cords) cannot be determined.
It is recommended to indicate the characteristics of the input and output circuits in the form of tables (see 5.3.25), placed instead of the conventional graphic symbols of the input and output elements.
5.4.22 Data (brand, section, etc.) about wires and cables (stranded wires, electrical cords) are indicated near the lines representing wires and cables (stranded wires, electrical cords).
In this case, it is allowed not to assign designations to wires and cables (stranded wires, electrical cords).
When specifying data on wires and cables (stranded wires, electrical cords) in the form of symbols, these designations are deciphered on the diagram field.
The same brand, cross-section and other data on all or most of the wires and cables (stranded wires, electrical cords) are allowed to be indicated on the diagram field.
5.4.23 If the connection points are not indicated on the diagram (for example, individual contacts are not shown in the image of connectors) or it is difficult to find the points of connection of wires and cable cores (stranded wire, electrical cord), then data on wires, bundles and cables (stranded wires, electrical cords) and the addresses of their connections are summarized in a table called the "Connection Table". The connection table should be placed on the first sheet of the diagram or executed as an independent document.
The connection table, placed on the first sheet of the diagram, is usually located above the title block. The distance between the table and the title block must be at least 12 mm.
The continuation of the table of connections is placed to the left of the main inscription, repeating the head of the table.
The connection table in the form of an independent document is performed in A4 format. The main inscription and additional columns to it are performed in accordance with GOST 2.104 (forms 2 and 2a).
5.4.24 The form of the connection table is chosen by the designer of the circuit, depending on the information that needs to be placed on the circuit (see Figure 21).
Figure 21
The following data are indicated in the columns of the tables:
in the column "Wire designation" - the designation of a single-core wire, cable core (stranded wire, electrical cord) or wire harness;
in the columns "Where it comes from", "Where it comes from" - conventional alphanumeric designations of the connected elements or devices;
in the "Connections" column - conventional alphanumeric designations of the connected elements or devices, separating them with a comma;
in the "Wire data" column:
- for a single-core wire - brand, cross-section and, if necessary, color in accordance with the document on the basis of which it is used;
- for a cable (stranded wire, electric cord) recorded in the specification as a material - the brand, cross-section and number of cores in accordance with the document on the basis of which the cable (stranded wire, electric cord) is used;
in the "Note" column - additional clarifying data.
Notes (edit)
2 Columns are allowed to be divided into subgraphs.
5.4.25 When filling out the connection table, the following order should be followed:
- when making connections separate wires the wires are recorded in the table in ascending order of the numbers assigned to them;
- when making connections with wires of bundles or cores of cables (stranded wires, electrical cords), before recording the wires of each bundle or cores of each cable (stranded wire, electrical cord), place a heading, for example: "Bundle 1" or "Bundle ABVG.XXXXXX.032" ; "Cable 3" or "Cable ABVG.XXXXXX.042"; "Wire 5". The wires of the bundle or the cores of the cable (stranded wire, electrical cord) are recorded in ascending order of the numbers assigned to the wires or cores;
- when making connections with individual wires, wiring harnesses and cables (stranded wires, electrical cords), the individual wires (without a header) are first recorded in the connection table, and then (with the corresponding headings) wiring harnesses and cables (stranded wires, electrical cords).
If insulating tubes, shielding braids, etc. are to be put on individual wires, then the corresponding instructions are placed in the "Note" column. It is allowed to place these instructions on the diagram field.
NOTE When using the wiring diagram for wiring only, a different notation order is allowed if specified in the industry standard.
5.4.26 On the connection diagram near both ends of the lines depicting individual wires, wires of bundles and cores of cables (stranded wires, electrical cords), it is allowed to indicate the address of the connections. In this case, no connection table is made. It is allowed not to assign designations to wires.
5.4.27 On the field of the scheme above the main inscription, it is allowed to place the necessary technical instructions, For example:
- requirements on the inadmissibility of joint laying of some wires, harnesses and cables (stranded wires, electrical cords);
- the minimum allowable distance between wires, bundles and cables (stranded wires, electrical cords); data on the specificity of laying and protecting wires, harnesses and cables (stranded wires, electrical cords), etc.
5.5 Rules for the implementation of connection diagrams
5.5.1 The connection diagram should show the product, its input and output elements (connectors, clamps, etc.) and the ends of wires and cables (stranded wires, electrical cords) connected to them external mounting, near which data on the connection of the product is placed [characteristics of external circuits and (or) addresses].
5.5.2 The product on the diagram is depicted in the form of a rectangle, and its input and output elements - in the form of a UGO.
It is allowed to depict the product in the form of simplified external outlines. In this case, the input and output elements are depicted in the form of simplified external outlines.
5.5.3 The placement of images of input and output elements inside the graphic designation of the product should approximately correspond to their actual placement in the product.
5.5.4 The schematic should indicate the reference designations of the input and output elements assigned to them on the schematic diagram of the product.
5.5.5 Input elements (for example, glands, sealed glands, bushings, contacts and holders soldered into a printed circuit board), through which wires or cables (stranded wires, electrical cords, coaxial cables) pass, are shown in the diagram according to the rules established in 5.4.15.
5.5.6 The diagram should indicate the designations of the input, output or output elements applied to the product.
If the designations of the input, output and output elements are not indicated in the product design, then it is allowed to conditionally assign designations to them on the diagram, repeating them in the corresponding design documentation. In this case, the necessary explanations are placed on the field of the diagram.
5.5.7 On the diagram near the UGO of the connectors to which the wires and cables are connected (stranded wires, electrical cords), it is allowed to indicate the names of these connectors and (or) the designations of the documents on the basis of which they are applied.
5.5.8 Wires and cables (stranded wires, electrical cords) should be shown on the diagram with separate lines.
5.5.9 If necessary, the grades, cross-sections, colors of wires, as well as brands of cables (stranded wires, electrical cords), the number, cross-section and occupancy of the conductors are indicated on the diagram.
When specifying brands, sections and colors of wires in the form of symbols on the diagram field, these symbols are deciphered.
5.6 Rules for the implementation of general schemes
5.6.1 The general diagram shows the devices and elements included in the complex, as well as wires, bundles and cables (stranded wires, electrical cords) connecting these devices and elements.
5.6.2 Devices and elements on the diagram are depicted as rectangles. It is allowed to depict elements in the form of UGO or simplified external outlines, and devices - in the form of simplified external outlines.
The location of the graphic designations of devices and elements on the diagram should approximately correspond to the actual placement of elements and devices in the product.
It is allowed on the diagram not to reflect the location of devices and elements in the product, if their placement at the place of operation is unknown.
In these cases, graphic designations of devices and elements should be located so as to ensure simplicity and clarity of display. electrical connections between them.
5.6.3 On the graphic designations of devices and elements, input, output and input elements are depicted according to the rules established in 5.4.9, 5.4.15.
The location of the UGO of input, output and input elements inside the images of devices and elements should approximately correspond to their actual placement in the product. If, to ensure clarity in showing the connections, the location of the graphic designations of these elements does not correspond to their actual placement in the product, then an appropriate explanation should be placed on the diagram field.
5.6.4 The diagram should indicate:
- for each device or element depicted in the form of a rectangle or simplified external outline, - their name and type and (or) designation of the document on the basis of which they are applied;
- for each element shown in the form of UGO - its type and (or) document designation.
5.6.5 Devices and elements grouped into posts and (or) rooms are recommended to be recorded in the list by posts and (or) rooms.
5.6.6 The diagram should indicate the designations of the input, output and input elements applied to the product.
If the designations of input, output and input elements are not indicated in the product design, then it is allowed to conditionally assign designations to these elements on the diagram, repeating them in the corresponding design documentation. In this case, the necessary explanations are placed on the field of the diagram.
5.6.7 On the diagram, it is allowed to indicate the designations of the documents of the connectors on the shelves of the leader lines, as well as the number of contacts of the connectors, using their following UGO (see Figure 22).
Figure 22
5.6.8 Wires, bundles and cables (stranded wires, electrical cords) should be shown on the diagram with separate lines and marked separately with serial numbers within the product.
Continuous numbering of wires, bundles and cables (stranded wires, electrical cords) within the product is allowed if the wires included in the bundles are numbered within each bundle.
If on the schematic diagram the electrical circuits are assigned designations in accordance with GOST 2.709, then all single-core wires, cable cores (stranded wires, electrical cords) and harness wires are assigned the same designations.
5.6.9 If the product for which the circuit is being developed includes several complexes, then single-core wires, cables (stranded wires, electrical cords) and bundles should be numbered within each complex.
The belonging of a single-core wire, bundle, cable (stranded wire, electrical cord) to a specific complex is determined using an alphabetic (alphanumeric) designation placed in front of the number of each single-core wire, bundle and cable (stranded wire, electrical cord) and separated by a hyphen.
5.6.10 It is allowed on the diagram, using an alphabetic (alphanumeric) designation, to determine the belonging of a wire, bundle or cable (stranded wire, electrical cord) to certain rooms or functional circuits according to the rules established in 5.4.19.
5.6.11 The numbers of single-core wires in the diagram are affixed near the ends of the images; numbers of single-core short wires, which are clearly visible on the diagram, are allowed to be placed near the middle of the images.
5.6.12 The numbers of cables (stranded wires, electrical cords) are put in circles placed in the gaps in the images of cables (stranded wires, electrical cords).
Note - When designating cables (stranded wires, electrical cords) in accordance with the requirements of 5.6.9, 5.6.10, designations are not inscribed in a circle.
5.6.13 The harness numbers are put on the shelves of the leader lines.
5.6.14 In the diagram, near the image of single-core wires, bundles and cables (stranded wires, electrical cords), indicate the following data:
- for single-core wires - brand, cross-section and, if necessary, color;
- for cables (stranded wires, electrical cords) recorded in the specification as material - brand, number and cross-section of conductors;
- for wires, cables and bundles made according to drawings - designation of the main design document.
If, during the development of the circuit, the data on the wires and cables (stranded wires, electrical cords) laid during installation cannot be determined, then the diagram provides appropriate explanations indicating the initial data necessary for the selection of specific wires and cables (stranded wires, electrical cords ).
With a large number of connections, it is recommended to write down the specified information in the list of wires, harnesses and cables (stranded wires, electrical cords).
5.6.15 The list of wires, bundles and cables (stranded wires, electrical cords) (see Figure 23) is placed on the first sheet of the diagram, as a rule, above the main inscription or in the form of subsequent sheets.
Figure 23
The following data are indicated in the columns of the list:
in the column "Designation" - the designation of the main design document of the wire, cable (stranded wire, electrical cord), bundle, made according to the drawings;
in the "Note" column - cables (stranded wires, electric cords) supplied with the complex or laid during its installation.
Cables (stranded wires, electrical cords) laid during installation may not be included in the list.
5.6.16 The general scheme, if possible, should be carried out on one sheet. If the diagram, due to the complexity of the product, cannot be performed on one sheet, then:
- on the first sheet, the product as a whole is drawn, depicting posts and (or) premises with conventional outlines and showing the connections between posts and (or) premises;
- inside the conventional outlines of posts and (or) premises, only those devices and elements are depicted to which wires and cables (stranded wires, electrical cords) connecting the posts and (or) premises are connected;
- on other sheets, completely draw diagrams of individual posts and (or) premises or groups of posts and (or) premises;
- general scheme each complex is performed on a separate sheet if the product includes several complexes.
5.7 Rules for the implementation of layouts
5.7.1 The layout diagram depicts the component parts of the product, and, if necessary, the connection between them - the structure, room or area on which these component parts will be located.
5.7.2 The component parts of the product are depicted in the form of simplified external outlines or conventional graphic symbols.
5.7.3 Wires, groups of wires, bundles and cables (stranded wires, electrical cords) are depicted as separate lines or simplified external outlines.
5.7.4 The location of the graphic designations of the component parts of the product on the diagram should approximately correspond to the actual placement in the structure, room, on the ground.
5.7.5 When performing the layout, it is allowed to apply different ways constructions (axonometry, plan, conditional development, section of the structure, etc.).
5.7.6 The diagram should indicate:
- for each device or element depicted in the form of a simplified external outline, their name and type and (or) the designation of the document on the basis of which they are applied;
- for each element shown in the form of a conventional graphic designation - its type and (or) designation of the document.
With a large number of devices and elements, it is recommended to record this information in the list of elements.
In this case, reference designations are placed near the graphic designations of devices and elements.
Electronic text of the document
prepared by JSC "Kodeks" and verified by:
official publication
M .: Standartinform, 2011
Reading diagrams is impossible without knowledge of conventional graphic and letter designations of elements. Most of them are standardized and described in regulatory documents. Most of them were published in the last century, and only one new standard was adopted, in 2011 (GOST 2-702-2011 ESKD. Rules for the implementation of electrical circuits), so sometimes a new element base is designated according to the principle "how who came up with it." And this is the difficulty of reading the diagrams of new devices. But, in general, the symbols in electrical circuits are described and are well known to many.
On the diagrams, two types of designations are often used: graphic and letter, and denominations are also often affixed. From this data, many can immediately tell how the circuit works. This skill develops over years of practice, but first you need to understand and remember the symbols in electrical circuits. Then, knowing the work of each element, you can imagine the end result of the device.
Different diagrams usually require different elements to compose and read. There are many types of circuits, but in electrics they are usually used:
There are many other types of electrical circuits, but they are not used in home practice. An exception is the route of the passage of cables through the site, the supply of electricity to the house. This type of document will definitely be needed and useful, but it is more of a plan than a diagram.
Basic images and functional signs
Switching devices (switches, contactors, etc.) are based on contacts of different mechanics. There are make, break, changeover contacts. The closing contact in the normal state is open; when it is put into the operating state, the circuit is closed. The normally open contact is closed, and under certain conditions it is triggered to open the circuit.
The changeover contact can be two or three position. In the first case, one chain works, then another. The second has a neutral position.
In addition, contacts can perform different functions: contactor, disconnector, circuit breaker, etc. All of them also have a conventional designation and are applied to the corresponding contacts. There are functions that only moving contacts perform. They are shown in the photo below.
Basic functions can only be performed by fixed contacts.
Single-line diagram symbols
As already mentioned, only the power part is indicated on single-line diagrams: RCDs, automatic machines, difavtomats, sockets, knife switches, switches, etc. and connections between them. The designations of these conventional elements can be used in the diagrams of electrical panels.
The main feature of graphic symbols in electrical circuits is that devices that are similar in principle of operation differ in some trifle. For example, an automatic circuit breaker and a circuit breaker differ only in two small details - the presence / absence of a rectangle on the contact and the shape of the icon on a fixed contact, which reflect the functions of these contacts. The contactor differs from the designation of the breaker only in the shape of the icon on the fixed contact. Very little difference, but the device and its functions are different. All these little things must be looked at and memorized.
There is also a slight difference between the symbols of the RCD and the differential machine. It is also only in the functions of movable and fixed contacts.
Roughly the same is the case with the coils of relays and contactors. They look like a rectangle with small graphic additions.
In this case, it is easier to remember, since there are rather serious differences in appearance additional icons. It's so simple with a photo relay - the rays of the sun are associated with arrows. The impulse relay is also quite easy to distinguish by the characteristic shape of the sign.
A bit easier with bulbs and connections. They have different "pictures". A detachable connection (such as a socket / plug or a socket / plug) looks like two brackets, and a collapsible one (like a terminal block) looks like circles. Moreover, the number of pairs of checkmarks or circles indicates the number of wires.
Image of tires and wires
In any scheme, connections befitting and for the most part they are made with wires. Some connections are buses - more powerful conductive elements from which taps can extend. Wires are indicated by a thin line and branch / connection locations are indicated by dots. If there are no points, this is not a connection, but an intersection (no electrical connection).
There are separate images for buses, but they are used if you need to graphically separate them from communication lines, wires and cables.
On wiring diagrams, it is often necessary to indicate not only how the cable or wire passes, but also its characteristics or method of laying. All this is also displayed graphically. This is also necessary information to read the drawings.
How are switches, switches, sockets depicted
Certain types of this equipment do not have images approved by the standards. So, dimmers (dimmers) and push-button switches remained without designation.
But all other types of switches have their own symbols in the electrical circuits. They are open and hidden installation, respectively, there are also two groups of icons. The difference is the position of the line on the image of the key. In order to understand on the diagram what type of switch in question, this must be remembered.
There are separate designations for 2-gang and 3-gang switches. In the documentation, they are called "double" and "triple", respectively. There are differences for enclosures with different degrees of protection. In rooms with normal operating conditions, they install switches with IP20, maybe up to IP23. In wet rooms(bathroom, swimming pool) or outdoors, the degree of protection must be at least IP44. Their images differ in that the circles are filled. So it's easy to tell them apart.
There are separate images for the switches. These are switches that allow you to control the on / off of light from two points (there are also three, but without standard images).
In the designation of sockets and outlet groups, the same tendency is observed: there are single, double sockets, there are groups of several pieces. Products for rooms with normal operating conditions (IP 20 to 23) have an unpainted center, for wet rooms with a high-protection enclosure (IP44 and higher), the center is tinted with a dark color.
Symbols in electrical circuits: sockets of different types of installation (open, hidden)
Having understood the logic of the notation and remembering some initial data (what is the difference conventional image sockets of open and hidden installation, for example), after a while you will confidently be able to navigate in the drawings and diagrams.
Lamps on the diagrams
This section describes the conventions in the electrical diagrams of various lamps and luminaires. Here the situation with the designations of the new element base is better: there are even signs for LED lamps and lamps, compact fluorescent lamps(housekeepers). It is also good that the images of lamps of different types differ significantly - it is difficult to confuse them. For example, lamps with incandescent lamps are depicted in the form of a circle, with long linear fluorescent lamps - in a long narrow rectangle. The difference in the image of a linear lamp of a fluorescent type and an LED one is not very big - only dashes at the ends - but even here you can remember.
The standard even contains symbols in electrical diagrams for a ceiling and pendant lamp (holder). They also have a rather unusual shape - small-diameter circles with dashes. In general, this section is easier to navigate than others.
Elements of basic electrical circuits
The schematic diagrams of the devices contain a different element base. Communication lines, terminals, connectors, light bulbs are also depicted, but, in addition, there are a large number of radioelements: resistors, capacitors, fuses, diodes, thyristors, LEDs. Most of the symbols in the electrical circuits of this element base are shown in the figures below.
More rare ones will have to be looked for separately. But most circuits contain these elements.
Letter symbols in electrical circuits
In addition to graphic images, elements on the diagrams are signed. It also helps to read the diagrams. Next to the letter designation of an element, there is often its serial number. This is done so that later it would be easy to find the type and parameters in the specification.
The table above shows international designations. There is also a domestic standard - GOST 7624-55. Excerpts from there with the table below.
An electrical diagram is a type of technical drawing that indicates various electrical elements in the form of symbols. Each element has its own designation.
All conventional (conventional-graphic) symbols on electrical circuits consist of simple geometric shapes and lines. These are circles, squares, rectangles, triangles, simple lines, dotted lines, etc. The designation of each electrical element consists of a graphic part and an alphanumeric part.
Thanks to the huge variety of electrical components, it becomes possible to create highly detailed electrical diagrams that are understandable to almost every electrician.
Each element in the electrical diagram must be carried out in accordance with GOST. Those. in addition to the correct display of the graphic image on the electrical circuit, all standard dimensions of each element, line thickness, etc. must be observed.
There are several basic types of electrical circuits. This is a single-line, schematic, wiring diagram (connection diagram). There are also schemes general view- structural, functional. Each species has its own purpose. The same item on different schemes can be denoted in the same way or in different ways.
The main purpose of a single-line diagram is a graphical display of the power supply system (power supply to the facility, electrical wiring in the apartment, etc.). Simply put, a single-line diagram depicts the power section of an electrical installation. By the name, you can understand that the single-line diagram is executed in the form of a single line. Those. electrical power supply (both single-phase and three-phase) supplied to each consumer is indicated by a single line.
To indicate the number of phases, special serifs are used on the graphic line. One notch indicates that the power supply is single-phase, three notches indicate that the power is three-phase.
In addition to the single line, the designations of protective and switching devices are used. The first devices include high-voltage switches (oil, air, SF6, vacuum), circuit breakers, residual current devices, differential circuit breakers, fuses, load break switches. The second includes disconnectors, contactors, magnetic starters.
High voltage circuit breakers in single line diagrams are depicted as small squares. As for automatic switches, RCDs, differential circuit breakers, contactors, starters and other protective and switching equipment, they are depicted in the form of a contact and some explanatory graphic additions, depending on the device.
The wiring diagram (connection diagram, connection, location) is used for the direct production of electrical work. Those. these are working drawings, using which the installation and connection of electrical equipment is carried out. Also, according to the wiring diagrams, separate electrical devices(electrical cabinets, electrical panels, control panels, etc.).
The wiring diagrams depict all wiring connections both between individual devices (circuit breakers, starters, etc.), and between different types of electrical equipment (electrical cabinets, shields, etc.). For correct connection wired connections on wiring diagram depicts electrical terminal blocks, terminals of electrical devices, brand and section electrical cables, numbering and lettering of individual wires.
Electrical schematic diagram - the most complete diagram with all electrical elements, connections, letter designations, technical characteristics of apparatus and equipment. According to the schematic diagram, other electrical circuits are performed (installation, single-line, equipment layout, etc.). The schematic diagram shows both the control circuits and the power section.
Control circuits (operational circuits) are buttons, fuses, starter or contactor coils, contacts of intermediate and other relays, contacts of starters and contactors, phase (voltage) control relays, as well as connections between these and other elements.
The power section depicts circuit breakers, power contacts of starters and contactors, electric motors, etc.
In addition to the graphic image itself, each element of the circuit is supplied with an alphanumeric designation. For example, a circuit breaker in a power circuit is designated QF. If there are several machines, each is assigned its own number: QF1, QF2, QF3 etc. The coil (winding) of the starter and contactor is designated KM. If there are several of them, the numbering is similar to the numbering of the machines: KM1, KM2, KM3 etc.
In each circuit diagram, if there is any relay, then at least one blocking contact of this relay is necessarily used. If the circuit contains an intermediate relay KL1, two contacts of which are used in the operational circuits, then each contact receives its own number. The number always starts with the number of the relay itself, and then comes the serial number of the contact. In this case, it turns out KL1.1 and KL1.2. The designations of auxiliary contacts of other relays, starters, contactors, automatic machines, etc. are carried out in the same way.
In electrical schematic diagrams, in addition to electrical elements, electronic designations are very often used. These are resistors, capacitors, diodes, LEDs, transistors, thyristors and other elements. Each electronic element the diagram also has its own letter and number designation. For example, a resistor is R (R1, R2, R3 ...). Capacitor - C (C1, C2, C3 ...) and so on for each element.
In addition to graphic and alphanumeric designations, technical characteristics are indicated on some electrical elements. For example, for a circuit breaker, this is the rated current in amperes, the cut-off trip current is also in amperes. For an electric motor, the power is indicated in kilowatts.
For the correct and correct drawing up of electrical circuits of any kind, it is necessary to know the designations of the elements used, state standards, and the rules for drawing up documentation.
When carrying out electrical work, each person, one way or another, is faced with the symbols that are in any electrical circuit. These diagrams are very diverse, with different functions, however, all graphic conventions are reduced to the same form and in all diagrams correspond to the same elements.
The main symbols in the electrical circuits of GOST are shown in the tables
Currently, not only domestic elements are used in electrical engineering and radio electronics, but also products manufactured by foreign firms. Imported electrical radioelements make up a huge assortment. They, without fail, are displayed in all drawings in the form of symbols. They determine not only the values of the main electrical parameters, but also a complete list of them included in a particular device, as well as the relationship between them.
To read and understand the contents of the wiring diagram
It is necessary to study well all the elements that make up its composition and the principle of operation of the device as a whole. Usually, all information is found either in reference books or in the specification attached to the schema. Positional designations characterize the relationship of the elements included in the device kit, with their designations on the diagram. In order to graphically designate one or another electrical radio element, standard geometric symbols are used, where each product is depicted separately, or in combination with others. The meaning of each individual image largely depends on the combination of symbols with each other.
Each diagram displays
Connections between separate elements and guides. In such cases, the standard designation of the same components and elements is of no small importance. For this, there are reference designations, where the types of elements, their design features and numerical values are displayed in literal expression. Elements used in a general manner are indicated in the drawings as qualifying, characterizing current and voltage, regulation methods, types of connections, pulse shapes, electronic communication other.
Reading electrical diagrams is a necessary skill to represent the operation of electrical networks, nodes, as well as various equipment. Not a single specialist will begin to install the equipment until he or she reads the accompanying regulatory documents.
Schematic electrical diagrams allow the developer to convey a complete report on the product in a condensed form to the user, using conventionally graphic symbols (UGO). To avoid confusion and defects when assembling according to drawings, alphanumeric designations are entered into a unified system for design documentation (ESKD). All schematic diagrams are developed and applied in full accordance with GOSTs (21.614, 2.722-68, 2.763-68, 2.729-68, 2.755-87). The GOST describes the elements, provides a decoding of the values.
Reading drawings
The schematic diagram shows all the elements, parts and networks that make up the drawing, electrical and mechanical connections. Reveals the full functionality of the system. All elements of any electrical circuit correspond to the designations positioned in GOST.
A list of documents is attached to the drawing, in which all the elements and their parameters are prescribed. Components are specified in alphabetical order, subject to digital sorting. The list of documents (specification) is indicated on the drawing itself, or made out in separate sheets.
How to study drawings
First, the type of drawing is determined. According to GOST 2.702-75, each graphic document the individual code corresponds. All electrical drawings have the letter designation "E" and the corresponding numerical value from 0 to 7. The electrical circuit diagram corresponds to the code "E3".
Reading the circuit diagram:
- Visually familiarize himself with the presented drawing, pay attention to the indicated notes and technical requirements.
- Find on schematic illustration all the components indicated in the list of the document;
- Determine the power source of the system and the type of current (single-phase, three-phase);
- Find the main nodes, and determine their power supply;
- Get acquainted with the elements and protection devices;
- To study the control method indicated on the document, its tasks and the algorithm of actions. Understand the sequence of actions of the device when starting, stopping, short circuit;
- Analyze the work of each section of the chain, determine the main components, auxiliary elements, study the technical documentation of the listed parts;
- Based on the studied data of the document, draw a conclusion about the processes occurring in each link of the chain shown in the drawing.
Knowing the sequence of actions, alphanumeric designations, you can read any electrical diagram.
Graphic symbols
The schematic diagram has two types - single-line and complete. On a single-line, only a power wire with all elements is drawn, if the main network does not differ in individual additions from the standard one. Two or three slashes applied to the wire line denote a single-phase or three-phase network, respectively. The entire network is drawn in full and the generally accepted symbols in the electrical circuits are put down.
Single line electric circuit diagram, single-phase network
Types and meaning of lines
- Thin and thick solid lines - in the drawings depicts lines of electrical, group communication, lines on the elements of the UGO.
- Dashed line - indicates the shielding of the wire or devices; denotes a mechanical link (motor-gearbox).
- Thin dash-dotted line - designed to highlight groups of several components that make up parts of the device, or a control system.
- A dash-dotted line with two dots is a disconnecting line. Shows a sweep important elements... Indicates an object remote from the device, connected to the system by mechanical or electrical communication.
Network trunks are shown in full, but according to the standards, they are allowed to be cut if they interfere with the normal understanding of the circuit. The break is indicated by arrows, next to them indicate the main parameters and characteristics of electrical circuits.
The bold point on the lines indicates the connection, the soldering of the wires.
Electromechanical components
Schematic representation of electromechanical links and contacts
A - UGO coil of an electromechanical element (magnetic starter, relay)
B - thermal relay
С - device coil with mechanical interlock
D - closing contacts (1), opening (2), switching (3)
E - button
F - designation of the switch (knife switch) on the electrical diagram of the UGO of some measuring instruments. Full list these elements are given in GOST 2.729 68 and 2.730 73.
Elements of electrical circuits, devices
| Number in the picture | Description | Number in the picture | Description |
|---|---|---|---|
| 1 | Electricity meter | 8 | Electrolytic capacitor |
| 2 | Ammeter | 9 | Diode |
| 3 | Voltmeter | 10 | Light-emitting diode |
| 4 | temperature sensor | 11 | Diode optocoupler |
| 5 | Resistor | 12 | Npn transistor picture |
| 6 | Rheostat (variable resistor) | 13 | Fuse |
| 7 | Capacitor |
UGO time relays, buttons, switches, limit switches are often used in the development of electric drive circuits.
Schematic representation of a fuse. When reading the electrical diagram, you should carefully consider all the lines and parameters of the drawing so as not to confuse the purpose of the element. For example, the fuse and resistor are slightly different. In the diagrams, the power line is shown passing through the fuse, the resistor is drawn without internal elements.
Full diagram of a circuit breaker
Contact switching device. Serves automatic protection electrical network from accidents, short circuits. It can be powered mechanically or electrically.
Single line circuit breaker
The transformer is steel core with two windings. There is one and three-phase, step-up and step-down. It is also subdivided into dry and oil, depending on the cooling method. Power ranges from 0.1 MVA to 630 MVA (in Russia).
UGO transformers
Designation of current transformers in the full (a) and single-line (c) diagrams
Graphic designation of electrical machines (EM)
Electric motors, depending on the type, are capable of not only consuming energy. When developing industrial systems, use motors that generate energy into the network when there is no load, thereby reducing costs.
A - Three-phase electric motors:
1 - Asynchronous with a squirrel-cage rotor
2 - Asynchronous with squirrel-cage rotor, two-speed
3 - Asynchronous with a phase rotor
4 - Synchronous electric motors; generators.
B - DC collector motors:
1 - with excitation of the winding from a permanent magnet
2 - Electric machine with an excitation coil
In conjunction with electric motors, the diagrams show magnetic starters, soft starters, and a frequency converter. These devices are used to start electric motors, the smooth operation of the system. The last two elements protect the network from voltage “sag” in the network.
UGO magnetic starter on the diagram
Switches function as switching equipment. Disconnect and include in the work of certain sections of the network, as needed.
Graphical symbols in electrical diagrams of mechanical switches
Conditional graphic designations of sockets and switches in electrical circuits. Include in the developed drawings of electrification of houses, apartments, industries.
A bell on the electrical diagram according to UGO standards with a designated size
Dimensions of UGO in electrical circuits
On the diagrams, the parameters of the elements included in the drawing are applied. Full information about the element, capacitance, if it is a capacitor, rated voltage, resistance for the resistor are registered. This is done for convenience, so as not to make a mistake during installation, not to waste time on calculating and selecting the components of the device.
Sometimes the nominal data is not indicated, in this case the parameters of the element do not matter, you can select and install a link with a minimum value.
The accepted dimensions of the UGO are prescribed in the GOST standards of the ESKD standard.
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Dimensions in ESKD
The dimensions of graphic and letter images in the drawing, the thickness of the lines should not differ, but it is permissible to change them proportionally in the drawing. If in the symbols on various electrical circuits of GOST, there are elements that do not have information about the sizes, then these components are performed in sizes corresponding to the standard image of the UGO of the entire circuit.
UGO of the elements that make up the main product (device) can be drawn in a smaller size in comparison with other elements.
Along with UGO for more precise definition the names and purposes of the elements, the letter designation is applied to the diagrams. This designation is used for links in text documents and for drawing on an object. Using the letter designation, the name of the element is determined, if this is not clear from the drawing, technical parameters, quantity.
Additionally, one or more numbers are indicated with a letter designation, usually they explain the parameters. An additional letter code indicating the denomination, model, additional data is written in the accompanying documents, or is placed in a table in the drawing.
To learn how to read electrical circuits, it is not necessary to know all the letter designations by heart, graphic images various elements, it is enough to navigate in the corresponding GOST ESKD. The standard includes 64 GOST documents that disclose the main provisions, rules, requirements and designations.
The main symbols used in the diagrams according to the ESKD standard are shown in Tables 1 and 2.
Table 1
|
First letter of code (required) |
Element view group | Examples of element types |
| A | Devices | Amplifiers, telecontrol devices, lasers, masers |
| B | Loudspeakers, microphones, thermoelectric sensors, ionizing radiation detectors, pickups, selsyns | |
| C | Capacitors | |
| D | Integrated analog digital circuits, logic elements, memory devices, delay devices | |
| E | The elements are different | Lighting devices, heating devices |
| F | Discrete current and voltage protection elements, fuses, arresters | |
| G | Generators, power supplies, quartz oscillators | Batteries, accumulators, electrochemical and electrothermal sources |
| H | Indicating and signaling devices | Sound and light alarm devices, indicators |
| K | Relays, contactors, starters | Current and voltage relays, electric thermal relays, time relays, contactors, magnetic starters |
| L | Fluorescent light chokes | |
| M | Engines | DC and AC motors |
| P | Indicating, recording and measuring devices, counters, clocks | |
| Q | Disconnectors, short-circuits, circuit breakers (power) | |
| R | Resistors | Variable resistors, potentiometers, varistors, thermistors |
| S | Switching devices in control, signaling and measuring circuits | Switches, switches, switches, triggered by various influences |
| T | Current and voltage transformers, stabilizers | |
| U | Converters of electrical quantities to electrical, communication devices | Modulators, demodulators, discriminators, inverters, frequency converters, rectifiers |
| V | Electronic tubes, diodes, transistors, thyristors, zener diodes | |
| W | Microwave lines and elements, antennas | Waveguides, dipoles, antennas |
| X | Contact connections | Pins, sockets, dismountable joints, collectors |
| Y | Electromagnetic clutches, brakes, chucks | |
| Z | Terminal devices, filters, limiters | Modeling lines, quartz filters |
The main two-letter designations are shown in Table 2
| First letter of code (required) | Element view group | Examples of element types | Two-letter code |
| A | Device (general designation) | ||
| B | Converters of non-electrical quantities to electrical quantities (excluding generators and power supplies) or vice versa analog or multi-digit converters or sensors for indicating or measuring | Speaker | BA |
| Magnetostrictive element | BB | ||
| Detector of ionizing elements | BD | ||
| Selsin - receiver | BE | ||
| Telephone (capsule) | Bf | ||
| Selsin - sensor | BC | ||
| Thermal sensor | BK | ||
| Photocell | BL | ||
| Microphone | BM | ||
| Pressure meter | BP | ||
| Piezoelectric element | BQ | ||
| RPM sensor (tachogenerator) | BR | ||
| Pickup | BS | ||
| Speed sensor | BV | ||
| C | Capacitors | ||
| D | Integrated circuits, microassemblies | Analog integrated circuit | DA |
| Integrated circuit, digital, logic element | DD | ||
| Information storage device | DS | ||
| Delay device | DT | ||
| E | The elements are different | A heating element | EK |
| Lighting lamp | EL | ||
| Igniter | ET | ||
| F | Arresters, fuses, protective devices | Discrete instantaneous current protection element | FA |
| Discrete inertial current protection element | FP | ||
| Fuse fuse | FU | ||
| Discrete voltage protection element, arrester | FV | ||
| G | Generators, power supplies | Battery | GB |
| H | Indicator and signal elements | Sound alarm device | HA |
| Character indicator | HG | ||
| Light signaling device | HL | ||
| K | Relays, contactors, starters |
Relay current | KA |
| Indicator relay | KH | ||
| Electric thermal relay | KK | ||
| Contactor, magnetic starter | KM | ||
| Time relay | KT | ||
| Voltage relay | KV | ||
| L | Inductors, chokes | Fluorescent light choke | LL |
| M | Engines | - | - |
| P | Instruments, measuring equipment | Ammeter | PA |
| Pulse counter | PC | ||
| Frequency meter | PF | ||
| Note. The combination of PE is not allowed | Active energy meter | PI | |
| Reactive energy meter | PK | ||
| Ohmmeter | PR | ||
| Recording device | PS | ||
| Clock, action time meter | PT | ||
| Voltmeter | PV | ||
| Wattmeter | PW | ||
| Q | Switches and disconnectors in power circuits | Automatic switch | QF |
| Short-circuiter | QK | ||
| Disconnector | QS | ||
| R | Resistors | Thermistor | RK |
| Potentiometer | RP | ||
| Measuring shunt | Rs | ||
| Varistor | RU | ||
| S | Switching devices in control, signaling and measuring circuits. Note. The designation SF is used for devices without power circuit contacts. |
Switch or switch | SA |
| Push-button switch | SB | ||
| Automatic switch | SF | ||
| Switches triggered by various influences: - from the level |
SL | ||
| - from pressure | SP | ||
| - from position (track) | SQ | ||
| - from the frequency of rotation | SR | ||
| - from temperature | SK | ||
| T | Transformers, autotransformers | Current transformer | TA |
| Electromagnetic stabilizer | TS | ||
| Voltage transformer | TV | ||
| U | Communication devices. Converters of electrical quantities to electrical |
Modulator | UB |
| Demodulator | UR | ||
| Discriminator | UI | ||
| Frequency converter, inverter, frequency generator, rectifier | UZ | ||
| V | Electrovacuum and semiconductor devices | Diode, Zener diode | VD |
| Electrovacuum device | VL | ||
| Transistor | VT | ||
| Thyristor | VS | ||
| W | Microwave lines and elements Antennas | Coupler | WE |
| Short-circuiter | Wk | ||
| Valve | Ws | ||
| Transformer, discontinuity, phase shifter | WT | ||
| Attenuator | WU | ||
| Antenna | WA | ||
| X | Contact connections | Current collector, sliding contact | XA |
| Pin | XP | ||
| Nest | XS | ||
| Collapsible connection | XT | ||
| High frequency connector | XW | ||
| Y | Mechanical devices with electromagnetic drive | Electromagnet | Ya |
| Electromagnetic brake | YB | ||
| Electromagnetic clutch | YC | ||
| Electromagnetic chuck or plate | YH | ||
| Z | Terminal devices Filters. Limiters | Limiter | ZL |
| Quartz filter | ZQ |
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