Designation of elements on a printed circuit board. Symbols in various electrical circuits. Basic requirements for drawings

Positional designations

These are special alphabetic indices of elements, their groups, blocks, devices, identifying them on the diagram. To unambiguously point to specific element these designations are made unique within the schema.

In most cases, these indices have the form, like: R1, DA7, HL5, where the letter (letters) denote the category of the denoted (R - resistor, DA - analog microcircuit, etc.), and the numbers - the number in the circuit in order (for example, R1 , R2, R3 ... are resistors in the diagram).

Hierarchical designations are also widely used, consisting of several groups of letters and numbers, sometimes separated by other characters:

DD2.1 - digital microcircuit number 2, element 1 (according to GOST);
A2C7 - block (for example, a board) number 2, capacitor 7 (also according to GOST);
U2A - microcircuit 2, element A (predominantly American designations).

Positional designations within the framework are regulated by GOST 2.710-81 pdf

In short, the reference designation in the ESKD consists of the following parts:

Device designation (type = NANA);
functional group designations (like #NANA);
constructive designation (type + NANA), the above elements are separated from the following by a dash (-);
the type and number of the element (type AN; A - type, N - number);
functions (type A);
contact designations (type: NANA);
address designation (in brackets).

Of which only the type and number of the element are mandatory.

As designations for the types of elements, letters or sequences of letters are used, in which the first (or only) letter is the class of the device, and the rest specify the functional or constructive group. Clarifying letters can be omitted (for example, digital microcircuits can be designated as Dn, instead of DAn).

A Device (general designation)
AA Current Regulator
AK relay box
B Converters of non-electrical quantities to electrical (eg generators and power supplies) or vice versa, analog or multi-digit converters and sensors for indicating and measuring
BA Loudspeaker
BB Magnetostrictive element
BD Ionizing radiation detector
BE Selsin Receiver
BF Telephone (capsule)
BC Selsyn Sensor
BK Thermal sensor
BL Photocell
BM Microphone
BP Pressure sensor
BQ Piezoelectric
BR Speed ​​sensor (tachogenerator)
BS Pickup
BV Speed ​​sensor
C Capacitors
CB Power capacitor bank
CG Capacitor bank
D Integrated circuits, microassemblies
DA Analog integrated circuit
DD Digital integrated circuit
DS Storage Devices
DT Delay device
E Items are different
EK Heating element
EL Lighting lamp
ET Igniter
F Arresters, fuses, protective devices
FA Discrete instantaneous current protection element
FP Discrete inertial current protection element
FU Fuse fuse
FV Discrete voltage protection element, arrester
G Generators, power supplies
GB Battery
GC Synchronous compensator
GE Exciter Generator
H Indicating and signaling devices
HA Appliance sound signal izatsii
HG Character indicator
HL Light signaling indicator
HLA Signal board
HLG Signal lamp green
HLR Signal lamp red
HLW White signal lamp
HV Ionic and semiconductor indicators
K Relays, contactors, starters
KA Current relay
KCC Close command relay
KCT Trip command relay
KH Indicator relay
KK Electric thermal relay
KL Relay, intermediate
KM Contactor, magnetic starter
KT Time relay
KV Voltage relay
L Inductors, chokes
LL Choke for electroluminescent lighting
LM Motor field winding
M Engines
MA Electric motors
P Instruments, measuring equipment
PA Ammeter
PC Pulse counter
PE Not allowed
PF Frequency Counter
PI Active energy meter
PK Reactive energy meter
PR Ohmmeter
PS Recorder
PT Clock, action time meter
PV Voltmeter
PW Wattmeter
Q Switches and disconnectors in power circuits
QF Automatic circuit breaker
QK Short-circuiter
QS Disconnector
R Resistors
RK Thermistor
RP Potentiometer
RR Rheostat
RS Measuring shunt
RU Varistor
S Switching devices in control, signaling and measuring circuits
SA Switch or switch
SB Push button switch
SF Push-button switch (for devices without power circuit contacts)
SL Level tripped switch
SP - from pressure
SQ - from position (track)
SR - from the speed
SK - from temperature
T Transformers, autotransformers
TA Current transformer
TS Electromagnetic stabilizer
TV Voltage transformer
U Communication devices, converters of electrical quantities into electrical
UB Modulator
UF Frequency converter
UG Power supply
UI Discriminator
UR Demodulator
UZ Frequency converter, inverter, frequency generator, rectifier
V Electrovacuum and semiconductor devices
VD Diode, Zener diode
VL Electrovacuum device
VT Transistor
VS Thyristor
W Microwave lines and elements, antennas
WA Antenna
WE Coupler
WK Short-circuiter
WS Valve
WT Transformer, discontinuity, phase shifter
WU Attenuator
X Pin connections
XA Collector trolley, sliding contact
XP Pin
XS Socket
XT Dismountable connection
XW High frequency connector
Y Mechanical devices with electromagnetic drive
YA Electromagnet
YAB Electromagnetic lock
YB Electromagnetic brake
YC Electromagnetic Clutch
YH Electromagnet chuck or plate
Z Terminals, limiters, filters
ZL Limiter
ZQ Quartz filter

Foreign designations (Reference designators)

Unlike domestic ones, foreign designations have many letter designations of types differ.

Here is a list of common foreign designations.

AE Antenna
AT Attenuator
BR Bridge Rectifier
B, BT Battery
C Capacitor
CN Capacitor assembly
CRT Picture tube
D, CR Diode (Including Zener diodes, thyristors and LEDs)
DL Delay Line
DS Display
DSP Digital Signal Processor
F Fuse
FB or FEB Ferrite bead (for RFI filtering)
FD Fiducial
FET Field Effect Transistor
GDT Gas Discharge Lamp
IC Chip (also U)
J Socket
J, JP Jumper (jumper)
JFET Single Junction Field Effect Transistor
K Relay
L Inductance
LCD LCD
LDR Photoresistor
LED LED
LS Loudspeaker, sound emitters (tweeters)
M Electric motor
MCB Breaker
MK, Mic Microphone
MOSFET MOSFET
MP Mechanical parts (fasteners, etc.)
Ne Neon lamp
OP Operational Amplifier
P Plug
PCB Printed circuit board
PS Power supply
PU Pickup
Q Transistor (all kinds, also Tr)
R Resistor
RLA, RY Relay (also K)
RN Resistor network
RT Thermistor (also TH)
RV Varistor
S Switching devices
SCR Thyristor
SW Switch
T Transformer
TC Thermocouple
TUN Tuner
TFT TFT display
TH Thermistor (also RT)
TP Test point
Tr Transistor (all kinds, also Q)
U Microcircuit (also IC)
V Radio tube
VC Variable capacitor
VFD Gas Discharge Display
VLSI very large scale integration
VR Variable resistor
X Converters not elsewhere classified
X Quartz, ceramic resonator (also Y)
XMER Transformer
XTAL Crystal Resonator
Y Quartz, ceramic resonator (also X)
Z, ZD Zener diode

Historical

Before the introduction of GOST in the USSR, notation using the Cyrillic alphabet was also used (with the exception of R, C, L).

A antenna
B galvanic cell, accumulator, battery
Vk switch
Generator
Gr loudspeaker
D semiconductor diode
Dr throttle
Sound pickup
L radio tube
M microphone
Nl neon lamp
Switch
R relay
T transistor
Tl head phone
Tr transformer
TC thermistor
PV photocell
R resistor
C capacitor
L inductance

- electronic components assembled into analog and digital devices: televisions, measuring instruments, smartphones, computers, laptops, tablets. If earlier the details were depicted close to their natural appearance, today the conventional graphic designations of radio components on the diagram, developed and approved by the International Electrotechnical Commission, are used.

Types of electronic circuits

In electronics, several types of circuits are distinguished: schematic, wiring, block diagrams, voltage and resistance maps.

Schematic diagrams

Such a wiring diagram gives a complete picture of all the functional nodes of the circuit, the types of connections between them, the principle of operation of electrical equipment. Schematic diagrams are commonly used in distribution networks... They are divided into two types:

• Single line. In such a drawing, only power circuits are depicted.
• Full. If the electrical installation is simple, then all its elements can be displayed on one sheet. To describe the equipment, which includes how many circuits (power, measuring, control), drawings are made for each node and placed on different sheets.

Block diagrams

An independent part of an electronic device is called a block in electronics. A block is a general concept; it can include both a small and a significant number of parts. The block diagram (or block diagram) gives only a general idea of ​​the structure of an electronic device. It does not display: the exact composition of the blocks, the number of ranges of their functioning, the schemes by which they are assembled. On the block diagram, blocks are indicated by squares or circles, and the connections between them are indicated by one or two lines. Signal directions are indicated by arrows. Block names in full or abbreviated form can be applied directly to the diagram. The second option is block numbering and decoding of these numbers in the table located in the margins of the drawing. On the graphic images of the blocks, the main details can be displayed or graphs of their work can be applied.

Mounting

Wiring diagrams are convenient for self-drawing up an electrical circuit. They indicate the location of each element of the circuit, communication methods, laying of connecting wires. The designation of radioelements in such diagrams usually approaches their natural appearance.

Voltage and resistance maps

A stress map (diagram) is a drawing, in which, next to individual parts and their terminals, the values ​​of stresses characteristic of normal work device. The voltages are set in the gaps of the arrows showing where the measurements are to be made. On the resistance map, resistance values ​​are indicated that are characteristic of a working device and circuits.

How are the various radio components indicated on the diagrams

As it was said earlier, there is a certain graphic symbol to designate radio components of each type.

Resistors

These parts are designed to regulate the current in the circuit. Fixed resistors have a certain and constant resistance value. For variables, the resistance is in the range from zero to the specified maximum value. The names and symbols of these radio components on the diagram are regulated by GOST 2.728-74 ESKD. In the general case, in the drawing, they represent a rectangle with two leads. American manufacturers designate resistors in the circuits with a zigzag line. the image of resistors on the diagrams
the image of resistors on schematic diagrams

Fixed resistors

They are characterized by resistance and power. They are indicated by a rectangle with lines indicating a specific power value. Exceeding the specified value will lead to the failure of the part. The diagram also indicates: the letter R (resistor), a number indicating the serial number of the part in the circuit, the value of resistance. These radio parts are designated by numbers and letters - "K" and "M". The letter "K" means kOhm, "M" - mOhm.

Variable resistors

the image of variable resistors on the diagrams Their design includes a movable contact, which changes the resistance value. The part is used as a regulating element in audio and other similar techniques. On the diagram, it is indicated by a rectangle indicating fixed and movable contacts. The drawing shows a constant nominal resistance. There are several options for connecting resistors:
resistor connection options

• Consistent. The end pin of one part is connected to the start pin of the other. A common current flows through all elements of the circuit. Connecting each subsequent resistor increases the resistance.
• Parallel. The initial conclusions of all resistances are connected at one point, the final ones - at another. Current flows through each resistor. The total resistance in such a circuit is always less than the resistance of an individual resistor.
• Mixed. This is the most popular type of connection of parts, combining the two described above.

Capacitors

graphic representation of capacitors on the diagrams A capacitor is a radio component consisting of two plates separated by a dielectric layer. It is applied to the circuit in the form of two lines (or rectangles - for electrolytic capacitors), denoting the plates. The gap between them is a dielectric layer. Capacitors are second only to resistors in terms of popularity in circuits. Capable of accumulating electric charge with the subsequent return.

• Fixed capacitors. The letter "C" is placed near the icon, the serial number of the part, the value of the nominal capacity.
• With variable capacity. The values ​​of the minimum and maximum capacity are stamped next to the graphic icon.

In circuits with high voltage in capacitors, with the exception of electrolytic ones, the voltage value is indicated after the capacitance. When connecting electrolytic capacitors, polarity must be observed. To denote a positively charged plate, use the "+" sign or a narrow rectangle. If there is no polarity, both plates are indicated by narrow rectangles. Electrolytic capacitors are installed in the power supply filters of low-frequency and impulse devices.

Diodes and Zener Diodes

graphic representation of diodes and zener diodes on circuits A diode is a semiconductor device designed to pass an electric current in one direction and create obstacles to its flow in the opposite direction. This radioelement is designated in the form of a triangle (anode), the top of which is directed towards the current flow. A line (cathode) is placed in front of the apex of the triangle. Zener diode is a kind of semiconductor diode. Stabilizes reverse polarity voltage applied to the terminals. A stabilizer is a diode, to the terminals of which a voltage of direct polarity is applied.

Transistors

Transistors are semiconductor devices used to generate, amplify, and convert electrical oscillations. With their help, they control and regulate the voltage in the circuit. They differ in a variety of designs, frequency ranges, shapes and sizes. The most popular are bipolar transistors, denoted by the letters VT in the diagrams. They are characterized by the same electrical conductivity of the collector and emitter.
graphic representation of transistors on the diagrams

Microcircuits

Microcircuits are electronic components that are complex in composition. They are a semiconductor substrate in which resistors, capacitors, diodes and other radio components are integrated. They are used to convert electrical impulses into digital, analog, analog-digital signals. Manufactured with or without housing. The rules for the conventional graphic designation (UGO) of digital and microprocessor microcircuits are regulated by GOST 2.743-91 ESKD. According to them, the UGO has the shape of a rectangle. The diagram shows the supply lines to it. The rectangle consists only of the main field or the main field and two additional ones. In the main field, it is mandatory to indicate the functions performed by the element. The additional fields usually decipher the pin assignments. The main and additional fields may or may not be separated by a solid line. graphic representation of microcircuits

Buttons, relays, switches

graphic representation of buttons and switches on the diagram

the image of the relay on the diagrams

Letter designation of radio components in the diagram

Letter codes of radioelements on schematic diagrams

Devices and elements	Letter code
Devices: amplifiers, telecontrol devices, lasers, masers; general designation	A
Converters of non-electrical quantities to electrical (except for generators and power supplies) or vice versa, analog or multi-digit converters, sensors for indicating or measuring; general designation	V
Speaker	VA
Magnetostrictive element	BB
Ionizing radiation detector	BD
Selsin sensor	Sun
Selsin-receiver	BE
Telephone (capsule)	Bf
Thermal sensor	VC
Photocell	BL
Microphone	VM
Pressure sensor	BP
Piezoelectric element	IN
RPM sensor, tachogenerator	BR
Pickup	BS
Speed ​​sensor	BѴ
Capacitors	WITH
Integrated microcircuits, microassemblies: general designation	D
Integrated analog microcircuit	DA
Integrated digital microcircuit, logic element	DD
Information storage device (memory)	DS
Delay device	DT
Elements are different: general designation	E
Lighting lamp	EL
A heating element	EC
Arresters, fuses, protection devices: general designation	F
Fuse fuse	FU
Generators, power supplies, quartz generators: general designation	G
Battery of galvanic cells, accumulators	GB
Indicating and signaling devices; general designation	H
Sound alarm device	ON
Character indicator	HG
Light signaling device	HL
Relays, contactors, starters; general designation	TO
Electric thermal relayѳ	kk
Time relay	CT scan
Contactor, magnetic starter	km
Inductors, chokes; general designation	L
Motors, general designation	M
Measuring devices; general designation	R
Ammeter (milliammeter, microammeter)	RA
Pulse counter	PC
Frequency counter	PF
Ohmmeter	PR
Recording device	PS
Action time meter, clock	RT
Voltmeter	PV
Wattmeter	PW
Constant and variable resistors; general designation	R
Thermistor	RK
Measuring shunt	Rs
Varistor	RU
Switches, disconnectors, short-circuits in power circuits (in equipment power circuits); general designation	Q
Switching devices in control, signaling and measuring circuits; general designation	S
Switch or switch	SA
Push-button switch	SB
Automatic switch	SF
Transformers, autotransformers; general designation	T
Electromagnetic stabilizer	TS
Converters of electrical quantities into electrical, communication devices; general designation	and
Modulator	iv
Demodulator	UR
Discriminator	Ul
Frequency converter, inverter, frequency generator, rectifier	UZ
Semiconductor and vacuum devices; general designation	V
Diode, Zener diode	VD
Transistor	VT
Thyristor	VS
Electrovacuum device	VL
Microwave lines and elements; general designation	W
Coupler	WE
Koro tkoea we cat tel	Wk
Valve	WS
Transformer, phase shifter, discontinuity	WT
Attenuator	WU
Antenna	WA
Contact connections; general designation	X
Pin (plug)	XP
Socket (socket)	XS
Collapsible connection	XT
High frequency connector	XW
Mechanical devices with an electromagnetic drive; general designation	Y
Electromagnet	YA
Electromagnetic brake	YB
Electromagnetic clutch	YC
Terminal devices, filters; general designation	Z
Limiter	ZL
Quartz filter	ZQ

Letter codes for the functional purpose of a radio-electronic device or element

Functional purpose of the device, element	Letter code
Auxiliary	A
Counting	WITH
Differentiating	D
Protective	F
Test	G
Signal	H
Integrating	1
Hpavny	M
Measuring	N
Proportional	R
State (start, stop, limit)	Q
Return, reset	R
Memorizing, recording	S
Synchronizing, delaying	T
Speed ​​(acceleration, deceleration)	V
Summing	W
Multiplication	X
Analog	Y
Digital	Z

Letter abbreviations for electronics

Letter abbreviation	Explanation of abbreviation
AM	amplitude modulation
AFC	automatic frequency control
APCHG	automatic local oscillator frequency adjustment
APCHF	automatic frequency and phase adjustment
AGC	automatic gain control
ARYA	automatic brightness control
AS	acoustic system
AFU	antenna feeder
ADC	analog-to-digital converter
Frequency response	frequency response
BGIMS	large hybrid integrated circuit
NOS	wireless remote control
BIS	large integrated circuit
Biofeedback	signal processing unit
BP	power unit
BR	scanner
DBK	radio channel unit
BS	information block
BTK	blocking transformer personnel
BTS	blocking transformer lowercase
BOO	Control block
BC	color block
BCI	integrated chromaticity unit (using microcircuits)
VD	video detector
VIM	pulse time modulation
WU	video amplifier; input (output) device
HF	high frequency
G	heterodyne
GW	reproducing head
MHF	high frequency generator
MHF	hyperhigh frequency
GZ	start generator; recording head
GIR	heterodyne resonance indicator
GIS	hybrid integrated circuit
GKR	frame generator
GKCH	sweeping frequency generator
GMV	meter wave generator
GPA	smooth range generator
GO	envelope generator
HS	signal generator
GSR	line scan generator
gss	standard signal generator
yy	clock generator
GU	universal head
GUN	voltage controlled generator
D	detector
dv	long waves
dd	fractional detector
day	voltage divider
dm	power divider
dmv	decimeter waves
DU	remote control
DShPF	dynamic noise reduction filter
EASC	unified automated communication network
ESKD	unified system of design documentation
hr	sound frequency generator; master oscillator
ss	decelerating system; sound signal; pickup
ZCH	sound frequency
AND	integrator
iqm	pulse code modulation
IKU	quasi-peak level meter
ims	integrated circuit
ini	linear distortion meter
inch	infra-low frequency
and he	reference voltage source
sp	power supply
ichh	frequency response meter
To	switch
KBV	traveling wave ratio
Kv	short waves
kvh	extremely high frequency
kzv	recording-playback channel
Kim	pulse code modulation
kk	frame reel deflector
km	coding matrix
csch	extremely low frequency
efficiency	efficiency
KS	coil deflection line
csv	standing wave ratio
ksvn	voltage standing wave ratio
CT scan	check Point
CF	focusing coil
TWT	traveling wave lamp
lz	delay line
fishing	backward wave lamp
lpd	avalanche diode
lppt	tube semiconductor TV
m	modulator
MA	magnetic antenna
MB	meter waves
mdp	metal-dielectric-semiconductor structure
MNP	metal-oxide-semiconductor structure
ms	chip
MU	microphone amplifier
nor	nonlinear distortion
LF	low frequency
ABOUT	common base (switching on the transistor according to the scheme with a common base)
sheepskin	very high frequency
oi	common source (turning on the transistor * according to the scheme with a common source)
OK	common collector (switching on the transistor according to the scheme with a common collector)
onch	very low frequency
oos	negative feedback
OS	deflection system
OU	operational amplifier
OE	common emitter (switching on the transistor according to the scheme with a common emitter)
Surfactant	surface acoustic waves
pds	dual-voice prefix
Remote control	remote control
pkn	code-voltage converter
pnc	voltage-to-code converter
pnch	converter voltage frequency
pos	positive feedback
PPU	jamming device
pch	intermediate frequency; frequency converter
ptk	tv channel switch
pts	full tv signal
Vocational school	industrial television set
PU	preliminary effort
PUV	playback preamplifier
BLS	recording preamplifier
PF	band pass filter; piezofilter
nx	transfer characteristic
pcts	full color television signal
Radar	line linearity regulator; radar station
RP	memory register
RPCHG	manual adjustment of the local oscillator frequency
RRS	row size adjuster
PC	shift register; mixing regulator
RF	notch or block filter
CEA	electronic equipment
SBDU	wireless remote control system
VLSI	ultra-large-scale integrated circuit
SV	medium waves
swp	touch program selection
Microwave	ultra high frequency
cr	signal generator
SDV	extra-long waves
SDU	dynamic light installation; remote control system
SC	channel selector
SLE	all-wave channel selector
sk-d	decimeter wave channel selector
SK-M	meter wave channel selector
CM	mixer
ench	ultra-low frequency
Joint venture	mesh field signal
ss	sync signal
ssi	horizontal sync pulse
SU	selector amplifier
mid	average frequency
Tv	tropospheric radio waves; TV
tvs	output transformer line
tvz	audio output channel transformer
tvk	output transformer
Titus	TV test chart
TKE	temperature coefficient of capacitance
weaves	temperature coefficient of inductance
tkmmp	temperature coefficient of initial permeability
tcns	temperature coefficient of stabilization voltage
tks	temperature coefficient of resistance
mf	network transformer
mall	television center
ttsp	color stripe table
THAT	technical conditions
Have	amplifier
HC	playback amplifier
UVS	video amplifier
UVH	fetch-store
UHF	high frequency signal amplifier
UHF	UHF
UZ	recording amplifier
UZCH	audio amplifier
VHF	ultrashort waves
ULPT	unified semiconductor tube TV
ULCT	unified tube semiconductor color TV
ULT	unified tube TV
UMZCH	audio power amplifier
CNT	unified tv
ULF	low frequency amplifier
UNU	voltage controlled amplifier.
UTP	constant current amplifier; unified semiconductor TV
UCH	intermediate frequency amplifier
UPCHZ	intermediate frequency amplifier sound?
UPCHI	image intermediate frequency amplifier
URCH	radio frequency amplifier
US	interface device; comparison device
UHCH	microwave amplifier
OSS	horizontal sync amplifier
USU	universal touch device
Uu	control device (node)
UE	accelerating (control) electrode
UEIT	universal electronic test chart
PLL	phase locked loop
HPF	high pass filter
FD	phase detector; photodiode
FIM	phase-pulse modulation
FM	phase modulation
LPF	low pass filter
FPF	intermediate frequency filter
FPChZ	audio intermediate frequency filter
FPCI	image IF filter
FSI	lumped selectivity filter
FSS	concentrated selection filter
FT	phototransistor
PFC	phase-frequency response
DAC	digital-to-analog converter
Digital computer	digital computer
CMU	color music installation
CT	central television
BH	frequency detector
CHIM	pulse frequency modulation
chm	frequency modulation
shim	pulse width modulation
shs	noise signal
ev	electron volt (e V)
COMPUTER.	electronic computer
emf	electromotive force
eq	electronic switch
CRT	cathode-ray tube
AMY	electronic musical instrument
emos	electromechanical feedback
EMF	electromechanical filter
EPU	playing device
Electronic computer	electronic digital computer

Almost all UOS, all electronic and electrical products manufactured by industrial organizations and enterprises, home craftsmen, young technicians and radio amateurs, contain a certain amount of various purchased ERI and elements produced mainly by domestic industry. But for recent times there is a tendency to use ERE and foreign-made components. These include, first of all, PPP, capacitors, resistors, transformers, chokes, electrical connectors, batteries, HIT, switches, installation products and some other types of ERE.

Used purchased components or independently manufactured EREs will necessarily be reflected in the basic and installation electrical diagrams devices, in drawings and other TD, which are carried out in accordance with the requirements of ESKD standards.

Particular attention is paid to circuit diagrams, which determine not only the main electrical parameters, but also all the elements included in the device and the electrical connections between them. To understand and read the circuit diagrams, you must carefully familiarize yourself with the elements and accessories included in them, know exactly the scope and principle of operation of the device in question. As a rule, information about the ERE used is indicated in reference books and specifications - a list of these elements.

The connection of the list of ERE components with their conventional graphic designations is carried out through reference designations.

To construct conventional graphic symbols for ERE, standardized geometric symbols are used, each of which is used separately or in combination with others. In this case, the meaning of each geometric image in the conventional designation in many cases depends on the combination with which other geometric symbol it is used.

The standardized and most commonly used conventional graphic designations of ERE in electrical circuit diagrams are shown in Fig. 1. 1. These designations relate to all component elements of the circuits, including ERE, conductors and connections between them. And here the condition for the correct designation of the same type of ERE components and products is of paramount importance. For this purpose, reference designations are used, a mandatory part of which is the letter designation of the type of element, the type of its design and the digital designation of the ERE number. The diagrams also use the additional part of the designation of the ERE position, indicating the function of the element, in the form of a letter. The main types of letter designations of circuit elements are given in table. 1.1.

The designations in the drawings and diagrams of elements of general use refer to qualification ones that establish the type of current and voltage. type of connection, control methods, pulse shape, type of modulation, electrical connections, direction of transmission of current, signal, energy flow, etc.

Currently, the population and the trade network are in operation a significant number of various electronic devices and devices, radio and television equipment, which are manufactured by foreign firms and various joint-stock companies. In stores you can buy Various types ERI and ERE with foreign designations. Table 1. 2 provides information about the most common ERE of foreign countries with the appropriate designations and their analogues of domestic production.

This information is published for the first time in such a volume.

1- pnp structure transistor in a package, general designation;

2- transistor structures n-p-n in the case, general designation,

3 - field-effect transistor with p-n junction and n channel,

4 - field-effect transistor with p-n junction and p channel,

5 - unijunction transistor with base n type, b1, b2 - base terminals, e - emitter output,

6 - photodiode,

7 - rectifier diode,

8 - one-way zener diode (avalanche rectifier diode),

9 - heat-electric diode,

10 - diode dinistor, lockable in the opposite direction;

11 - zener diode (diode avalanche rectifier) ​​with double-sided conductivity,

12 - triode thyristor;

13 - photoresistor;

14 - variable resistor, rheostat, general designation,

15 - variable resistor,

16 - variable resistor with taps,

17 - trimmer resistor-potentiometer;

18 - thermistor with a positive temperature coefficient of direct heating (heating),

19 - varistor;

20 - constant capacitor, general designation;

21 - polarized fixed capacitor;

22 - polarized electrolytic oxide capacitor, general designation;

23 - constant resistor, general designation;

24 - constant resistor with a rated power of 0.05 W;

25 - constant resistor with a rated power of 0, 125 W,

26 - constant resistor with a rated power of 0.25 W,

27 - constant resistor with a rated power of 0.5 W,

28 - constant resistor with a rated power of 1 W,

29 - constant resistor with a rated power dissipation of 2 W,

30 - constant resistor with a rated power dissipation of 5 W;

31 - constant resistor with one symmetrical additional tap;

32 - constant resistor with one asymmetrical additional tap;

Fig 1.1 Symbols of ERE in electrical, radio engineering and automation circuits

33 - non-polarized oxide capacitor;

34 - pass-through capacitor (arc denotes a housing, an external electrode);

35 - variable capacitor (arrow indicates the rotor);

36 - trimmer capacitor, general designation;

37 - varicond;

38 - noise suppression capacitor;

39 - LED;

40 - tunnel diode;

41 - lighting and signal incandescent lamp;

42 - electric bell;

43 - galvanic or battery cell;

44 - electrical communication line with one branch;

45 - electrical communication line with two branches;

46 - a group of wires connected to one point of electrical connection. Two wires;

47 - four wires connected to one electrical connection point;

48 - a battery of galvanic cells or a rechargeable battery;

49 - coaxial cable. The screen is connected to the body;

50 - winding of a transformer, autotransformer, choke, magnetic amplifier;

51 - working winding of the magnetic amplifier;

52 - control winding of the magnetic amplifier;

53 - transformer without a core (magnetic circuit) with permanent coupling (dots indicate the beginning of the windings);

54 - transformer with a magnetodielectric core;

55 - inductor, choke without magnetic circuit;

56 - single-phase transformer with a ferromagnetic magnetic core and a screen between the windings;

57 - single-phase three-winding transformer with a ferromagnetic magnetic circuit with a tap in the secondary winding;

58 - single-phase autotransformer with voltage regulation;

59 - fuse;

60 - fuse switch;

61 - fuse disconnector;

62 - detachable pin connection;

63 - amplifier (the direction of signal transmission indicates the apex of the triangle at horizontal line communication);

64 - pin of detachable contact connection;

Fig 1.1 Symbols of ERE in electrical radio engineering and automation circuits

65 - socket of a detachable contact connection,

66 - contact of a dismountable connection, for example, using a clip

67 - contact of a non-separable connection, for example, carried out by soldering

68 - push-button single-pole push-button switch with self-resetting closing contact

69 - contact of the switching device opening, general designation

70 - closing contact of a switching device (switch, relay), general designation. The switch is single-pole.

71 - changeover contact of the switching device, general designation. Single pole double throw switch.

72- three-position changeover contact with neutral position

73 - closing contact without self-return

74 - push-button switch with break contact

75 - push-button exhaust switch with NO contact

76 - push-button switch with button return,

77 - push-button exhaust switch with break contact

78 - push-button switch with return by pressing the button a second time,

79 - electrical relay with normally open and changeover contacts,

80 - relay polarized in one direction of current in a winding with a neutral position

81 - relay polarized in both directions of current in the winding with a neutral position

82 - electric thermal relay without self-return, with a return by pressing the button a second time,

83 - detachable single-pole connection

84 - socket of a five-wire pin detachable connection

85 - pin of the pin detachable coaxial connection

86 - socket of contact connection

87 - pin four-wire connection

88 - socket of a four-wire connection

89 - jumper switching opening circuit

Table 1.1. Letter designations of circuit elements

Continuation of table 1.1

Content:

In order to correctly read and understand what this or that diagram or drawing related to electricity means, you need to know how the icons and symbols depicted on them are deciphered. A large amount of information contains the letter designations of elements in electrical circuits, determined by various regulatory documents. All of them are displayed in Latin characters in the form of one or two letters.

One-letter symbolism of elements

Letter codes corresponding to individual types of elements most widely used in electrical circuits are combined into groups designated by one symbol. Letter designations correspond to GOST 2.710-81. For example, the letter "A" refers to the "Devices" group, which consists of lasers, amplifiers, telecontrol devices and others.

In the same way, the group denoted by the symbol "B" is deciphered. It consists of devices that convert non-electrical quantities into electrical quantities, which do not include generators and power supplies. This group is complemented by analog or multi-digit converters as well as indicating or measuring sensors. The components themselves included in the group are represented by microphones, loudspeakers, pickups, detectors of ionizing radiation, thermoelectric sensing elements, etc.

All letter designations corresponding to the most common elements are combined in a special table for ease of use:

The first alphabetic character required to be reflected in the marking	Group of basic types of elements and devices	Elements that make up the group (the most typical examples)
	Devices	Lasers, masers, telecontrol devices, amplifiers.
	Apparatus for converting non-electrical quantities into electrical (without generators and power supplies), analog and multi-charge converters, sensors for indications or measurements	Microphones, loudspeakers, pickups, ionizing radiation detectors, sensitive thermoelectric elements.
	Capacitors
	Micro assemblies, integrated circuits	Digital and analog integrated circuits, memory and delay devices, logic elements.
	Miscellaneous elements	Various types of lighting devices and heating elements.
	Fuse designation in the diagram, arresters, protective devices	Fuses, arresters, discrete current and voltage protection elements.
	Power supplies, generators, quartz oscillators	Rechargeable batteries, power supplies on an electrochemical and electrothermal basis.
	Devices for signals and indications	Indicators, light and sound signaling devices
	Contactors, relays, starters	Voltage and current relays, time relays, electric thermal relays, magnetic starters, contactors.
	Chokes, inductors	Chokes in fluorescent lighting.
	Engines	DC and AC motors.
	Measuring instruments and equipment	Counters, clocks, showing, registering and measuring instruments.
		Power circuit breakers, short-circuits, disconnectors.
	Resistors
Pulse counters
Frequency meters
Active energy meters
Reactive energy meters
Recording devices
Action time meters, hours
Voltmeters
Wattmeters
	Switches and disconnectors in power circuits	Circuit breakers
		Short-circuits
		Disconnectors
	Resistors	Thermistors
		Potentiometers
		Measuring shunts
		Varistors
	Switching devices in measurement, control and signaling circuits	Switches and switches
		Push-button switches
		Automatic switches
		Switches triggered by various factors: From level
		From pressure
		From position (travel)
		From the speed
		From temperature
	Transformers, autotransformers	Current transformers
		Electromagnetic stabilizers
		Voltage transformers
	Communication devices, converters of non-electrical quantities into electrical	Modulators
		Demodulators
		Discriminators
		Frequency generators, inverters, frequency converters
	Semiconductor and vacuum devices	Diodes, Zener diodes
		Electrovacuum devices
		Transistors
		Thyristors
	Antennas, microwave lines and elements	Taps
		Short-circuits
		Transformers, phase shifters
		Attenuators
	Contact connections	Sliding contacts, current collectors
		Dismountable connections
		High frequency connectors
	Mechanical devices with electromagnetic drive	Electromagnets
		Electromagnetic brakes
		Electromagnetic clutches
		Electromagnetic holders or plates
	Limiters, terminal devices, filters	Limiters
		Quartz filters

In addition, GOST 2.710-81 defines Special symbols to designate each item.

Conditional graphic symbols of electronic components in circuits

How to learn to read schematic diagrams

Those who have just started studying electronics are faced with the question: "How to read schematic diagrams?" The ability to read circuit diagrams is necessary for self-assembly of an electronic device and not only. What is the schematic diagram? A schematic diagram is a graphical representation of a collection of electronic components connected by live conductors. The development of any electronic device begins with the development of its schematic diagram.

It is on schematic diagram it is shown how exactly the radio components need to be connected in order to end up with a finished electronic device that is capable of performing certain functions. To understand what is shown on the schematic diagram, you need, firstly, to know the symbolic designation of those elements that make up electronic circuit... Any radio component has its own conventional graphic designation - UGO ... As a rule, it displays a structural device or purpose. So, for example, the conventional graphic designation of the speaker very accurately conveys the real device of the speaker. This is how the speaker is indicated in the diagram.

Agree, very similar. This is what the symbol for the resistor looks like.

An ordinary rectangle, inside which its power can be indicated (In this case, a 2 W resistor, as evidenced by two vertical lines). But this is how an ordinary capacitor of constant capacity is designated.

These are fairly simple elements. But semiconductor electronic components, such as transistors, microcircuits, triacs, have a much more sophisticated image. So, for example, any bipolar transistor has at least three terminals: base, collector, emitter. In a conventional image of a bipolar transistor, these conclusions are shown in a special way. To distinguish a resistor from a transistor on the diagram, firstly, you need to know the conventional image of this element and, preferably, its basic properties and characteristics. Since each radio component is unique, certain information can be graphically encrypted in the conventional image. For example, it is known that bipolar transistors can have different structures: p-n-p or n-p-n... Therefore, UGO transistors of different structures are somewhat different. Take a look ...

Therefore, before starting to understand the circuit diagrams, it is advisable to get acquainted with the radio components and their properties. So it will be easier to figure out what is still shown in the diagram.

On our site, it has already been told about many radio components and their properties, as well as their symbol on the diagram. If you forgot - welcome to the "Start" section.

In addition to conventional images of radio components, other clarifying information is indicated on the schematic diagram. If you look closely at the diagram, you will notice that next to each conventional image of the radio component there are several Latin letters, for example, VT , BA , C etc. This is an abbreviated letter designation of a radio component. This is done so that when describing the operation or setting up the circuit, one can refer to one or another element. It is not difficult to notice that they are also numbered, for example, like this: VT1, C2, R33, etc.

It is clear that there can be as many radio components of the same type in the circuit. Therefore, in order to streamline all this, numbering is applied. The numbering of parts of the same type, for example resistors, is carried out on schematic diagrams according to the "AND" rule. This is, of course, just an analogy, but quite illustrative. Take a look at any diagram and you will see that radio parts of the same type are numbered starting from the left. top corner, then in order the numbering goes down, and then again the numbering starts at the top, and then down, and so on. Now remember how you write the letter "I". I think everything is clear with this.

What else to tell about the schematic diagram? Here's what. On the diagram, next to each radio component, its main parameters or standard type are indicated. Sometimes this information is placed in a table to make the concept easier to understand. For example, next to the image of a capacitor, as a rule, its nominal capacity in microfarads or picofarads is indicated. The rated operating voltage may also be indicated if relevant.

Next to the UGO of the transistor, the type of the transistor is usually indicated, for example, KT3107, KT315, TIP120, etc. In general, for any semiconductor electronic components such as microcircuits, diodes, zener diodes, transistors, the component type is indicated, which is supposed to be used in the circuit.

For resistors, only its nominal resistance in kilo-ohms, ohms or megohms is usually indicated. The power rating of the resistor is encrypted with oblique lines inside the rectangle. Also, the power of the resistor in the diagram and on its image may not be indicated. This means that the power of the resistor can be anything, even the smallest, since the operating currents in the circuit are insignificant and even the smallest resistor available in the industry can withstand them.

Here in front of you the simplest scheme two-stage audio frequency amplifier. The diagram shows several elements: a power battery (or just a battery) GB1 ; fixed resistors R1 , R2 , R3 , R4 ; power switch SA1 , electrolytic capacitors C1 , C2 ; fixed capacitor C3 ; high impedance speaker BA1 ; bipolar transistors VT1 , VT2 structures n-p-n... As you can see, I am referring to a specific element in the diagram using Latin letters.

What can we learn by looking at this diagram?

Any electronics operate on electric current, therefore, the current source from which the circuit is powered must be indicated on the diagram. The source of current can be both a battery and an AC mains or a power supply.

So. Since the amplifier circuit is powered by a GB1 DC battery, therefore, the battery has a polarity: plus "+" and minus "-". On the conventional image of the battery, we see that the polarity is indicated next to its terminals.

Polarity. It is worth mentioning separately. For example, electrolytic capacitors C1 and C2 have polarity. If we take a real electrolytic capacitor, then on its case it is indicated which of its conclusions is positive and which is negative. And now, the most important thing. When self-assembling electronic devices, it is necessary to observe the polarity of connecting the electronic parts in the circuit. Failure to do so simple rule will lead to inoperability of the device and, possibly, other undesirable consequences. Therefore, do not be lazy from time to time to glance at the schematic diagram, according to which you assemble the device.

The diagram shows that to assemble the amplifier, you will need constant resistors R1 - R4 with a power of at least 0.125 W. This can be seen from their designation.

You can also notice that the resistors R2 * and R4 * marked with an asterisk * ... This means that the nominal resistance of these resistors must be selected in order to establish optimal operation of the transistor. Usually, in such cases, instead of resistors, the value of which needs to be selected, a variable resistor with a resistance slightly greater than the value of the resistor indicated in the diagram is temporarily installed. To determine the optimal operation of the transistor in this case, a milliammeter is connected to the open circuit of the collector. The place on the diagram where you need to connect the ammeter is indicated on the diagram like this. The current is also indicated, which corresponds to the optimal operation of the transistor.

Recall that to measure the current, the ammeter is included in the open circuit.

Next, turn on the amplifier circuit with the SA1 switch and begin to change the resistance with a variable resistor R2 *... At the same time, the readings of the ammeter are monitored and the milliammeter shows a current of 0.4 - 0.6 milliamperes (mA). At this, the setting of the mode of the transistor VT1 is considered complete. Instead of the variable resistor R2 *, which we installed in the circuit at the time of adjustment, a resistor with such a nominal resistance is installed, which is equal to the resistance of the variable resistor obtained as a result of adjustment.

What is the conclusion from all this long narration about the establishment of the work of the circuit? And the conclusion is that if on the diagram you see any radio component with an asterisk (for example, R5 *), this means that in the process of assembling the device according to this schematic diagram, it will be necessary to establish the work of certain sections of the circuit. How to establish the operation of the device, as a rule, is mentioned in the description of the schematic diagram itself.

If you look at the amplifier circuit, you can also notice that there is such a symbol on it.

This designation shows the so-called common wire... In technical documentation, it is called a body. As you can see, the common wire in the shown amplifier circuit is the wire that is connected to the negative "-" terminal of the GB1 battery. For other circuits, the common wire can also be the wire that is connected to the plus of the power supply. In circuits with bipolar power, the common wire is indicated separately and is not connected to either the positive or negative terminal of the power supply.

Why is the "common wire" or "case" indicated on the diagram?

All measurements in the circuit are carried out with respect to the common wire, with the exception of those that are negotiated separately, and also peripheral devices are connected with respect to it. The common wire carries the total current consumed by all elements of the circuit.

The common wire of the circuit in reality is often connected to metal case an electronic device or a metal chassis on which the printed circuit boards are mounted.

It should be understood that the common wire is not the same as the "ground". " Earth"- this is grounding, that is, an artificial connection to the ground by means of a grounding device. It is indicated in the diagrams as follows.

In some cases, the common wire of the device is connected to ground.

As already mentioned, all radio components in the schematic diagram are connected using current-carrying conductors. The live conductor can be a copper wire or a copper foil track on printed circuit board... A live conductor in the schematic diagram is indicated by a regular line. Like this.

The places of soldering (electrical connection) of these conductors to each other, or to the terminals of radio components are shown with a bold point. Like this.

It should be understood that on a schematic diagram, a dot indicates only the connection of three or more conductors or terminals. If the diagram shows the connection of two conductors, for example, the output of a radio component and a conductor, then the diagram would be overloaded with unnecessary images and at the same time its informativeness and conciseness would be lost. Therefore, it should be understood that in real scheme there may be electrical connections that are not shown in the circuit diagram.

The next part deals with connections and connectors, repetitive and mechanically connected elements, shielded parts and conductors. Click " Further"...