NO
Normally open contact
A contact shown open in the normal state defined for its device.
Schematic
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Control circuits
Contacts, coils, control devices, timing, interlocking and automation references. Explore 296 references, with original explanations and public primary sources.
NC
Normally closed contact
A contact shown closed in the normal state defined for its device.
Schematic
CO
Changeover contact
A contact arrangement switching a common connection between two contact paths.
Schematic
Coil
Relay coil
The operating element associated with a relay and its separately drawn contacts.
Schematic
KM
Contactor
An electrically operated switching device commonly used for repeated switching duties.
SLD / Schematic
PB NO
Normally open pushbutton
A pushbutton contact normally shown open before actuation.
Schematic
PB NC
Normally closed pushbutton
A pushbutton contact normally shown closed before actuation.
Schematic
E-stop
Emergency-stop operator
An identified emergency-stop operator and its documented contact arrangement.
Schematic
SS
Selector switch
An operator switch selecting between documented control positions.
Schematic
Lamp
Indicator lamp
A visual indicator associated with a documented control or equipment condition.
Schematic
PLC I/O
PLC input / output
A controller interface point connecting field signals to an identified module channel.
Schematic
R
Resistor
A resistive component with its value and purpose documented separately.
Schematic
K LATCH
Mechanically latched relay coil
A mechanically latched relay retains a documented state after the initiating electrical command is removed.
Schematic
K RESET
Relay reset coil
A reset coil releases or changes the retained state of its associated latching relay.
Schematic
SSR
Solid-state relay
A solid-state relay switches an output through semiconductor circuitry in response to a control input.
Schematic
K POL
Polarised relay coil
A polarised relay has operation or a specified response that depends on the documented electrical polarity.
Schematic
K AC
AC relay coil
An AC relay coil is intended for a specified alternating-current control supply.
Schematic
K FAST
High-speed relay
A high-speed relay has a documented operating response intended for duties where relay timing matters.
Schematic
K MEAS
Measuring relay
A measuring relay responds to a measured electrical quantity and issues an output according to its configuration.
Schematic
K DIODE
Relay coil with diode suppression
A relay with diode suppression includes a diode associated with its coil to limit the transient on de-energisation.
Schematic
K D LED
Relay coil with diode and LED
A relay assembly with diode and LED combines coil transient suppression and a visible energisation indicator.
Schematic
K CAP
Relay coil with capacitor suppression
A relay with a capacitor suppression element includes a documented capacitive network associated with the coil.
Schematic
K RC
Relay coil with RC suppression
A relay RC suppression network uses resistance and capacitance associated with the coil circuit.
Schematic
COUNT MAN
Counter relay with manual reset
A manually reset counter relay records qualifying events and retains a count until the documented reset action.
Schematic
COUNT ELEC
Counter relay with electrical reset
An electrically reset counter relay has a separate reset command or documented electronic reset mechanism.
Schematic
COUNT TOTAL
Non-resettable counter relay
A non-resettable counter records events without a normal user reset function.
Schematic
TON
On-delay timer relay
An on-delay timer postpones a specified output transition after its timing condition becomes active.
Schematic
TOFF
Off-delay timer relay
An off-delay timer holds a specified output condition for a documented period after its initiating condition is removed.
Schematic
TON NO
On-delay normally-open contact
An on-delay NO contact changes from its unoperated open state only after the associated timing condition has persisted for the documented delay.
Schematic
TON NC
On-delay normally-closed contact
An on-delay NC contact opens after the associated timing condition has persisted for its documented interval.
Schematic
TOFF NO
Off-delay normally-open contact
An off-delay NO contact retains the documented operated state for an interval after the timer trigger is removed.
Schematic
TOFF NC
Off-delay normally-closed contact
An off-delay NC contact returns to its documented normally-closed state after the delay following removal of the timing trigger.
Schematic
NO HOLD
Maintained normally-open contact
A maintained NO contact retains the actuated closed position according to its mechanism or control arrangement.
Schematic
NC HOLD
Maintained normally-closed contact
A maintained NC contact retains its actuated position until the documented return action occurs.
Schematic
NO UNLATCH
Manually unlatched NO contact
A manually unlatched NO contact includes a mechanical retaining action released by a documented manual operation.
Schematic
NC UNLATCH
Manually unlatched NC contact
A manually unlatched NC contact has a mechanical retained state and a documented manual release.
Schematic
NO EARLY
Early-make normally-open contact
An early-make NO contact closes earlier in the mechanism sequence than specified associated contacts.
Schematic
NO LATE
Late-make normally-open contact
A late-make NO contact closes later in a documented mechanism sequence than associated contacts.
Schematic
NC EARLY
Early-break normally-closed contact
An early-break NC contact opens earlier in a documented mechanical sequence than associated contacts.
Schematic
NC LATE
Late-break normally-closed contact
A late-break NC contact opens later in the documented operating sequence than specified associated contacts.
Schematic
MBB
Make-before-break changeover contact
A make-before-break changeover contact establishes the next path before releasing the previous path during its documented transfer.
Schematic
OL NC
Motor overload trip NC contact
An overload trip NC contact opens on the documented overload relay operation.
Schematic
OL NO
Motor overload alarm NO contact
An overload alarm NO contact closes on the documented overload relay operation.
Schematic
PB NO LAMP
Illuminated normally-open pushbutton
An illuminated NO pushbutton combines a manual normally-open contact function with an indication lamp.
Schematic
PB NC LAMP
Illuminated normally-closed pushbutton
An illuminated NC pushbutton combines a normally-closed manual contact with a lamp in the operator assembly.
Schematic
PB NO HOLD
Maintained normally-open pushbutton
A maintained NO pushbutton stays in its actuated condition until the documented return operation.
Schematic
PB NC HOLD
Maintained normally-closed pushbutton
A maintained NC pushbutton retains its actuated open state until the documented return action.
Schematic
KEY NO
Key-operated normally-open switch
A key-operated NO switch closes a contact through an authorised key mechanism.
Schematic
KEY NC
Key-operated normally-closed switch
A key-operated NC switch opens its reference closed contact through the key mechanism.
Schematic
KEY HOLD
Latched key-operated switch
A latched key-operated switch retains its commanded position according to the selected mechanism.
Schematic
PULL CORD
Pull-cord switch
A pull-cord switch converts a cord-operated mechanical action into an electrical contact change.
Schematic
FOOT
Foot-operated switch
A foot-operated switch uses a pedal mechanism to change an electrical contact.
Schematic
LEVER
Lever-operated switch
A lever-operated switch changes contact state through a manually operated lever.
Schematic
SEL 3 HOLD
Three-position maintained selector
A three-position maintained selector stays at the selected position until manually moved.
Schematic
SEL 3 LRET
Three-position selector returning from left
This three-position selector has a documented spring return from its left position.
Schematic
SEL 3 RRET
Three-position selector returning from right
This three-position selector returns from its right position according to its mechanism.
Schematic
SEL 3 CRET
Three-position centre-return selector
A centre-return selector returns from both outer positions to its documented central rest position.
Schematic
KEY SEL 3
Three-position key selector
A three-position key selector combines position selection with a key-operated mechanism.
Schematic
SEL 4 HOLD
Four-position maintained selector
A four-position maintained selector provides four stable operating choices.
Schematic
KEY SEL 4
Four-position key selector
A four-position key selector provides key-controlled selection among four documented positions.
Schematic
LS NO
Normally-open limit switch
A normally-open limit switch closes when the documented mechanical travel or position condition actuates it.
Schematic
LS NC
Normally-closed limit switch
A normally-closed limit switch opens when the documented mechanical position actuates it.
Schematic
LS ROLLER
Roller-operated limit switch
A roller-operated limit switch transfers equipment motion through a roller actuator to its electrical contacts.
Schematic
LS CAM
Cam-operated limit switch
A cam-operated limit switch changes its electrical contact state when a defined cam profile reaches the actuator.
Schematic
PS NO
Pressure switch NO
A pressure-operated NO switch closes when its documented pressure condition actuates the mechanism.
Schematic
PS NC
Pressure switch NC
A pressure-operated NC switch opens under its documented actuation condition.
Schematic
TS NO
Temperature switch NO
A temperature-operated NO switch changes from open to closed under its specified actuation condition.
Schematic
TS NC
Temperature switch NC
A temperature-operated NC switch opens under a documented thermal condition.
Schematic
TS SELF
Self-operating thermal switch
A self-operating thermal switch responds directly to its thermal condition rather than through a separate powered relay input.
Schematic
LS FLOAT NO
Float level switch NO
A float-operated NO level switch changes contact state through a float mechanism at a documented fluid level.
Schematic
LS FLOAT NC
Float level switch NC
A float-operated NC level switch opens when its documented level condition actuates the mechanism.
Schematic
FS LIQ
Liquid flow switch
A liquid-flow switch issues a contact state when a documented flow condition actuates it.
Schematic
FS GAS
Gas flow switch
A gas-flow switch changes contact state for a specified gas-flow condition.
Schematic
PROX IND
Inductive proximity switch
An inductive proximity switch detects a documented target without a mechanical contact actuator.
Schematic
PROX IND 3W
Three-wire inductive proximity switch
A three-wire inductive proximity switch uses separate supply, common and output conductors.
Schematic
PROX CAP
Capacitive proximity switch
A capacitive proximity switch detects a target through a change in its sensing capacitance.
Schematic
PROX MAG
Magnetic proximity switch
A magnetic proximity switch detects a documented magnetic target or field condition.
Schematic
PHOTO
Photoelectric emitter-receiver switch
A photoelectric emitter-receiver device uses an optical path to determine a switching output.
Schematic
R VAR
Variable resistor
A variable resistor provides a documented adjustable resistance in a circuit path.
SLD / Schematic
POT
Potentiometer
A potentiometer uses a movable contact on a resistive element to provide a documented adjustable divider or resistance.
SLD / Schematic
LDR
Light-dependent resistor
A light-dependent resistor changes resistance according to illumination.
SLD / Schematic
HEATER
Heating element
A heating element converts electrical energy to heat in a documented circuit.
SLD / Schematic
RC
RC network
An RC network combines resistance and capacitance in a specified circuit arrangement.
SLD / Schematic
VDR
Varistor
A varistor is a voltage-dependent resistive component used in a documented circuit, often for transient limiting.
SLD / Schematic
SHUNT
Current-measuring shunt
A current-measuring shunt produces a documented voltage drop corresponding to current through a resistive element.
SLD / Schematic
C ELEC
Electrolytic capacitor
An electrolytic capacitor has a specified capacitance, voltage rating and any documented polarity requirement.
SLD / Schematic
C FEED
Feedthrough capacitor
A feedthrough capacitor is arranged with a conductor path and a documented capacitive connection used in filtering.
SLD / Schematic
C ADJ
Adjustable capacitor
An adjustable capacitor provides a documented variable capacitance.
SLD / Schematic
D
Diode
A diode provides a semiconductor path with documented directional conduction characteristics.
Schematic
PD
Photodiode
A photodiode is a light-sensitive semiconductor device used in a documented sensing circuit.
Schematic
ZD
Zener diode
A Zener diode is a semiconductor component intended for a documented reverse-breakdown operating function.
Schematic
DIAC
DIAC
A DIAC is a bidirectional triggering semiconductor device used in a documented control circuit.
Schematic
BR 1PH
Single-phase bridge rectifier
A single-phase bridge rectifier converts its specified AC input to a DC output through a bridge arrangement.
Schematic
BR 3PH
Three-phase bridge rectifier
A three-phase bridge rectifier converts a documented three-phase AC input into a DC output.
Schematic
SCR
Silicon-controlled rectifier
An SCR is a thyristor with a gate-controlled triggering function in its documented circuit.
Schematic
GTO
Gate-turn-off thyristor
A gate-turn-off thyristor has a documented gate-controlled turn-off capability.
Schematic
TRIAC
TRIAC
A TRIAC is a bidirectional thyristor used for a documented AC switching or control function.
Schematic
TVS BI
Bidirectional breakdown diode
A bidirectional breakdown diode provides a documented voltage-limiting semiconductor path in both polarities.
Schematic
LAMP TX
Transformer-fed indicator lamp
A transformer-fed indicator lamp includes a documented internal voltage-conversion arrangement.
Schematic
LAMP TEST
Push-to-test indicator lamp
A push-to-test indicator lamp allows a documented local test of the lamp circuit.
Schematic
LAMP LED
LED indicator lamp
An LED indicator assembly provides a documented visual signal using a semiconductor light source.
Schematic
LAMP FLASH
Flashing indicator lamp
A flashing indicator lamp provides a documented intermittent visual indication.
Schematic
BEACON FLASH
Flashing beacon
A flashing beacon gives a documented conspicuous visual signal.
Schematic
BEACON ROT
Rotating beacon
A rotating beacon provides a documented rotating visual signal through its specified mechanism or assembly.
Schematic
DI
PLC digital input
A PLC digital input reads a documented discrete electrical state from field wiring.
Schematic
DO RELAY
PLC relay output
A PLC relay output switches a documented contact path through the module's relay interface.
Schematic
DO TRANS
PLC transistor output
A PLC transistor output switches a documented electronic path for a field load.
Schematic
AI
PLC analog input
A PLC analog input measures a documented voltage, current or sensor quantity.
Schematic
AO
PLC analog output
A PLC analog output provides a documented variable voltage or current signal to another device.
Schematic
TI
PLC temperature input
A PLC temperature input connects a documented RTD, thermocouple or compatible sensor through the selected module.
Schematic
GA
Power contactor
A power contactor switches a power circuit through an electrically operated mechanism.
GA objects
GA
Reversing contactor assembly
A reversing assembly uses coordinated switching devices to change a motor connection sequence.
GA objects
GA
Star-delta starter assembly
A star-delta starter arranges switching devices to change a motor winding connection during starting.
GA objects
GA
Thermal overload relay
A thermal overload relay monitors motor-circuit loading and operates associated control contacts.
GA objects
GA
Electronic motor overload relay
An electronic overload device provides the specified motor monitoring and trip functions.
GA objects
GA
Soft starter
A soft starter controls motor starting through power-electronic switching.
GA objects
VFD
Variable-frequency drive
A variable-frequency drive supplies a controlled-frequency motor output.
GA objects
GA
Drive braking resistor
A braking resistor dissipates energy when specified as part of a drive braking system.
GA objects
GA
DIN-rail AC/DC power supply
A DIN-rail power supply converts an input supply into a specified DC auxiliary supply.
GA objects
DC
DIN-rail DC/DC converter
A DC/DC converter changes a DC supply to the specified output arrangement.
GA objects
GA
DC redundancy module
A redundancy module combines specified supply paths for an auxiliary DC system.
GA objects
GA
DC buffer module
A buffer module supports a DC bus through specified short supply interruptions.
GA objects
GA
DC UPS module
A DC UPS module manages continuity of a DC auxiliary supply with its specified energy-storage interface.
GA objects
DC
Battery charger
A battery charger maintains a specified battery supply or starting battery system.
GA objects
GA
PLC CPU module
A PLC CPU executes the programmed control logic of an automation system.
GA objects
GA
PLC power module
A PLC power module supplies the specified controller and expansion system.
GA objects
GA
Digital input module
A digital input module brings discrete field states into a controller.
GA objects
GA
Digital output module
A digital output module switches or signals discrete outputs under controller command.
GA objects
GA
Analogue input module
An analogue input module receives the specified continuous measurement signals.
GA objects
GA
Analogue output module
An analogue output module sends the specified continuous command signals.
GA objects
GA
Remote I/O station
A remote I/O station places input and output interfaces away from a controller CPU.
GA objects
GA
HMI touchscreen
An HMI presents operating information and control interfaces to the user.
GA objects
GA
Industrial panel PC
An industrial panel computer provides a computing platform within an equipment arrangement.
GA objects
GA
Industrial Ethernet switch
An industrial Ethernet switch interconnects devices in the specified communication network.
GA objects
GA
Industrial VPN router
A remote-access router provides the specified network interface between control equipment and other networks.
GA objects
GA
Communication gateway
A gateway connects the documented communication protocols or network boundaries.
GA objects
GA
Interface relay module
An interface relay separates a controller signal from the specified switched circuit.
GA objects
GA
Relay socket
A relay socket supports a plug-in relay and its associated connections.
GA objects
GA
Timer relay
A timer relay changes its outputs according to the selected time function.
GA objects
GA
Safety relay module
A safety relay performs specified monitored control functions within a documented safety circuit.
GA objects
GA
Signal conditioner
A signal conditioner converts or isolates the specified instrumentation signal.
GA objects
GA
Emergency stop station
An emergency stop station houses the specified emergency-control actuator and contacts.
GA objects
GA
Pilot-light station
A pilot-light station displays the documented equipment states through its lamps.
GA objects
GA
Selector-switch station
A selector station provides the selected maintained or returning control positions.
GA objects
GA
Trapped-key interlock assembly
A trapped-key arrangement coordinates access or switching through the selected mechanical key sequence.
GA objects
GA
Door-mounted pushbutton enclosure
A local control station houses the specified operator actuators and contacts.
GA objects
BRX Series PLC
AutomationDirect BRX Series PLC
AutomationDirect BRX Series PLC is a plc cpu module product family referenced for electrical equipment layout.
GA objects
CLICK PLCs
AutomationDirect CLICK PLCs
AutomationDirect CLICK PLCs is a plc cpu module product family referenced for electrical equipment layout.
GA objects
Productivity1000 PAC
AutomationDirect Productivity1000 PAC
AutomationDirect Productivity1000 PAC is a plc cpu module product family referenced for electrical equipment layout.
GA objects
Productivity2000 PAC
AutomationDirect Productivity2000 PAC
AutomationDirect Productivity2000 PAC is a plc cpu module product family referenced for electrical equipment layout.
GA objects
Productivity3000 PAC
AutomationDirect Productivity3000 PAC
AutomationDirect Productivity3000 PAC is a plc cpu module product family referenced for electrical equipment layout.
GA objects
Terminator Field I/O
AutomationDirect Terminator Field I/O
AutomationDirect Terminator Field I/O is a remote i/o station product family referenced for electrical equipment layout.
GA objects
Protos X Field I/O
AutomationDirect Protos X Field I/O
AutomationDirect Protos X Field I/O is a remote i/o station product family referenced for electrical equipment layout.
GA objects
C-more Panels
AutomationDirect C-more Panels
AutomationDirect C-more Panels is a hmi touchscreen product family referenced for electrical equipment layout.
GA objects
C-more Micro Graphic Panels
AutomationDirect C-more Micro Graphic Panels
AutomationDirect C-more Micro Graphic Panels is a hmi touchscreen product family referenced for electrical equipment layout.
GA objects
GS and DURApulse AC drives
AutomationDirect GS and DURApulse AC drives
AutomationDirect GS and DURApulse AC drives is a variable-frequency drive product family referenced for electrical equipment layout.
GA objects
Stride VPN
AutomationDirect Stride VPN
AutomationDirect Stride VPN is a industrial vpn router product family referenced for electrical equipment layout.
GA objects
AcuAmp
AutomationDirect AcuAmp
AutomationDirect AcuAmp is a signal conditioner product family referenced for electrical equipment layout.
GA objects
GA
Fuji Electric SC contactors and thermal overload relays
Fuji Electric SC contactors and thermal overload relays is a power contactor product family referenced for electrical equipment layout.
GA objects
SC-NEXT contactors
Fuji Electric SC-NEXT contactors
Fuji Electric SC-NEXT contactors is a power contactor product family referenced for electrical equipment layout.
GA objects
Orange Line / Odyssey contactors
Fuji Electric Orange Line / Odyssey contactors
Fuji Electric Orange Line / Odyssey contactors is a power contactor product family referenced for electrical equipment layout.
GA objects
Combination starters
Fuji Electric Combination starters
Fuji Electric Combination starters is a power contactor product family referenced for electrical equipment layout.
GA objects
SK contactors and relays
Fuji Electric SK contactors and relays
Fuji Electric SK contactors and relays is a power contactor product family referenced for electrical equipment layout.
GA objects
D1SE120-xx-A3
TDK-Lambda D1SE120-xx-A3
TDK-Lambda D1SE120-xx-A3 is a din-rail ac/dc power supply product family referenced for electrical equipment layout.
GA objects
D1SE240-xx-A3
TDK-Lambda D1SE240-xx-A3
TDK-Lambda D1SE240-xx-A3 is a din-rail ac/dc power supply product family referenced for electrical equipment layout.
GA objects
D1SE480-xx-A3
TDK-Lambda D1SE480-xx-A3
TDK-Lambda D1SE480-xx-A3 is a din-rail ac/dc power supply product family referenced for electrical equipment layout.
GA objects
DBM20
TDK-Lambda DBM20
TDK-Lambda DBM20 is a dc buffer module model referenced for electrical equipment layout.
GA objects
DRB15
TDK-Lambda DRB15
TDK-Lambda DRB15 is a din-rail ac/dc power supply model referenced for electrical equipment layout.
GA objects
DRB30
TDK-Lambda DRB30
TDK-Lambda DRB30 is a din-rail ac/dc power supply model referenced for electrical equipment layout.
GA objects
DRB480
TDK-Lambda DRB480
TDK-Lambda DRB480 is a din-rail ac/dc power supply model referenced for electrical equipment layout.
GA objects
DRF960
TDK-Lambda DRF960
TDK-Lambda DRF960 is a din-rail ac/dc power supply model referenced for electrical equipment layout.
GA objects
DRM40
TDK-Lambda DRM40
TDK-Lambda DRM40 is a dc redundancy module model referenced for electrical equipment layout.
GA objects
DUSH960-1248-1M
TDK-Lambda DUSH960-1248-1M
TDK-Lambda DUSH960-1248-1M is a dc ups module model referenced for electrical equipment layout.
GA objects
QS20.241
PULS QS20.241
PULS QS20.241 is a din-rail ac/dc power supply model referenced for electrical equipment layout.
GA objects
Optidrive Eco
Invertek Drives Optidrive Eco
Invertek Drives Optidrive Eco is a variable-frequency drive product family referenced for electrical equipment layout.
GA objects
TeSys K contactors
Schneider Electric TeSys K contactors
Schneider Electric TeSys K contactors is a power contactor product family referenced for electrical equipment layout.
GA objects
TeSys Giga contactors
Schneider Electric TeSys Giga contactors
Schneider Electric TeSys Giga contactors is a power contactor product family referenced for electrical equipment layout.
GA objects
TeSys Deca overload relays
Schneider Electric TeSys Deca overload relays
Schneider Electric TeSys Deca overload relays is a thermal overload relay product family referenced for electrical equipment layout.
GA objects
PowerLogic T500 Substation Controller
Schneider Electric PowerLogic T500 Substation Controller
Schneider Electric PowerLogic T500 Substation Controller is a substation rtu product family referenced for electrical equipment layout.
GA objects
GA
Substation RTU
A substation RTU provides the specified monitoring, control and communications interface.
GA objects
Skylla-IP65
Victron Energy Skylla-IP65
Victron Energy Skylla-IP65 is a battery charger product family referenced for electrical equipment layout.
GA objects
PS2-60
Westermo PS2-60
Westermo PS2-60 is a din-rail ac/dc power supply model referenced for electrical equipment layout.
GA objects
Lynx 5612-E-F4G-T8G-LV
Westermo Lynx 5612-E-F4G-T8G-LV
Westermo Lynx 5612-E-F4G-T8G-LV is a industrial ethernet switch model referenced for electrical equipment layout.
GA objects
NO
ANSI/IEEE normally open contact symbol
IEEE-oriented graphical reference for normally open contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
NC
ANSI/IEEE normally closed contact symbol
IEEE-oriented graphical reference for normally closed contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
CO
ANSI/IEEE changeover contact symbol
IEEE-oriented graphical reference for changeover contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
Coil
ANSI/IEEE relay coil symbol
IEEE-oriented graphical reference for relay coil, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
K LATCH
ANSI/IEEE mechanically latched relay coil symbol
IEEE-oriented graphical reference for mechanically latched relay coil, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
K RESET
ANSI/IEEE relay reset coil symbol
IEEE-oriented graphical reference for relay reset coil, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
K POL
ANSI/IEEE polarised relay coil symbol
IEEE-oriented graphical reference for polarised relay coil, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
K AC
ANSI/IEEE ac relay coil symbol
IEEE-oriented graphical reference for ac relay coil, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
K DIODE
ANSI/IEEE relay coil with diode suppression symbol
IEEE-oriented graphical reference for relay coil with diode suppression, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
K RC
ANSI/IEEE relay coil with rc suppression symbol
IEEE-oriented graphical reference for relay coil with rc suppression, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
TON
ANSI/IEEE on-delay timer relay symbol
IEEE-oriented graphical reference for on-delay timer relay, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
TOFF
ANSI/IEEE off-delay timer relay symbol
IEEE-oriented graphical reference for off-delay timer relay, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
NO HOLD
ANSI/IEEE maintained normally-open contact symbol
IEEE-oriented graphical reference for maintained normally-open contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
NC HOLD
ANSI/IEEE maintained normally-closed contact symbol
IEEE-oriented graphical reference for maintained normally-closed contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
NO EARLY
ANSI/IEEE early-make normally-open contact symbol
IEEE-oriented graphical reference for early-make normally-open contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
NO LATE
ANSI/IEEE late-make normally-open contact symbol
IEEE-oriented graphical reference for late-make normally-open contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
NC EARLY
ANSI/IEEE early-break normally-closed contact symbol
IEEE-oriented graphical reference for early-break normally-closed contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
NC LATE
ANSI/IEEE late-break normally-closed contact symbol
IEEE-oriented graphical reference for late-break normally-closed contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
OL NC
ANSI/IEEE motor overload trip nc contact symbol
IEEE-oriented graphical reference for motor overload trip nc contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
OL NO
ANSI/IEEE motor overload alarm no contact symbol
IEEE-oriented graphical reference for motor overload alarm no contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
PB NO
ANSI/IEEE normally open pushbutton symbol
IEEE-oriented graphical reference for normally open pushbutton, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
PB NC
ANSI/IEEE normally closed pushbutton symbol
IEEE-oriented graphical reference for normally closed pushbutton, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
PB NO LAMP
ANSI/IEEE illuminated normally-open pushbutton symbol
IEEE-oriented graphical reference for illuminated normally-open pushbutton, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
PB NC LAMP
ANSI/IEEE illuminated normally-closed pushbutton symbol
IEEE-oriented graphical reference for illuminated normally-closed pushbutton, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
PB NO HOLD
ANSI/IEEE maintained normally-open pushbutton symbol
IEEE-oriented graphical reference for maintained normally-open pushbutton, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
PB NC HOLD
ANSI/IEEE maintained normally-closed pushbutton symbol
IEEE-oriented graphical reference for maintained normally-closed pushbutton, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
SS
ANSI/IEEE selector switch symbol
IEEE-oriented graphical reference for selector switch, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
SEL 3 HOLD
ANSI/IEEE three-position maintained selector symbol
IEEE-oriented graphical reference for three-position maintained selector, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
SEL 3 CRET
ANSI/IEEE three-position centre-return selector symbol
IEEE-oriented graphical reference for three-position centre-return selector, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
KEY SEL 3
ANSI/IEEE three-position key selector symbol
IEEE-oriented graphical reference for three-position key selector, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
SEL 4 HOLD
ANSI/IEEE four-position maintained selector symbol
IEEE-oriented graphical reference for four-position maintained selector, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
KEY SEL 4
ANSI/IEEE four-position key selector symbol
IEEE-oriented graphical reference for four-position key selector, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
LS NO
ANSI/IEEE normally-open limit switch symbol
IEEE-oriented graphical reference for normally-open limit switch, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
LS NC
ANSI/IEEE normally-closed limit switch symbol
IEEE-oriented graphical reference for normally-closed limit switch, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
LS ROLLER
ANSI/IEEE roller-operated limit switch symbol
IEEE-oriented graphical reference for roller-operated limit switch, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
PS NO
ANSI/IEEE pressure switch no symbol
IEEE-oriented graphical reference for pressure switch no, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
PS NC
ANSI/IEEE pressure switch nc symbol
IEEE-oriented graphical reference for pressure switch nc, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
TS NO
ANSI/IEEE temperature switch no symbol
IEEE-oriented graphical reference for temperature switch no, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
TS NC
ANSI/IEEE temperature switch nc symbol
IEEE-oriented graphical reference for temperature switch nc, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
LS FLOAT NO
ANSI/IEEE float level switch no symbol
IEEE-oriented graphical reference for float level switch no, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
LS FLOAT NC
ANSI/IEEE float level switch nc symbol
IEEE-oriented graphical reference for float level switch nc, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
FS LIQ
ANSI/IEEE liquid flow switch symbol
IEEE-oriented graphical reference for liquid flow switch, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
HEATER
ANSI/IEEE heating element symbol
IEEE-oriented graphical reference for heating element, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
Lamp
ANSI/IEEE indicator lamp symbol
IEEE-oriented graphical reference for indicator lamp, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
LAMP TX
ANSI/IEEE transformer-fed indicator lamp symbol
IEEE-oriented graphical reference for transformer-fed indicator lamp, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
LAMP TEST
ANSI/IEEE push-to-test indicator lamp symbol
IEEE-oriented graphical reference for push-to-test indicator lamp, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
LAMP LED
ANSI/IEEE led indicator lamp symbol
IEEE-oriented graphical reference for led indicator lamp, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
TON NO
ANSI/IEEE on-delay normally-open contact symbol
IEEE-oriented graphical reference for on-delay normally-open contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
TON NC
ANSI/IEEE on-delay normally-closed contact symbol
IEEE-oriented graphical reference for on-delay normally-closed contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
TOFF NO
ANSI/IEEE off-delay normally-open contact symbol
IEEE-oriented graphical reference for off-delay normally-open contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
TOFF NC
ANSI/IEEE off-delay normally-closed contact symbol
IEEE-oriented graphical reference for off-delay normally-closed contact, with public vendor evidence and drawing-reading notes.
IEEE / ANSI
Q070109
Positive-operation direction qualifier
A positive-operation qualifier identifies the documented mechanically imposed operating direction.
IEC
Q021301
Manual-operation qualifier
This qualifier identifies an operator action applied to the associated mechanism.
IEC
Q021302
Protected-access manual-operation qualifier
This qualifier indicates that manual access to the operating mechanism is protected or restricted.
IEC
Q021305
Pushbutton-operation qualifier
A pushbutton qualifier identifies the actuation method of a contact or device.
IEC
Q021308
Emergency-operation qualifier
An emergency-operation qualifier marks the documented emergency actuation role.
IEC
Q021304
Rotary-operation qualifier
This qualifier identifies an operating mechanism actuated by rotation.
IEC
Q021313
Key-operation qualifier
A key-operation qualifier identifies a mechanism requiring the specified key action.
IEC
Q021310
Foot-operation qualifier
This qualifier identifies actuation by a foot-operated mechanism.
IEC
Q021311
Lever-operation qualifier
A lever-operation qualifier identifies a manually moved lever mechanism.
IEC
Q021214
Crank-operation qualifier
This qualifier identifies manual operation through a crank mechanism.
IEC
Q021309
Handwheel-operation qualifier
A handwheel qualifier identifies an operating mechanism moved by a wheel.
IEC
Q021401
Liquid-level actuation qualifier
This qualifier identifies actuation responding to liquid level.
IEC
Q021402
Event-count actuation qualifier
This qualifier identifies operation related to a count of events.
IEC
Q021403
Liquid-flow actuation qualifier
A liquid-flow qualifier identifies the process input operating a device.
IEC
Q021404
Gas-flow actuation qualifier
A gas-flow qualifier identifies operation responding to gas movement.
IEC
Q021326
Motor-operation qualifier
This qualifier identifies an operating mechanism driven by a motor.
IEC
Q021327
Timed-operation qualifier
A timed-operation qualifier identifies operation influenced by the documented timing function.
IEC
Q021315
Roller-operation qualifier
This qualifier identifies contact with a roller-operated mechanism.
IEC
Q021316
Cam-operation qualifier
This qualifier identifies operation by a cam mechanism.
IEC
Q021317
Cam-profile indication
A cam-profile indication describes the mechanical profile associated with an operating sequence.
IEC
Q070106
Switch-position function qualifier
This qualifier marks the publisher's switch-position function element.
IEC
Q070105
Automatic-trip qualifier
An automatic-trip qualifier indicates that the associated mechanism can operate automatically under its documented condition.
IEC
Q070107
Spring-return qualifier
A spring-return qualifier indicates return after the specified operating force is removed.
IEC
Q070108
Maintained-position qualifier
A maintained-position qualifier indicates that the operating position remains after actuation.
IEC
Q020401R
One-way linear-motion qualifier
A linear-motion qualifier identifies movement or force in one documented direction.
IEC
Q020402
Two-way linear-motion qualifier
This qualifier identifies motion or force in both directions along a linear path.
IEC
Q101101
Transition indication
A transition indication identifies a documented change between positions or states.
IEC
Q020403
One-way rotary-motion qualifier
A rotary-motion qualifier identifies movement or torque in one direction of rotation.
IEC
Q020404
Two-way rotary-motion qualifier
This qualifier identifies a mechanism capable of rotary movement in either direction.
IEC
Q020405
Limited two-way rotary-motion qualifier
This qualifier identifies rotary movement in both directions over a limited travel.
IEC
Q020801
Thermal-effect qualifier
A thermal-effect qualifier identifies a function responding to or producing heat-related behaviour.
IEC
Q020802
Magnetic-effect qualifier
This qualifier identifies a function involving a magnetic effect.
IEC
Q020803
Magnetostrictive-effect qualifier
A magnetostrictive qualifier identifies a function using the relationship between magnetisation and mechanical deformation.
IEC
Q021207
Automatic mechanical-return indication
This indication identifies the automatic return behaviour of a mechanical control relationship.
IEC
Q021208
Mechanical stop-latch indication
A stop-latch indication identifies a mechanically retained control position.
IEC
Q021209
Mechanical stop latch in neutral state
This form identifies the neutral state of the represented stop-latch mechanism.
IEC
Q021210
Mechanical stop latch in engaged state
This form identifies an engaged stop-latch mechanism.
IEC
Q021211
Mechanical interlock between devices
A mechanical interlock indication links devices whose movements are constrained by a physical relationship.
IEC
Q1020603
Two-way latching device
This form identifies the publisher's two-way latching-device arrangement.
IEC
Q1020604
Manually released latching device
This qualifier identifies release of a latching mechanism by manual action.
IEC
Q1029603
Key-controlled two-way latching device
This form identifies a two-way latch using a documented key operation.
IEC
Q021216
Mechanical clutch connection
A clutch qualifier identifies a selectively coupled mechanical relationship.
IEC
Q021217
Disconnected mechanical coupling
This indication identifies the disconnected state of a mechanical coupling.
IEC
Q021218
Engaged mechanical coupling
This indication identifies engagement between the represented mechanical elements.
IEC
Q021223
Mechanical gear connection
A gear-connection indication identifies transmission through a gearing relationship.
IEC
HIN1P29
Clock indication
A clock indication identifies a time display or clock function in the circuit documentation.
IEC
HIN1P33
Minute-pulse clock contact
This representation identifies the publisher's normally-open clock contact that closes every minute.
IEC
HAN1B
Audible bell
A bell indication identifies an audible annunciation output in a control circuit.
IEC
HAN1Z
Audible buzzer
A buzzer indication identifies the specified audible signalling output.
IEC
HAN1S
Audible siren
A siren indication identifies an audible alarm output with the documented operating role.
IEC
HSV1
Solenoid valve actuator
This representation identifies the electrical actuator associated with a solenoid-operated valve.
IEC
HSV1Y1
Solenoid closing function for an open valve
This representation identifies the publisher's open-valve closing function associated with solenoid operation.
IEC
HSV1Y4
Electromagnetic brake actuator
This representation identifies an electromagnetic brake actuated through its documented electrical circuit.
IEC
HSV21
Solenoid-valve NO auxiliary contact
This form identifies a normally-open auxiliary contact associated with a solenoid valve.
IEC
HSV22
Solenoid-valve NC auxiliary contact
This form identifies a normally-closed auxiliary contact associated with a solenoid valve.
IEC
HPX1TS
Touch-sensitive switch
A touch-switch representation identifies operation by the documented touch-sensing mechanism.
IEC
HPX11TS
Touch-switch NO output
This form identifies a normally-open touch-switch output.
IEC
HPX12TS
Touch-switch NC output
This form identifies a normally-closed touch-switch output.
IEC
HPX11TS3
Three-wire touch-sensitive switch
This representation distinguishes a separately supplied three-wire touch-switch interface.
IEC
HPC11L
Latched pull-cord switch
This representation distinguishes a pull-cord actuator whose operated state is latched.
IEC
HFT11L
Latched foot-operated switch
This representation distinguishes a foot actuator with a retained operated state.
IEC
HPB11LSL
Latched lever-operated switch
This representation distinguishes a lever actuator with a maintained or latched operated state.
IEC