Wiring & Schematic Diagram Symbols and Meanings
Browse 482 electrical and electronic symbols with meanings, terminals, example circuits, and verified IEC or ANSI notes where available. Public reference pages are free to browse; editor pack access depends on the current plan.
Download the full electrical symbols chart as a free PDF or open the printable chart.
DIY & Residential symbols
| Symbol | Meaning |
|---|---|
| 240V Outlet symbol | The 240V Outlet symbol represents a 240-volt alternating-current receptacle used in residential and. |
| AFCI Breaker symbol | The AFCI Breaker symbol represents an Arc-Fault Circuit Interrupter circuit breaker in residential and. |
| AFCI/GFCI Combo Breaker symbol | The AFCI/GFCI Combo Breaker symbol represents a dual-protection circuit breaker that combines Arc-Fault. |
| Alarm Panel symbol | The Alarm Panel symbol represents the control unit of an intrusion alarm system — drawn as a rectangle with a. |
| Armored Cable (MC/BX) symbol | The Armored Cable (MC/BX) symbol represents a type of electrical wiring in which insulated conductors are. |
| Attic Fan symbol | The Attic Fan symbol represents an electrically powered ventilation fan installed in an attic, gable, or roof. |
| Baseboard Heater symbol | The Baseboard Heater symbol represents a fixed electric resistance convection heater — drawn as a long, low. |
| Bathroom Exhaust Fan symbol | The Bathroom Exhaust Fan symbol represents a ceiling- or wall-mounted ventilation fan used in wiring diagrams. |
| Battery Bank symbol | The Battery Bank symbol represents multiple storage batteries connected as one DC source — drawn as two. |
| CCTV Camera symbol | The CCTV Camera symbol represents a fixed surveillance camera — drawn as a trapezoid camera body with a lens. |
| Ceiling Fan symbol | The Ceiling Fan symbol represents a ceiling-mounted motor-driven ventilation fan — depicted in residential. |
| Ceiling Fan with Light symbol | The Ceiling Fan with Light symbol represents a combined ceiling-mounted fan and integral light kit — shown in. |
| Circuit Breaker symbol | The Circuit Breaker symbol represents an automatically operated electrical switch designed to interrupt fault. |
| CO Detector symbol | The CO Detector symbol represents a carbon monoxide detection and alarm device — required by NFPA 720, UL. |
| Conduit Run symbol | The Conduit Run symbol represents a section of electrical raceway — drawn as a single or double line with. |
| Dimmer Switch symbol | The Dimmer Switch symbol represents a variable light-control device in wiring diagrams, depicted as a. |
| Disconnect symbol | The Disconnect symbol represents a manually operated safety switching device in wiring diagrams that provides. |
| Doorbell / Chime symbol | The Doorbell / Chime symbol represents the sounder or chime unit in a residential low-voltage doorbell wiring. |
| Doorbell Button symbol | The Doorbell Button symbol represents a normally-open (NO) momentary pushbutton switch in residential wiring. |
| Doorbell Camera symbol | The Doorbell Camera symbol represents a smart video doorbell device in residential and commercial wiring. |
| Double-Pole Breaker symbol | The Double-Pole Breaker symbol represents a two-pole circuit breaker in residential and light commercial. |
| Dual Run Capacitor symbol | The Dual Run Capacitor symbol represents two motor-run capacitors sharing one can and one common terminal —. |
| Duplex Outlet symbol | The Duplex Outlet symbol represents a standard dual-receptacle 120 V AC wall socket used in residential and. |
| Electric Cooker / Range symbol | The Electric Cooker / Range symbol represents a high-power fixed cooking appliance — drawn as a square with. |
| Emergency Light symbol | The Emergency Light symbol represents a self-contained battery-backup egress lighting unit — drawn as a. |
| EV Charger Outlet (NEMA 14-50) symbol | The EV Charger Outlet (NEMA 14-50) symbol represents a 240 V AC, 50 A, 4-wire receptacle used as the. |
| Exit Sign symbol | The Exit Sign symbol represents a continuously illuminated, battery-backed egress marking fixture — drawn as. |
| Fence Energizer symbol | The Fence Energizer symbol represents the pulse generator of an electric fence — drawn as a rectangle with a. |
| Fluorescent Fixture symbol | The Fluorescent Fixture symbol represents a gas-discharge lighting unit containing one or more fluorescent. |
| Garage Door Opener symbol | The Garage Door Opener symbol represents a motor-driven residential or commercial door operator unit that. |
| Garbage Disposal symbol | The Garbage Disposal symbol represents an electrically-powered kitchen food-waste disposer unit installed. |
| Gate Motor symbol | The Gate Motor symbol represents an electromechanical gate operator — drawn as a motor circle marked 'M'. |
| Generator symbol | The Generator symbol represents an electromechanical device that converts mechanical energy into electrical. |
| GFCI Breaker symbol | The GFCI Breaker symbol represents a combination circuit breaker and ground-fault current interrupter. |
| GFCI Outlet symbol | The GFCI Outlet symbol represents a Ground Fault Circuit Interrupter receptacle — a mains-voltage outlet with. |
| Ground symbol | The Ground symbol represents the reference node in a circuit diagram at which voltage is defined as zero. |
| Hot Tub Disconnect symbol | The Hot Tub Disconnect symbol represents a listed outdoor disconnect means — typically a lockable non-fusible. |
| Junction Box symbol | The Junction Box symbol represents an enclosed electrical enclosure in wiring diagrams used to house and. |
| Landscape Light (Low Voltage) symbol | The Landscape Light (Low Voltage) symbol represents a low-voltage outdoor luminaire in wiring diagrams. |
| LED Driver symbol | The LED Driver symbol represents the AC-to-DC power conversion unit that supplies regulated voltage or. |
| LED Strip symbol | The LED Strip symbol represents a flexible low-voltage tape of series-parallel LED groups — drawn as a long. |
| Light Fixture symbol | The Light Fixture symbol (also called a luminaire symbol) represents a permanently wired ceiling, wall, or. |
| Low Voltage Transformer symbol | The Low Voltage Transformer symbol represents a step-down isolation transformer that converts 120 V AC mains. |
| Main Panel symbol | The Main Panel symbol represents the primary electrical distribution panel (also called the load centre. |
| Meter Base symbol | The Meter Base symbol represents the utility-owned socket enclosure mounted at the service entrance that. |
| Motion Sensor symbol | The Motion Sensor symbol represents a detection device — most commonly a passive infrared (PIR) sensor or. |
| Occupancy Sensor symbol | The Occupancy Sensor symbol represents an electronic detection device that automatically controls lighting or. |
| Outdoor Lamp Post symbol | The Outdoor Lamp Post symbol represents a freestanding exterior luminaire mounted on a vertical post — used. |
| Outlet symbol | The Outlet symbol (also called a receptacle or socket symbol) represents a fixed electrical socket mounted in. |
| Path Light symbol | The Path Light symbol represents a low-voltage landscape luminaire installed along walkways, garden paths, or. |
| Photocell / Dusk Sensor symbol | The Photocell / Dusk Sensor symbol represents an automatic light-control device, designated P or LS in. |
| Pool Pump symbol | The Pool Pump symbol represents a single-phase electric motor-driven centrifugal pump used in swimming-pool. |
| Prepaid Meter symbol | The Prepaid Meter symbol represents a pay-before-use kWh energy meter with an integral supply switch — drawn. |
| Pull Box symbol | The Pull Box symbol represents an enclosed metal or non-metallic junction enclosure installed in a conduit. |
| Range / Dryer Outlet symbol | The Range / Dryer Outlet symbol represents a 240 V AC (or 120/240 V AC) heavy-duty receptacle for connecting. |
| Range Hood symbol | The Range Hood symbol represents an electrically powered kitchen exhaust ventilation appliance that captures. |
| Recessed Can Light (6-inch) symbol | The Recessed Can Light (6-inch) symbol represents a 6-inch diameter recessed luminaire — also called a can. |
| Recessed Light symbol | The Recessed Light symbol represents a recessed ceiling luminaire — also called a can light, downlight, or. |
| Romex Cable symbol | The Romex Cable symbol represents a non-metallic sheathed (NM-B) electrical cable used in residential wiring. |
| Service Entrance symbol | The Service Entrance symbol represents the utility supply interface point in an electrical wiring diagram —. |
| Smart Switch (WiFi) symbol | The Smart Switch (WiFi) symbol represents a WiFi-connected electronically-controlled switch module used in. |
| Smoke Detector symbol | The Smoke Detector symbol represents a life-safety sensing device in electrical and fire-alarm wiring. |
| Solar Charge Controller symbol | The Solar Charge Controller symbol represents the DC power regulator between a photovoltaic array and a. |
| Solar Inverter symbol | The Solar Inverter symbol represents a grid-tie or off-grid photovoltaic inverter drawn as a labeled. |
| Solar Panel symbol | The Solar Panel symbol represents a photovoltaic module drawn as a rectangular grid with two output terminals. |
| Subpanel symbol | The Subpanel symbol represents a secondary electrical distribution panel — also called a sub-distribution. |
| Switch (3-Way) symbol | The Switch (3-Way) symbol represents a single-pole double-throw (SPDT) wall switch used in residential and. |
| Switch (SPST) symbol | The Switch (SPST) symbol represents a Single-Pole Single-Throw switch — a two-terminal device that either. |
| Tandem / Twin Breaker symbol | The Tandem / Twin Breaker symbol represents a half-size double circuit breaker that occupies a single panel. |
| Thermostat symbol | The Thermostat symbol represents a temperature-activated switching or control device—depicted in wiring. |
| Timer Switch symbol | The Timer Switch symbol represents a time-controlled switching device—drawn as a rectangle or box with a. |
| Track Light symbol | The Track Light symbol represents a linear lighting system—drawn in electrical and lighting layout diagrams. |
| Track Lighting Head symbol | The Track Lighting Head symbol represents an individual adjustable-aim luminaire fixture—drawn as a small. |
| Transfer Switch symbol | The Transfer Switch symbol represents an electrical switching device—drawn as a three-terminal block or. |
| Under-Cabinet Light symbol | The Under-Cabinet Light symbol represents a low-profile, hardwired or plug-in luminaire mounted beneath. |
| USB Outlet symbol | The USB Outlet symbol represents a mains wall receptacle that incorporates one or more built-in USB charging. |
| Weatherproof Box symbol | The Weatherproof Box symbol represents an outdoor-rated electrical enclosure used in wiring diagrams to. |
| Weatherproof Outlet symbol | The Weatherproof Outlet symbol represents an outdoor-rated electrical receptacle installed in a sealed. |
| Whole House Surge Protector symbol | The Surge Protector symbol represents a point-of-use Surge Protective Device (SPD Type 3) connected between a. |
| Whole-House Fan symbol | The Whole-House Fan symbol represents a large ceiling-mounted ventilation fan used in residential wiring. |
| Wire Nut symbol | The Wire Nut symbol represents a twist-on wire connector used in wiring diagrams to denote the physical. |
| Wire Raceway / Molding symbol | The Wire Raceway / Molding symbol represents a surface-mounted cable management channel used in wiring. |
| Wire Splice symbol | The Wire Splice symbol represents a permanent electrical connection between two conductor ends in a wiring. |
| Zone Valve symbol | The Zone Valve symbol represents a motorized valve that opens and closes hot-water flow to one heating zone. |
Hobbyist & Electronics symbols
| Symbol | Meaning |
|---|---|
| 4x4 Matrix Keypad symbol | The 4×4 Matrix Keypad symbol represents a 16-key input device organised in four rows and four columns, where. |
| 555 Timer IC symbol | The 555 Timer IC symbol represents a versatile monolithic timing integrated circuit — originally designated. |
| 74HC595 Shift Register symbol | The 74HC595 Shift Register symbol represents an 8-bit serial-in, parallel-out (SIPO) shift register. |
| 8-Channel Relay Board symbol | The 8-Channel Relay Board symbol represents a pre-assembled module containing eight independent. |
| 8x8 LED Matrix symbol | The 8×8 LED Matrix symbol represents a 64-LED display module arranged in an 8-row by 8-column grid, where. |
| A4988 Stepper Driver symbol | The A4988 Stepper Driver symbol represents a bipolar stepper motor driver module drawn as a labeled rectangle. |
| ACS712 Current Sensor Module symbol | The ACS712 Current Sensor Module symbol represents a Hall-effect-based integrated current sensing module that. |
| ADS1115 ADC Module symbol | The ADS1115 ADC Module symbol represents a precision 16-bit, 4-channel, I2C-interface analog-to-digital. |
| Arduino Uno symbol | The Arduino Uno symbol represents the Arduino Uno R3 microcontroller development board — a popular. |
| ATmega328 (DIP) symbol | The ATmega328 (DIP) symbol represents the Microchip (formerly Atmel) ATmega328P 8-bit AVR microcontroller in. |
| Battery symbol | The Battery symbol represents a DC voltage source composed of one or more electrochemical cells, drawn as. |
| Bluetooth Module (HC-05) symbol | The Bluetooth Module (HC-05) symbol represents a serial-to-Bluetooth bridge IC module used in circuit. |
| BMP280 Pressure Sensor symbol | The BMP280 Pressure Sensor symbol represents a Bosch Sensortec digital barometric pressure and temperature. |
| Boost Converter Module symbol | The Boost Converter Module symbol represents a DC-DC step-up power module that raises an input voltage to a. |
| Breadboard Power Rail symbol | The Breadboard Power Rail symbol represents the dual-bus power distribution row on a solderless breadboard. |
| Buck Converter Module symbol | The Buck Converter Module symbol represents a DC-DC step-down power module that reduces an input voltage to a. |
| CAN Bus Transceiver symbol | The CAN Bus Transceiver symbol represents an integrated circuit — such as the Microchip MCP2551 or TI. |
| Capacitive Touch Sensor symbol | The Capacitive Touch Sensor symbol represents a proximity-sensing module—drawn as a rectangular block with. |
| Capacitor symbol | The Capacitor symbol represents a passive two-terminal component that stores electrical energy in an electric. |
| CD4051 Analog MUX symbol | The CD4051 Analog MUX symbol represents an 8-to-1 analog multiplexer/demultiplexer integrated circuit that. |
| Cell (Single) symbol | The Cell symbol represents a single electrochemical cell — the basic unit of DC supply — drawn per IEC 60617. |
| Crystal Oscillator symbol | The Crystal Oscillator symbol represents a quartz crystal resonator — drawn as a rectangle (the piezoelectric. |
| Current Sensor (ACS712) symbol | The Current Sensor (ACS712) symbol represents a Hall-effect-based linear current sensor integrated circuit. |
| DC Barrel Jack symbol | The DC Barrel Jack symbol represents a coaxial power connector—consisting of a cylindrical sleeve. |
| DC Motor symbol | The DC Motor symbol represents a direct-current electric motor — drawn as a circle containing the letter M. |
| DHT11 Temperature/Humidity symbol | The DHT11 Temperature/Humidity symbol represents a low-cost digital sensor module that measures ambient. |
| Diode symbol | The Diode symbol represents a two-terminal semiconductor device that allows current to flow predominantly in. |
| DIP Switch symbol | The DIP Switch symbol represents an array of independent SPST switches packaged in a dual in-line package —. |
| DPDT Switch symbol | The DPDT Switch symbol represents a double-pole, double-throw switch — two electrically independent SPDT. |
| DS18B20 Temperature Sensor symbol | The DS18B20 Temperature Sensor symbol represents Maxim Integrated's (now Analog Devices) DS18B20 digital. |
| Electric Bell symbol | The Electric Bell symbol represents an electromagnetically operated audible signalling device with two. |
| Electrolytic Capacitor symbol | The Electrolytic Capacitor symbol represents a polarised capacitor that uses an electrolyte to achieve high. |
| ESP32 symbol | The ESP32 symbol represents the Espressif Systems ESP32 dual-core 32-bit microcontroller module with. |
| ESP8266 Module symbol | The ESP8266 Module symbol represents the Espressif Systems ESP8266 single-core 80/160 MHz Wi-Fi SoC module. |
| Ferrite Bead symbol | The Ferrite Bead symbol represents a passive two-terminal EMI suppression component that attenuates. |
| Fingerprint Sensor symbol | The Fingerprint Sensor symbol represents a biometric identification module (such as the R307 or FPM10A. |
| Fuse symbol | The Fuse symbol represents a protective two-terminal device that interrupts a circuit by melting its. |
| Galvanometer symbol | The Galvanometer symbol represents a sensitive moving-coil instrument for detecting and measuring small. |
| H-Bridge IC (L298N) symbol | The H-Bridge IC (L298N) symbol represents the STMicroelectronics L298N dual full-bridge motor driver. |
| Hall Effect Sensor symbol | The Hall Effect Sensor symbol represents a three-terminal semiconductor transducer — with VCC (supply), GND. |
| HC-SR501 PIR Module symbol | The HC-SR501 PIR Module symbol represents a passive infrared motion-detection module drawn as a labeled. |
| Header Pins (Female) symbol | The Header Pins (Female) symbol represents a multi-pin socket connector — with receptacle contacts designed. |
| Header Pins (Male) symbol | The Header Pins (Male) symbol represents a row of protruding male pin connectors — typically 2.54 mm pitch —. |
| Inductor / Coil symbol | The Inductor (Coil) symbol represents a passive component that stores energy in a magnetic field — drawn as a. |
| IR Receiver symbol | The IR Receiver symbol represents a three-terminal integrated infrared demodulator module — such as the. |
| IR Remote Control symbol | The IR Remote Control symbol represents a handheld infrared transmitter device used in circuit diagrams to. |
| IR Transmitter LED symbol | The IR Transmitter LED symbol represents an infrared-emitting diode (IRED) in circuit diagrams, drawn as the. |
| Joystick Module symbol | The Joystick Module symbol represents a dual-axis analog input device in circuit diagrams, drawn as a labeled. |
| JST Connector (2-pin) symbol | The JST Connector (2-pin) symbol represents a 2-pole miniature wire-to-board or wire-to-wire connector from. |
| JST Connector (4-pin) symbol | The JST Connector (4-pin) symbol represents a 4-circuit miniature wire-to-board connector from JST's PH, XH. |
| Lamp / Light Bulb symbol | The Lamp / Light Bulb symbol represents a two-terminal light-emitting load (Terminals A and B. |
| LCD 16x2 Module symbol | The LCD 16x2 Module symbol represents a Hitachi HD44780-compatible alphanumeric liquid-crystal display module. |
| LED symbol | The LED (Light-Emitting Diode) symbol represents a polarised semiconductor device that emits light when. |
| LiPo Battery symbol | The LiPo Battery symbol represents a rechargeable lithium polymer electrochemical cell or pack delivering a. |
| LiPo Charger Module (TP4056) symbol | The LiPo Charger Module (TP4056) symbol represents a lithium-ion/lithium-polymer battery charging. |
| LM2596 Power Module symbol | The LM2596 Power Module symbol represents a buck (step-down) switching voltage regulator module based on the. |
| LM317 (Adjustable Regulator) symbol | The LM317 symbol represents a three-terminal adjustable positive linear voltage regulator IC that delivers an. |
| LM7805 (5V Regulator) symbol | The LM7805 symbol represents a three-terminal fixed positive 5 V linear voltage regulator IC that delivers a. |
| Load Cell (HX711) symbol | The Load Cell (HX711) symbol represents a strain-gauge transducer paired with an HX711 24-bit. |
| Logic Level Shifter symbol | The Logic Level Shifter symbol represents a bidirectional or unidirectional voltage-translation module that. |
| LoRa Module symbol | The LoRa Module symbol represents a long-range, low-power wireless transceiver module based on Semtech's LoRa. |
| MAX7219 LED Driver symbol | The MAX7219 LED Driver symbol represents the Maxim Integrated MAX7219 serialised 8-digit LED display driver. |
| MCP23017 GPIO Expander symbol | The MCP23017 GPIO Expander symbol represents a 16-bit I2C-controlled bidirectional digital I/O port expander. |
| Microphone symbol | The Microphone symbol represents a transducer that converts acoustic sound pressure waves into an electrical. |
| Motor Driver Module symbol | The Motor Driver Module symbol represents an integrated PWM motor controller IC or module — such as the. |
| MPU6050 IMU Module symbol | The MPU6050 IMU Module symbol represents the InvenSense MPU-6050 6-axis inertial measurement unit — a. |
| MQ-2 Gas Sensor symbol | The MQ-2 Gas Sensor symbol represents a resistive chemo-resistive gas detection module that responds to. |
| N-Channel MOSFET symbol | The N-Channel MOSFET symbol represents an enhancement-mode n-channel metal-oxide-semiconductor field-effect. |
| Neon Lamp symbol | The Neon Lamp symbol represents a two-electrode gas-discharge glow lamp with non-polarised terminals A and B. |
| NeoPixel LED Ring symbol | The NeoPixel LED Ring symbol represents an Adafruit WS2812B-based addressable RGB LED ring module in which. |
| NPN Transistor (BJT) symbol | The NPN Transistor (BJT) symbol represents an N-P-N bipolar junction transistor — a three-terminal. |
| nRF24L01 RF Module symbol | The nRF24L01 RF Module symbol represents a Nordic Semiconductor nRF24L01+ 2.4 GHz transceiver module used in. |
| OLED Display Module symbol | The OLED Display Module symbol represents an SSD1306-based 0.96-inch 128×64-pixel monochrome OLED (organic. |
| Op-Amp (DIP) symbol | The Op-Amp (DIP) symbol represents an operational amplifier packaged in a Dual In-line Package (DIP), drawn. |
| Optocoupler Module symbol | The Optocoupler Module symbol represents a PCB breakout module — incorporating a PC817 or 4N35 optocoupler. |
| P-Channel MOSFET symbol | The P-Channel MOSFET symbol represents a P-channel enhancement-mode (or depletion-mode). |
| Photodiode symbol | The Photodiode symbol represents a light-sensitive semiconductor diode with Anode and Cathode terminals. |
| Photoresistor (LDR) symbol | The Photoresistor (LDR) symbol represents a two-terminal passive resistor whose resistance decreases as. |
| Phototransistor symbol | The Phototransistor symbol represents a bipolar transistor whose base current is generated by incident light. |
| Piezo Buzzer symbol | The Piezo Buzzer symbol represents an electromechanical sound-emitting device, designated BZ or LS in. |
| PIR Motion Sensor symbol | The PIR Motion Sensor symbol represents a passive infrared detection module, commonly the HC-SR501 or. |
| PN532 NFC Module symbol | The PN532 NFC Module symbol represents a near-field communication and RFID transceiver module based on the. |
| PNP Transistor (BJT) symbol | The PNP Transistor (BJT) symbol represents a bipolar junction transistor with a p-type emitter, n-type base. |
| Portable Power Bank symbol | The Portable Power Bank symbol represents a rechargeable lithium-ion battery pack with a built-in USB charge. |
| Potentiometer symbol | The Potentiometer symbol represents a three-terminal variable resistor whose output voltage or resistance is. |
| Push Button symbol | The Push Button symbol represents a momentary-action switch with two terminals (A and B) that closes its. |
| Raspberry Pi symbol | The Raspberry Pi symbol represents the Raspberry Pi single-board computer (SBC) in schematic and wiring. |
| Reed Switch symbol | The Reed Switch symbol represents a magnetically operated, hermetically sealed contact with two terminals (A. |
| Relay Module symbol | The Relay Module symbol represents a single-channel electromechanical relay on a breakout PCB, depicted in. |
| Relay SPDT symbol | The Relay SPDT symbol represents a Single-Pole Double-Throw electromagnetic relay — defined in IEC 60617-07. |
| Resistor symbol | The Resistor symbol represents a passive two-terminal component that opposes the flow of electric current. |
| RFID RC522 Module symbol | The RFID RC522 Module symbol represents a 13.56 MHz MFRC522-based Radio Frequency Identification. |
| RGB LED (4-pin) symbol | The RGB LED (4-pin) symbol represents a four-terminal Light Emitting Diode package containing three separate. |
| Rotary Encoder symbol | The Rotary Encoder symbol represents an electromechanical position-sensing device that converts angular shaft. |
| Rotary Encoder Module symbol | The Rotary Encoder Module symbol represents a mechanical incremental rotary encoder board (commonly the. |
| Rotary Switch symbol | The Rotary Switch symbol represents a multi-position selector in which a rotating wiper connects one Common. |
| RTC DS3231 Module symbol | The RTC DS3231 Module symbol represents a real-time clock module built around the Maxim DS3231. |
| Schottky Diode symbol | The Schottky Diode symbol represents a metal-semiconductor junction diode with a lower forward voltage drop. |
| Screw Terminal (2-pos) symbol | The Screw Terminal (2-pos) symbol represents a 2-position screw-clamp connector used in circuit diagrams to. |
| Screw Terminal (3-pos) symbol | The Screw Terminal (3-pos) symbol represents a 3-position screw-clamp connector in circuit and wiring. |
| SD Card Module symbol | The SD Card Module symbol represents a microSD/SD card interface breakout module in electronic schematic. |
| Servo Motor symbol | The Servo Motor symbol represents a closed-loop actuator that uses pulse-width modulation (PWM) position. |
| Seven-Segment Display symbol | The Seven-Segment Display symbol represents a numeric LED (or LCD) display module consisting of seven. |
| Shift Register (8-bit) symbol | The Shift Register (8-bit) symbol represents a serial-in/parallel-out (SIPO) digital storage register that. |
| Slide Switch symbol | The Slide Switch symbol represents a maintained-contact SPDT (single-pole double-throw) switch in which a. |
| Solar Cell (Small) symbol | The Solar Cell (Small) symbol represents a single photovoltaic cell drawn as a labeled rectangle with a 'PV'. |
| Solenoid Coil symbol | The Solenoid Coil symbol represents an electromagnetic actuator coil that converts current into linear. |
| Speaker symbol | The Speaker symbol represents an electro-acoustic transducer drawn as a rectangular voice-coil body connected. |
| Stepper Motor symbol | The Stepper Motor symbol represents a digital-pulse-driven electromechanical actuator drawn as a circle. |
| Supercapacitor symbol | The Supercapacitor symbol represents an electric double-layer capacitor (EDLC) — a polarised energy-storage. |
| TCS3200 Color Sensor symbol | The TCS3200 Color Sensor symbol represents an integrated colour-to-frequency converter IC — manufactured by. |
| TFT LCD Display symbol | The TFT LCD Display symbol represents a Thin-Film Transistor Liquid Crystal Display module — an active-matrix. |
| Thermistor (NTC) symbol | The Thermistor (NTC) symbol represents a thermally-sensitive resistor whose resistance decreases as. |
| Trimpot / Trimmer symbol | The Trimpot / Trimmer symbol represents a miniature, board-mounted variable resistor used for one-time or. |
| Ultrasonic Sensor symbol | The Ultrasonic Sensor symbol represents a module that measures distance by emitting a 40 kHz ultrasonic pulse. |
| USB Connector symbol | The USB Connector symbol represents a Universal Serial Bus interface connector used for data communication. |
| Variable Resistor symbol | The Variable Resistor symbol represents a two-terminal passive component whose resistance can be adjusted. |
| Varistor (MOV) symbol | The Varistor (MOV) symbol represents a voltage-dependent, nonlinear resistor — most commonly a Metal Oxide. |
| Voltage Divider Module symbol | The Voltage Divider Module symbol represents a pre-built resistor-based scaling module with a three-terminal. |
| Voltage Regulator symbol | The Voltage Regulator symbol represents a three-terminal linear or switching power-regulation block. |
| Wemos D1 Mini symbol | The Wemos D1 Mini symbol represents a compact ESP8266-based Wi-Fi development module in circuit and schematic. |
| WS2812 Addressable LED symbol | The WS2812 Addressable LED symbol represents a self-contained RGB LED module with an integrated control IC. |
| Zener Diode symbol | The Zener Diode symbol represents a two-terminal semiconductor device that conducts normally in the forward. |
Professional & Analog/Digital symbols
| Symbol | Meaning |
|---|---|
| 4-Bit Counter symbol | The 4-Bit Counter symbol represents a synchronous digital integrated circuit that increments (or decrements). |
| 7-Segment Decoder symbol | The 7-Segment Decoder symbol represents a combinational logic integrated circuit that converts a 4-bit BCD. |
| ADC Block symbol | The ADC Block symbol represents an Analog-to-Digital Converter functional block in circuit and system. |
| Amplifier Block symbol | The Amplifier Block symbol represents a generic signal amplification stage in circuit and system block. |
| AND Gate symbol | The AND Gate symbol represents a two-input (or more) combinational logic gate whose output is HIGH (logic 1). |
| Antenna symbol | The Antenna symbol represents a transducer that converts between guided electromagnetic waves (in a. |
| Astable Multivibrator symbol | The Astable Multivibrator symbol represents a free-running oscillator circuit that continuously switches. |
| Balun symbol | The Balun symbol represents a transformer-based or transmission-line device that converts between a balanced. |
| Bandpass Filter Block symbol | The Bandpass Filter Block symbol represents a two-port frequency-selective network that passes signals within. |
| Bandstop Filter Block symbol | The Bandstop Filter Block symbol represents a two-port frequency-selective network that attenuates signals. |
| BCD Counter symbol | The BCD Counter symbol represents a digital integrated circuit that counts input clock pulses and outputs the. |
| Boost Converter (Topology) symbol | The Boost Converter (Topology) symbol represents the fundamental switched-mode power supply circuit topology. |
| Buck Converter (Topology) symbol | The Buck Converter (Topology) symbol represents the fundamental switched-mode power supply circuit topology. |
| Buffer symbol | The Buffer symbol represents a non-inverting digital logic gate that reproduces its input signal at its. |
| CCCS (Dependent Current Source) symbol | The CCCS symbol represents a current-controlled current source — a dependent source whose output current. |
| CCVS (Dependent Voltage Source) symbol | The CCVS symbol represents a current-controlled voltage source — a dependent source whose output voltage. |
| Center-Tap Transformer symbol | The Center-Tap Transformer symbol represents a transformer whose secondary winding has an additional. |
| Charge Pump symbol | The Charge Pump symbol represents a switched-capacitor DC-DC converter block — used in power electronics. |
| Clamper Circuit symbol | The Clamper Circuit symbol represents an electronic signal-conditioning block — also known as a DC restorer —. |
| Colpitts Oscillator symbol | The Colpitts Oscillator symbol represents an LC feedback oscillator circuit block — named after Edwin. |
| Comparator symbol | The Comparator symbol represents an analog circuit element — drawn as a triangle (op-amp outline) with a. |
| Crystal Oscillator Module symbol | The Crystal Oscillator Module symbol represents a complete pre-packaged clock source — drawn as a rectangular. |
| Current Mirror symbol | The Current Mirror symbol represents a two-terminal active circuit block — drawn as a rectangular functional. |
| Current Source symbol | The Current Source symbol represents an ideal two-terminal circuit element that forces a constant or. |
| D Flip-Flop symbol | The D Flip-Flop symbol represents an edge-triggered bistable storage element that captures the logic level. |
| DAC Block symbol | The DAC Block symbol represents a Digital-to-Analogue Converter, a circuit element that translates an n-bit. |
| Darlington Pair symbol | The Darlington Pair symbol represents a compound transistor configuration in which two bipolar junction. |
| Decoder (3:8) symbol | The Decoder (3:8) symbol represents a combinational logic functional block that decodes a 3-bit binary input. |
| Demultiplexer (DEMUX) symbol | The Demultiplexer (DEMUX) symbol represents a combinational logic functional block that routes a single data. |
| DIAC symbol | The DIAC symbol represents a bidirectional two-terminal thyristor that conducts current in either direction. |
| Differential Amplifier symbol | The Differential Amplifier symbol represents an analogue circuit block that amplifies the voltage difference. |
| Differentiator symbol | The Differentiator symbol represents an analogue op-amp circuit block whose output voltage is proportional to. |
| Digital Comparator symbol | The Digital Comparator symbol represents a combinational logic functional block that compares two multi-bit. |
| Directional Coupler symbol | The Directional Coupler symbol represents a passive four-port RF and microwave network component that samples. |
| Emitter Follower symbol | The Emitter Follower symbol represents a common-collector bipolar junction transistor (BJT) amplifier stage. |
| Encoder (Priority) symbol | The Encoder (Priority) symbol represents a combinational logic block that converts 2^n input lines into an. |
| Envelope Detector symbol | The Envelope Detector symbol represents an analogue signal-processing block that extracts the slowly-varying. |
| Flyback Converter symbol | The Flyback Converter symbol represents an isolated DC-DC switching power supply topology that uses a coupled. |
| FPGA Block symbol | The FPGA Block symbol represents a Field-Programmable Gate Array integrated circuit — a reconfigurable logic. |
| Frequency Divider symbol | The Frequency Divider symbol represents a digital circuit block that outputs a clock signal whose frequency. |
| FSK Modulator symbol | The FSK Modulator symbol represents a digital modulation block that encodes binary data by shifting a carrier. |
| Full-Wave Rectifier symbol | The Full-Wave Rectifier symbol represents a four-diode bridge circuit that converts both half-cycles of an AC. |
| Gate Driver symbol | The Gate Driver symbol represents a dedicated integrated circuit that amplifies a low-power logic control. |
| Gilbert Cell Mixer symbol | The Gilbert Cell Mixer symbol represents a doubly-balanced active analog multiplier circuit — typically built. |
| Ground (Chassis) symbol | The Ground (Chassis) symbol represents a connection point tied to the conductive enclosure or mechanical. |
| Ground (Signal) symbol | The Ground (Signal) symbol represents the internal circuit voltage reference — commonly called common ground. |
| H-Bridge symbol | The H-Bridge symbol represents a four-switch power topology — named for its H-shaped circuit arrangement of. |
| Half-Wave Rectifier symbol | The Half-Wave Rectifier symbol represents a two-terminal circuit block containing a single diode that. |
| Highpass Filter Block symbol | The Highpass Filter Block symbol represents a two-terminal frequency-selective network that passes signals. |
| IGBT symbol | The IGBT (Insulated Gate Bipolar Transistor) symbol represents a three-terminal voltage-controlled power. |
| Instrumentation Amplifier symbol | The Instrumentation Amplifier symbol represents a precision differential-input amplifier with high. |
| Integrator symbol | The Integrator symbol represents an analog signal-processing circuit — typically an op-amp with a capacitor. |
| JK Flip-Flop symbol | The JK Flip-Flop symbol represents a clocked bistable sequential logic element in circuit diagrams, drawn as. |
| Linear Regulator Block symbol | The Linear Regulator Block symbol represents a three-terminal voltage-regulation circuit or IC that maintains. |
| Log Amplifier symbol | The Log Amplifier symbol represents an analogue circuit block whose output voltage is proportional to the. |
| Low Noise Amplifier symbol | The Low Noise Amplifier (LNA) symbol represents a two-port active amplifier block placed at the input of a. |
| Lowpass Filter Block symbol | The Lowpass Filter Block symbol represents a two-terminal analogue or digital signal-processing element that. |
| Monostable Multivibrator symbol | The Monostable Multivibrator symbol represents a single-output pulse-generating circuit block — also called a. |
| Multiplexer (MUX) symbol | The Multiplexer (MUX) symbol represents a digital or analog combinational logic circuit that selects one of. |
| Multiplexer 4:1 symbol | The Multiplexer 4:1 symbol represents a four-input, one-output digital data selector circuit — commonly. |
| N-Channel JFET symbol | The N-Channel JFET symbol represents a junction field-effect transistor whose N-type conductive channel. |
| NAND Gate symbol | The NAND Gate symbol represents a universal logic gate that produces a LOW (0) output only when all of its. |
| Noise Source symbol | The Noise Source symbol represents an idealized or physical circuit element that generates a specified. |
| NOR Gate symbol | The NOR Gate symbol represents a digital logic gate whose output is LOW (logic 0) whenever any one or more of. |
| NOT Gate / Inverter symbol | The NOT Gate / Inverter symbol represents a single-input, single-output digital logic gate whose output is. |
| NPN Transistor symbol | The NPN Transistor symbol represents an NPN bipolar junction transistor (BJT) — drawn as a circle (device. |
| Op-Amp symbol | The Op-Amp symbol represents an operational amplifier — a high-gain, differential-input voltage amplifier —. |
| Optocoupler symbol | The Optocoupler symbol represents an optoelectronic isolation device — standardised in IEC 60747-5 and. |
| OR Gate symbol | The OR Gate symbol represents a digital logic gate — standardised in IEC 60617-12 and ANSI Y32.2/IEEE 315 —. |
| P-Channel JFET symbol | The P-Channel JFET symbol represents a junction field-effect transistor whose P-type conductive channel. |
| Peak Detector symbol | The Peak Detector symbol represents an analog signal-processing circuit block — built around an operational. |
| Phase Detector symbol | The Phase Detector symbol represents an analog or digital circuit block — a key sub-component of a. |
| Pi Attenuator symbol | The Pi Attenuator symbol represents a passive resistive network in a π (pi) topology — one series resistor. |
| PLL Block symbol | The PLL Block symbol represents a Phase-Locked Loop — a closed-loop feedback circuit used in electronic and. |
| Power Amplifier Block symbol | The Power Amplifier Block symbol represents a high-power signal-amplification stage in a circuit diagram. |
| Precision Rectifier symbol | The Precision Rectifier symbol represents an op-amp-based circuit that rectifies AC signals to DC with. |
| Precision Voltage Reference symbol | The Precision Voltage Reference symbol represents a two- or three-terminal active circuit element used in. |
| PTAT Current Source symbol | The PTAT Current Source symbol represents a Proportional To Absolute Temperature current source — an analog. |
| RAM Block symbol | The RAM Block symbol represents a Random Access Memory module or functional block in digital circuit. |
| RF Attenuator symbol | The RF Attenuator symbol represents a passive two-port network — labelled ATT or −x dB in circuit diagrams. |
| RF Log Detector symbol | The RF Log Detector symbol represents an integrated circuit block that converts RF or IF signal power into a. |
| RF Mixer symbol | The RF Mixer symbol represents a three-port non-linear circuit element — depicted as a circle with an X. |
| Sample and Hold symbol | The Sample and Hold symbol represents an analog circuit that captures (samples) the instantaneous value of an. |
| SAR ADC symbol | The SAR ADC symbol represents a Successive Approximation Register analog-to-digital converter that converts. |
| Schmitt Trigger symbol | The Schmitt Trigger symbol represents an analog or digital circuit element with two distinct input switching. |
| Schmitt Trigger NAND symbol | The Schmitt Trigger NAND symbol represents a two-input NAND logic gate with integrated Schmitt trigger. |
| Sigma-Delta ADC symbol | The Sigma-Delta ADC symbol represents a high-resolution analogue-to-digital converter that uses oversampling. |
| Signal Generator symbol | The Signal Generator symbol represents a test-equipment source that produces a defined periodic waveform —. |
| Signal Limiter symbol | The Signal Limiter symbol represents a two-terminal active or passive circuit block that clips or clamps an. |
| Snubber Network symbol | The Snubber Network symbol represents a passive RC (resistor-capacitor) or RCD circuit placed in parallel. |
| Squelch Circuit symbol | The Squelch Circuit symbol represents a noise-gating signal-processing block drawn as a labeled rectangle. |
| SR Latch symbol | The SR Latch symbol represents a basic bistable sequential logic element drawn as a labeled rectangle with. |
| Summing Amplifier symbol | The Summing Amplifier symbol represents an operational-amplifier circuit configured with multiple inverting. |
| T Attenuator symbol | The T Attenuator symbol represents a passive resistive network in a T (tee) topology — two series resistors. |
| T Flip-Flop symbol | The T Flip-Flop symbol represents a Toggle flip-flop — a clocked sequential logic element that changes. |
| Test Point symbol | The Test Point symbol represents a dedicated accessible node in a circuit — typically a small solder pad. |
| Thyristor / SCR symbol | The Thyristor / SCR symbol represents a silicon controlled rectifier — a four-layer (PNPN) power. |
| Transformer symbol | The Transformer symbol represents a passive electromagnetic device — drawn as two sets of coil loops (or. |
| Transimpedance Amplifier symbol | The Transimpedance Amplifier symbol represents a current-to-voltage converter circuit—drawn as a standard. |
| Tri-State Buffer symbol | The Tri-State Buffer symbol represents a digital logic gate that drives its output to logic HIGH, logic LOW. |
| TRIAC symbol | The TRIAC symbol represents a bidirectional, gate-triggered thyristor used in AC power-control circuits. |
| Varactor Diode symbol | The Varactor Diode symbol represents a PN-junction diode operated in reverse bias as a voltage-variable. |
| VCCS (Dependent Current Source) symbol | The VCCS symbol represents a voltage-controlled current source — a dependent source whose output current. |
| VCO Block symbol | The VCO Block symbol represents a Voltage-Controlled Oscillator functional block with a control voltage input. |
| VCVS (Dependent Voltage Source) symbol | The VCVS symbol represents a voltage-controlled voltage source — a dependent source whose output voltage. |
| VGA DAC Block symbol | The VGA DAC Block symbol represents a digital-to-analog converter stage used in circuit diagrams to depict. |
| Voltage Divider symbol | The Voltage Divider symbol represents two resistors connected in series between an input voltage (Vin) and. |
| Voltage Doubler symbol | The Voltage Doubler symbol represents a switched-capacitor or diode-capacitor charge-pump circuit block with. |
| Voltage Source (AC) symbol | The Voltage Source (AC) symbol represents an ideal two-terminal source of sinusoidal alternating voltage. |
| Voltage Source (DC) symbol | The Voltage Source (DC) symbol represents an ideal two-terminal source of constant direct voltage, defined in. |
| Wheatstone Bridge symbol | The Wheatstone Bridge symbol represents a four-resistor diamond-shaped measurement circuit used in schematic. |
| Wien Bridge Oscillator symbol | The Wien Bridge Oscillator symbol represents a low-distortion RC sinusoidal oscillator circuit used in. |
| XNOR Gate symbol | The XNOR Gate symbol represents a digital logic gate whose output is logic HIGH (1) when all inputs are equal. |
| XOR Gate symbol | The XOR Gate symbol represents a digital logic gate whose output is logic HIGH (1) when its inputs differ. |
| Zero-Crossing Detector symbol | The Zero-Crossing Detector symbol represents an analogue or mixed-signal circuit block that produces a narrow. |
Industrial & Control symbols
| Symbol | Meaning |
|---|---|
| 3-Phase Motor symbol | The 3-Phase Motor symbol represents a three-phase AC induction or synchronous motor, depicted in IEC 60617-06. |
| 3-Phase Plug (CEE / Industrial) symbol | The 3-Phase Plug (CEE / Industrial) symbol represents an industrial polyphase electrical connector—drawn as a. |
| 3-Phase Supply symbol | The 3-Phase Supply symbol represents a three-phase alternating-current power source in electrical schematics. |
| 3-Pole Contactor symbol | The 3-Pole Contactor symbol represents a heavy-duty electromechanical switching device with three main power. |
| 3.5mm Audio Jack (TRS) symbol | The 3.5mm Audio Jack (TRS) symbol represents a 3-conductor miniature phone connector in circuit diagrams. |
| 4-Pole Contactor symbol | The 4-Pole Contactor symbol represents an electromechanical switching device with four independently-switched. |
| Alternator symbol | The Alternator symbol represents an electromechanical AC generator — most commonly the automotive charging. |
| Ammeter symbol | The Ammeter symbol represents a current-measuring instrument inserted in series with a circuit to indicate. |
| Automotive Relay (5-pin) symbol | The Automotive Relay symbol represents the standard 12 V SPDT 'mini' (Bosch-style) relay used throughout. |
| Autotransformer symbol | The Autotransformer symbol represents a single-winding transformer in which part of the winding serves as. |
| Battery Charger symbol | The Battery Charger symbol represents an AC-to-DC converter that rectifies mains power and regulates it. |
| BLDC / Brushless DC Motor symbol | The BLDC / Brushless DC Motor symbol represents a three-phase permanent-magnet synchronous motor that is. |
| Bus Tie Switch symbol | The Bus Tie Switch symbol represents a normally-open switching device used in electrical distribution. |
| Buzzer / Audible Alarm symbol | The Buzzer / Audible Alarm symbol represents a polarised electromechanical or piezoelectric sound-emitting. |
| Cable Entry / Gland symbol | The Cable Entry / Gland symbol represents a mechanical cable entry fitting — used in wiring and installation. |
| Cable Lug / Crimp Terminal symbol | The Cable Lug / Crimp Terminal symbol represents a mechanical crimped or compression terminal — standardised. |
| Cable Tray symbol | The Cable Tray symbol represents a continuous rigid structural system — standardised under IEC 61537 and NEMA. |
| Capacitor Bank symbol | The Capacitor Bank symbol represents a group of capacitors connected in parallel (or series-parallel) as a. |
| Changeover Contact (SPDT) symbol | The Changeover Contact (SPDT) symbol represents a single-pole double-throw relay or switch contact —. |
| Check Valve symbol | The Check Valve symbol represents a one-way (non-return) valve — standardised in ISO 1219-1 for hydraulic and. |
| Circuit Breaker (MCB) symbol | The Circuit Breaker (MCB) symbol represents a Miniature Circuit Breaker — drawn as a rectangle containing a. |
| Compressor symbol | The Compressor symbol represents the hermetic motor-compressor of a refrigeration, air-conditioning, or. |
| Contactor Coil symbol | The Contactor Coil symbol represents the electromagnetic operating coil of a contactor or relay, drawn as a. |
| Contactor NC Contact symbol | The Contactor NC Contact symbol represents a normally-closed (NC) auxiliary contact of a contactor, drawn as. |
| Contactor NO Contact symbol | The Contactor NO Contact symbol represents a normally-open (NO) auxiliary contact of a contactor, drawn as. |
| Current Limiting Reactor symbol | The Current Limiting Reactor symbol represents a series air-core or iron-core inductor — drawn as a series of. |
| Current Transformer (CT) symbol | The Current Transformer (CT) symbol represents an instrument transformer that produces a secondary current. |
| DIN Rail symbol | The DIN Rail symbol represents the standardised metal mounting track—defined in IEC 60715 as the TS 35. |
| DIN Rail End Stop symbol | The DIN Rail End Stop symbol represents a mechanical end-bracket accessory mounted on a DIN rail (TS 35 / EN. |
| Disconnect Switch / Isolator symbol | The Disconnect Switch / Isolator symbol represents a manually operated switching device in industrial. |
| Distributed I/O Module symbol | The Distributed I/O Module symbol represents a remote input/output device in industrial automation schematics. |
| Door Interlock Switch symbol | The Door Interlock Switch symbol represents a safety switching device in electrical and control system. |
| Earth Leakage Relay symbol | The Earth Leakage Relay symbol represents a protective relay that monitors residual ground-fault current in. |
| Emergency Stop symbol | The Emergency Stop symbol represents a safety-rated manually-actuated electromechanical device that. |
| Energy Meter (kWh) symbol | The Energy Meter (kWh) symbol represents a revenue-grade electrical energy measurement device that. |
| Fire Alarm Panel symbol | The Fire Alarm Panel symbol represents the fire alarm control unit (FACP/FACU) at the heart of a building's. |
| Float Switch symbol | The Float Switch symbol represents a level-sensing switch whose contacts open or close based on liquid. |
| Flow Control Valve symbol | The Flow Control Valve symbol represents a variable-restriction valve that regulates the volumetric flow rate. |
| Flow Switch symbol | The Flow Switch symbol represents a pilot device whose contacts change state when fluid flow in a pipe or. |
| Fluorescent / HID Ballast symbol | The Fluorescent / HID Ballast symbol represents a current-limiting and arc-stabilising control device for. |
| Foot Switch symbol | The Foot Switch symbol represents a foot-operated pilot device that opens or closes contacts when the. |
| Fuse symbol | The Fuse symbol represents a single-use overcurrent protection device containing a fusible element that melts. |
| Fuse Terminal Block symbol | The Fuse Terminal Block symbol represents a modular DIN-rail-mounted terminal block with an integrated. |
| Ground / Earth symbol | The Ground / Earth symbol represents a reference node connected to the Earth via a grounding electrode —. |
| Grounding Switch symbol | The Grounding Switch symbol represents a mechanically-operated isolating switch used in high-voltage and. |
| Guitar Output Jack (TS) symbol | The Guitar Output Jack (TS) symbol represents a mono 1/4-inch (6.35 mm) TS (Tip-Sleeve) phone jack connector. |
| Guitar Pickup symbol | The Guitar Pickup symbol represents an electromagnetic transducer, used in electric guitar and bass circuits. |
| Harmonic Filter symbol | The Harmonic Filter symbol represents a power-quality conditioning device — either passive (LC tuned. |
| Heating Cable / Heat Trace symbol | The Heating Cable / Heat Trace symbol represents a self-regulating or constant-wattage resistive cable. |
| Heating Element symbol | The Heating Element symbol represents a resistive load that converts electrical energy directly into heat by. |
| HMI Touchscreen Panel symbol | The HMI Touchscreen Panel symbol represents a human-machine interface display unit — a touchscreen or. |
| Horn / Siren symbol | The Horn / Siren symbol represents an electromechanical or electronic audible-signalling device — a horn. |
| Hydraulic Cylinder symbol | The Hydraulic Cylinder symbol represents a linear actuator that converts hydraulic pressure into. |
| Hydraulic Motor symbol | The Hydraulic Motor symbol represents the rotary actuator that converts hydraulic fluid power back into. |
| Hydraulic Pump symbol | The Hydraulic Pump symbol represents the component that converts mechanical shaft power into hydraulic fluid. |
| Hydraulic Reservoir symbol | The Hydraulic Reservoir symbol represents the vented tank that stores the system's fluid and performs. |
| Ignition Coil symbol | The Ignition Coil symbol represents an automotive inductive transformer that steps up a 12 V DC battery. |
| Ignition Switch (Multi-Position) symbol | The Ignition Switch (Multi-Position) symbol represents a key-operated rotary switch in an automotive or. |
| Industrial Network Switch symbol | The Industrial Network Switch symbol represents a managed or unmanaged Ethernet switch used in industrial. |
| Inverter (DC-AC) symbol | The Inverter (DC-AC) symbol represents a power electronics device that converts direct current (DC) at its. |
| Isolation Transformer symbol | The Isolation Transformer symbol represents a transformer with a 1:1 turns ratio used in circuit diagrams to. |
| Key Switch symbol | The Key Switch symbol represents a mechanically-operated switch that requires a physical key to actuate in. |
| Knife Disconnect Switch symbol | The Knife Disconnect Switch symbol represents a manually-operated visible-blade isolating switch in circuit. |
| Lightning Arrester symbol | The Lightning Arrester symbol represents a surge-protection device connected between a live conductor (Line). |
| Lightning Rod / Air Terminal symbol | The Lightning Rod / Air Terminal symbol represents a pointed metal conductor elevated above a structure to. |
| Limit Switch NC symbol | The Limit Switch NC symbol represents a mechanically-actuated, normally-closed electrical switch that carries. |
| Limit Switch NO symbol | The Limit Switch NO symbol represents a mechanically-actuated, normally-open electrical switch whose contacts. |
| Line Reactor symbol | The Line Reactor symbol represents a series-connected three-phase or single-phase inductor (choke) inserted. |
| Magneto (Engine Generator) symbol | The Magneto (Engine Generator) symbol represents a self-contained permanent-magnet alternator that generates. |
| Manual Pull Station symbol | The Manual Pull Station symbol represents a manually operated fire alarm initiating device — called a manual. |
| MCCB (Molded Case CB) symbol | The MCCB (Moulded Case Circuit Breaker) symbol represents a self-contained, factory-assembled overcurrent. |
| Motor Protection CB symbol | The Motor Protection CB (circuit breaker) symbol represents a combined motor protection circuit breaker —. |
| Motor Protection Relay symbol | The Motor Protection Relay symbol represents an electronic or electromechanical protective relay that. |
| Motor Starter (DOL) symbol | The Motor Starter (DOL) symbol represents a Direct-On-Line motor starter in industrial wiring and schematic. |
| Multi-Level Terminal Block symbol | The Multi-Level Terminal Block symbol represents a double-deck or multi-level DIN-rail-mounted terminal block. |
| NEMA L14-30 (4-prong twist-lock) symbol | The NEMA L14-30 (4-prong twist-lock) symbol represents a 30-ampere, 125/250-volt locking plug and receptacle. |
| Neutral Rail symbol | The Neutral Rail symbol represents a common return conductor bus in an AC electrical distribution system. |
| OBD-II Connector (16-pin) symbol | The OBD-II Connector (16-pin) symbol represents the standardised SAE J1962 Data Link Connector (DLC) found in. |
| Overload Contact NC symbol | The Overload Contact NC symbol represents a normally-closed (NC) auxiliary contact of a thermal or electronic. |
| Overload Contact NO symbol | The Overload Contact NO symbol represents a normally-open (NO) auxiliary contact of a thermal or electronic. |
| Panel Fan symbol | The Panel Fan symbol represents a forced-ventilation cooling fan mounted inside an electrical enclosure or. |
| Panel Thermostat symbol | The Panel Thermostat symbol represents a temperature-sensing control device mounted inside an electrical. |
| Phase Sequence Relay symbol | The Phase Sequence Relay symbol represents a three-phase protective device, designated K in schematics, that. |
| Photoelectric Sensor symbol | The Photoelectric Sensor symbol represents an industrial proximity and detection device, typically designated. |
| Pilot Light / Indicator symbol | The Pilot Light / Indicator symbol represents a panel-mounted visual signalling device, designated H or HL in. |
| PLC CPU symbol | The PLC CPU symbol represents the central processing unit module of a Programmable Logic Controller. |
| PLC Input Module symbol | The PLC Input Module symbol represents a digital input interface module of a Programmable Logic Controller. |
| PLC Output Module symbol | The PLC Output Module symbol represents a digital output interface module of a Programmable Logic Controller. |
| Plug Connector Female symbol | The Plug Connector Female symbol represents a socket-type electrical connector — commonly called a receptacle. |
| Plug Connector Male symbol | The Plug Connector Male symbol represents a pin-type electrical connector — commonly called a plug — used in. |
| Pneumatic 3/2 Valve symbol | The Pneumatic 3/2 Valve symbol represents a directional control valve with 3 ports and 2 switching positions. |
| Pneumatic 5/2 Valve symbol | The Pneumatic 5/2 Valve symbol represents a directional control valve with 5 ports and 2 switching positions. |
| Pneumatic Cylinder (Double Acting) symbol | The Pneumatic Cylinder (Double Acting) symbol represents a linear actuator driven by compressed air on both. |
| Pneumatic Cylinder (Single Acting) symbol | The Pneumatic Cylinder (Single Acting) symbol represents a linear actuator driven by compressed air on the. |
| Power Distribution Block symbol | The Power Distribution Block symbol represents a bus-bar or terminal assembly that accepts a single. |
| Power Factor Controller symbol | The Power Factor Controller symbol represents an automatic power-factor-correction (APFC) relay that measures. |
| Power Meter symbol | The Power Meter symbol represents an instrument that measures real power (kW), reactive power (kvar). |
| Power Rail symbol | The Power Rail symbol represents a common distribution conductor in an industrial control-panel schematic. |
| Power Supply 24V DC symbol | The Power Supply 24V DC symbol represents a switched-mode or linear AC-to-DC power supply that converts mains. |
| Pressure Regulator symbol | The Pressure Regulator symbol represents a pneumatic or hydraulic device that reduces and maintains a. |
| Pressure Switch symbol | The Pressure Switch symbol represents an electromechanical or electronic device that opens or closes an. |
| PROFINET Connector symbol | The PROFINET Connector symbol represents an Industrial Ethernet network interface port used in PROFINET. |
| Proximity Sensor (Capacitive) symbol | The Proximity Sensor (Capacitive) symbol represents a non-contact electronic sensor that detects the presence. |
| Proximity Sensor (Inductive) symbol | The Proximity Sensor (Inductive) symbol represents a non-contact electronic sensor that detects the presence. |
| Pump (Motor-driven) symbol | The Pump symbol represents an electrically driven pump — typically a pool pump or centrifugal pump — in. |
| Push Button NC symbol | The Push Button NC symbol represents a momentary normally-closed (NC) push button — standardised in IEC. |
| Push Button NO symbol | The Push Button NO symbol represents a momentary normally-open (NO) push button — standardised in IEC. |
| RCA / Phono Connector symbol | The RCA / Phono Connector symbol represents a coaxial audio/video connector — standardised informally as the. |
| RCD / RCCB symbol | The RCD / RCCB symbol represents a Residual Current Device (also called a Residual Current Circuit Breaker) —. |
| Relay Coil symbol | The Relay Coil symbol represents the electromagnetic coil of a relay — drawn as a rectangle (IEC 60617) or a. |
| Relay NC Contact symbol | The Relay NC Contact symbol represents a Normally Closed (NC) relay or contactor contact — defined in IEC. |
| Relay NO Contact symbol | The Relay NO Contact symbol represents a Normally Open (NO) relay or contactor contact — defined in IEC. |
| Relief Valve symbol | The Relief Valve symbol represents the normally closed pressure-control valve that limits maximum system. |
| Reversing Valve symbol | The Reversing Valve symbol represents the pilot-operated four-way refrigerant valve that switches a heat pump. |
| RJ45 / Ethernet Connector symbol | The RJ45 / Ethernet Connector symbol represents an 8P8C (8-position 8-contact) modular connector —. |
| RTD Temperature Sensor symbol | The RTD Temperature Sensor symbol represents a Resistance Temperature Detector — a passive sensing element. |
| Safety Interlock Switch symbol | The Safety Interlock Switch symbol represents a mechanically actuated safety switching device that monitors. |
| Safety Light Curtain symbol | The Safety Light Curtain symbol represents an electro-sensitive protective device (ESPE) that creates an. |
| Safety PLC symbol | The Safety PLC symbol represents a fail-safe programmable logic controller designed to execute. |
| Safety Relay Module symbol | The Safety Relay Module symbol represents a dedicated, certified relay module that monitors dual-channel. |
| Selector Switch 2-Position symbol | The Selector Switch 2-Position symbol represents a maintained-contact rotary or cam-operated switch that can. |
| Selector Switch 3-Position symbol | The Selector Switch 3-Position symbol represents a maintained-contact rotary switch with three discrete cam. |
| Single-Phase Motor symbol | The Single-Phase Motor symbol represents an AC electric motor powered by a single-phase supply, depicted in. |
| Soft Starter symbol | The Soft Starter symbol represents a reduced-voltage motor-starting device drawn as a labeled rectangle with. |
| Soft Starter (3-Phase) symbol | The Soft Starter (3-Phase) symbol represents a reduced-voltage motor starting device that uses anti-parallel. |
| Solenoid Valve symbol | The Solenoid Valve symbol represents an electrically operated fluid control valve drawn as a rectangle with a. |
| Spark Plug symbol | The Spark Plug symbol represents an automotive or internal combustion engine ignition device drawn with a. |
| Split-Core CT symbol | The Split-Core CT symbol represents a split-core current transformer — drawn as a circle or toroid with a gap. |
| Stack Light symbol | The Stack Light symbol represents a multi-segment machine status indicator (signal tower) whose stacked. |
| Star-Delta Starter symbol | The Star-Delta Starter symbol represents a reduced-voltage motor-starting device drawn as a labeled rectangle. |
| Starter Motor symbol | The Starter Motor symbol represents a high-current series-wound DC motor with an integral engagement solenoid. |
| Stepper Motor (4-wire bipolar) symbol | The Stepper Motor (4-wire bipolar) symbol represents a precision electromechanical actuator drawn as a circle. |
| Surge Arrester (SPD) symbol | The Surge Arrester (SPD) symbol represents a Surge Protective Device — a component connected between a line. |
| Surge Protector symbol | The Surge Protector symbol represents a surge protective device (SPD) connected between a supply conductor. |
| Switch (4-Way) symbol | The Switch (4-Way) symbol represents a double-pole double-throw (DPDT) intermediate switch used in North. |
| Switch (DPST — 4-pin Rocker) symbol | The Switch (DPST — 4-pin Rocker) symbol represents a Double-Pole Single-Throw switch that simultaneously. |
| Temperature Switch symbol | The Temperature Switch symbol represents a thermally-actuated switching device that opens or closes an. |
| Terminal Block symbol | The Terminal Block symbol represents a modular, insulated wire-termination device that provides a. |
| Thermal Overload Relay symbol | The Thermal Overload Relay symbol represents a protective device—drawn as a set of heating elements (three. |
| Thermocouple symbol | The Thermocouple symbol represents a temperature sensor consisting of two dissimilar metal wires joined at a. |
| Time Delay Relay (Off-Delay) symbol | The Time Delay Relay (Off-Delay) symbol represents an electromechanical or electronic timing relay—drawn as a. |
| Time Delay Relay (On-Delay) symbol | The Time Delay Relay (On-Delay) symbol represents an electromechanical or electronic timing relay—drawn as a. |
| Trailer Connector (4-pin Flat) symbol | The Trailer Connector (4-pin Flat) symbol represents a standardised four-circuit electrical connector used to. |
| Trailer Connector (7-pin) symbol | The Trailer Connector (7-pin) symbol represents a seven-circuit round electrical connector used to interface. |
| TV Antenna (Yagi) symbol | The TV Antenna (Yagi) symbol represents a directional, parasitic-element antenna used for receiving or. |
| Undervoltage Relay symbol | The Undervoltage Relay symbol represents a protective relay device that monitors supply voltage and trips its. |
| UPS Block symbol | The UPS Block symbol represents an Uninterruptible Power Supply unit that conditions incoming AC power. |
| Variable Transformer (Variac) symbol | The Variable Transformer (Variac) symbol represents an adjustable autotransformer in circuit diagrams. |
| VFD / Variable Frequency Drive symbol | The VFD / Variable Frequency Drive symbol represents a power-electronic drive unit used in electrical and. |
| Voltage Transformer (PT) symbol | The Voltage Transformer (PT) symbol represents an instrument potential transformer used in electrical. |
| Voltmeter symbol | The Voltmeter symbol represents a voltage-measuring instrument in circuit diagrams, depicted as a circle. |
| Water Heater / Geyser symbol | The Water Heater / Geyser symbol represents an electric storage water heater in residential and commercial. |
| Water Level Probe (3 electrodes) symbol | The Water Level Probe (3 electrodes) symbol represents a three-electrode conductivity-based liquid level. |
| Wire Crossing (No Connection) symbol | The Wire Crossing (No Connection) symbol represents two conductors that cross each other in a schematic. |
| Wire Duct / Trunking symbol | The Wire Duct / Trunking symbol represents an open-top or slotted plastic or metal channel used in wiring. |
| Wire Junction / Node symbol | The Wire Junction / Node symbol represents the point at which two or more conductors are electrically. |
| Wire Label / Marker symbol | The Wire Label / Marker symbol represents a conductor identification tag, ferrule, or sleeve in wiring. |
| X-Ray Tube symbol | The X-Ray Tube symbol represents a vacuum tube that generates ionising X-radiation by accelerating electrons. |
| XLR Connector (3-pin Audio) symbol | The XLR Connector (3-pin Audio) symbol represents a balanced, shielded 3-pin audio interconnect in circuit. |
| XNX / 4-20mA Gas Transmitter symbol | The XNX / 4-20mA Gas Transmitter symbol represents a loop-powered industrial gas detection transmitter that. |
What are electrical wiring diagram symbols and their meanings?
Wiring diagram symbols are graphics that represent electrical functions or devices, such as switches, outlets, lights, fuses, breakers, motors, resistors, relay coils, transformers, and grounds. Many are standardized by IEC or ANSI/IEEE conventions; device-specific and pictorial symbols can vary by discipline, region, and manufacturer, so the drawing legend and authoritative standard still matter.
What do the most common wiring diagram symbols mean?
A line is a conductor; a junction dot means conductors connect. Parallel lines can denote a capacitor, a coil can denote an inductor or relay coil, and decreasing horizontal lines commonly denote earth ground. Switches show contact state. Always read these in the context of the drawing legend because pictorial and manufacturer conventions vary.
Are these electrical symbols free to use?
Yes. Every symbol in all four editor packs (DIY, Hobbyist, Pro and Industrial) is free to place on every plan, including Free, and the printable reference chart is free to use. Every published meaning and reference page remains publicly browsable.
Which circuit diagram symbols do I need for GCSE physics?
GCSE physics uses the IEC-style symbols for cell, battery, switch, lamp, resistor, variable resistor, thermistor, LDR, diode, LED, ammeter, voltmeter, and fuse. All of them are in the DIY and hobbyist packs above — click any symbol for its meaning and a worked example circuit.
What circuit symbols are taught in grade 6 to grade 8 science?
Middle-school circuits use a small set: cell/battery, wire, open and closed switch, bulb (lamp), resistor, and sometimes a buzzer or motor. Start with the DIY pack — each symbol page explains what the symbol means and how to draw it correctly.
What is the difference between IEC and ANSI circuit symbols?
IEC 60617 is the international symbol database, while legacy ANSI/IEEE conventions remain common in North American drawings. A familiar difference is the resistor: a rectangle in IEC diagrams versus a zigzag in many ANSI-style diagrams. Pages identify standard-specific forms only where that content has been verified.
Can I download these electrical symbols as a PDF chart?
Yes — download the free electrical symbols chart PDF directly (all symbols with names, grouped by category), or open the printable chart and print it from your browser. Every symbol on the chart links back to its full reference page.