Input & Output Interfaces


Input/output or I/O interface is the interaction between a central processing device, such as a PLC, and input and output devices. Inputs are the signals or data received by the processing system from a digital input device, such as a switch, relay or contactor, and analog inputs from various sensors indicating the status of physical parameters, such as temperature, pressure etc. Outputs are the signals or data sent from the processing system to digital output devices, such as an indicator, lamp, alarm, relay or contactor and analog output devices, such as motors, valves and Proportional Controllers etc.


Switch and Indicator Switches

A switch is an electrical component that can "make" or "break" an electrical circuit, interrupting the current or diverting it from one conductor to another. The mechanism of a switch removes or restores the conducting path in a circuit when it is operated. It may be operated manually, for example, a light switch or a keyboard button, may be operated by a moving object such as a door, or may be operated by some sensing element for pressure, temperature or flow.


Relays

A relay is an electrically operated switch. Many relays use an electromagnet to mechanically operate a switch, but other operating principles are also used, such as solid-state relays. Relays are used where it is necessary to control a circuit by a separate low-power signal, or where several circuits must be controlled by one signal.


Indicators (LED, lamps, beacon/emergency/stop lamps)

Emergency lamp, signal tower lights, indicator lights, andon lights, warning lights, industrial signal lights, tower lights, beacon and light towers are commonly used on equipment in industrial manufacturing and process control environments to provide visual indicators of a machine state or process event to machine operators, technicians, production managers and factory personnel.


Contactors

A contactor is an electrically controlled switch used for switching an electrical power circuit, similar to a relay except with higher current ratings and a few other differences. A contactor is typically controlled by a circuit which has a much lower power level than the switched circuit, such as a 24-volt coil electromagnet controlling a 220-volt motor switch.


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Contract pricing display is unavailable at the moment. Prices shown are standard retail prices, orders placed will have contract pricing applied when processed.

  Manufacturer Part No Order Code Manufacturer / Description
Availability Price For
Price
Quantity
RT424024
RT424024 - Power Relay, DPDT, 24 VDC, 8 A, RT2 Series, Through Hole, Non Latching

1629054

Power Relay, DPDT, 24 VDC, 8 A, RT2 Series, Through Hole, Non Latching

SCHRACK - TE CONNECTIVITY

RELAY, DPDT, 250VAC, 8A; Contact Configuration:DPDT; Coil Voltage:24VDC; Contact Current:8A; Product Range:RT2 Series; Relay Mounting:Through Hole; Coil Type:Non Latching; Contact Voltage VAC:250VAC; Relay Terminals:Solder; Contact Voltage VDC:-; Contact

  • 23,322 available for 3 - 4 business days delivery
  • 13,147 available for 4 - 5 business days delivery
+ Check Stock & Lead Times

  • 23,322 available for 3 - 4 business days delivery: (UK stock) Order before 7:35pm Mon – Fri. (Excluding National Holidays)
  • 13,147 available for 4 - 5 business days delivery: (US stock) Order before 6:00pm Mon – Fri. (Excluding National Holidays)

More stock available week commencing 15/02/21

Restricted Item
DM1-01P-30-3
DM1-01P-30-3 - Microswitch, Subminiature, Short Lever, SPDT, Solder, 1 A, 5 VDC

1735364

Microswitch, Subminiature, Short Lever, SPDT, Solder, 1 A, 5 VDC

MULTICOMP PRO

MICROSWITCH, SPDT, 1A, SHORT LEVER, 125V; Microswitch Type:Snap Action; Microswitch Actuator:Short Lever; Contact Configuration:SPDT; Switch Terminals:Solder; Contact Current Max:1A; Contact Voltage DC Nom:5VDC; Product Range:DM1 Series; Contact Voltage

  • 12,469 available for 1 - 2 business days delivery
  • 1,369,793 available for 3 - 4 business days delivery
+ Check Stock & Lead Times

  • 12,469 available for 1 - 2 business days delivery: (SG stock) Order before 4:30pm Mon – Fri. (Excluding National Holidays)
  • 1,369,793 available for 3 - 4 business days delivery: (UK stock) Order before 7:35pm Mon – Fri. (Excluding National Holidays)

More stock available week commencing 25/01/21

Restricted Item
DM1-02P-30-3
DM1-02P-30-3 - Microswitch, Snap Action, Lever, SPDT, Solder, 1 A, 5 VDC

1735365

Microswitch, Snap Action, Lever, SPDT, Solder, 1 A, 5 VDC

MULTICOMP PRO

MICROSWITCH, SPDT, 1A, SIM LEVER; Microswitch Type:Snap Action; Microswitch Actuator:Lever; Contact Configuration:SPDT; Switch Terminals:Solder; Contact Current Max:1A; Contact Voltage DC Nom:5VDC; Product Range:DM1 Series; Contact Voltage AC Nom:125VAC;

  • 10,033 available for 3 - 4 business days delivery
  • 105 available for 4 - 5 business days delivery
+ Check Stock & Lead Times

  • 10,033 available for 3 - 4 business days delivery: (UK stock) Order before 7:35pm Mon – Fri. (Excluding National Holidays)
  • 105 available for 4 - 5 business days delivery: (US stock) Order before 6:00pm Mon – Fri. (Excluding National Holidays)

More stock available week commencing 25/01/21

Restricted Item
RTE24005
RTE24005 - General Purpose Relay, RT2 Series, Power, Non Latching, DPDT, 5 VDC, 8 A

1703727

General Purpose Relay, RT2 Series, Power, Non Latching, DPDT, 5 VDC, 8 A

POTTER&BRUMFIELD - TE CONNECTIVITY

RELAY, DPDT, 250VAC, 5VDC, 3A; Contact Configuration:DPDT; Coil Voltage:5VDC; Contact Current:8A; Product Range:RT2 Series; Relay Mounting:Through Hole; Coil Type:Non Latching; Contact Voltage VAC:250VAC; Relay Terminals:Solder; Contact Voltage VDC:24VD

  • 6,890 available for 3 - 4 business days delivery
  • 2,164 available for 4 - 5 business days delivery
+ Check Stock & Lead Times

  • 6,890 available for 3 - 4 business days delivery: (UK stock) Order before 7:35pm Mon – Fri. (Excluding National Holidays)
  • 2,164 available for 4 - 5 business days delivery: (US stock) Order before 6:00pm Mon – Fri. (Excluding National Holidays)

  • 500 more will be available on 1/11/20
  • More stock available week commencing 7/12/20

    Restricted Item
    RTD14012
    RTD14012 - General Purpose Relay, Power PCB Relay RT1 Series, Power, Non Latching, SPDT, 12 VDC, 16 A

    1175016

    General Purpose Relay, Power PCB Relay RT1 Series, Power, Non Latching, SPDT, 12 VDC, 16 A

    TE CONNECTIVITY

    RELAY, SPDT, 250VAC, 16A; Contact Configuration:SPDT; Coil Voltage:12VDC; Contact Current:16A; Product Range:RT1 Series; Relay Mounting:Through Hole; Coil Type:DC; Contact Voltage VAC:250VAC; Relay Terminals:Solder; Contact Voltage VDC:-; Contact Materia

    • 10,670 available for 3 - 4 business days delivery
    + Check Stock & Lead Times

    • 10,670 available for 3 - 4 business days delivery: (UK stock) Order before 7:35pm Mon – Fri. (Excluding National Holidays)

    More stock available week commencing 23/11/20

    Restricted Item
    M140T01-AE0507A
    M140T01-AE0507A - Microswitch, Snap Action, Long Lever, SPDT, Solder, 5 A

    1735352

    Microswitch, Snap Action, Long Lever, SPDT, Solder, 5 A

    MULTICOMP PRO

    MICROSWITCH, SPDT, 5A, LONG LEVER; Microswitch Type:Snap Action; Microswitch Actuator:Long Lever; Contact Configuration:SPDT; Switch Terminals:Solder; Contact Current Max:5A; Contact Voltage DC Nom:-; Product Range:M140T01 Series; Contact Voltage AC Nom:

    • 1,094 available for 3 - 4 business days delivery
    + Check Stock & Lead Times

    • 1,094 available for 3 - 4 business days delivery: (UK stock) Order before 7:35pm Mon – Fri. (Excluding National Holidays)

  • 3,000 more will be available on 28/12/20
  • More stock available week commencing 25/01/21

    Restricted Item
    RT314615
    RT314615 - General Purpose Relay, Power PCB Relay RT1 Series, Power, Non Latching, SPDT, 115 VAC, 16 A

    1629048

    General Purpose Relay, Power PCB Relay RT1 Series, Power, Non Latching, SPDT, 115 VAC, 16 A

    SCHRACK - TE CONNECTIVITY

    RELAY, SPDT, 250VAC, 16A; Contact Configuration:SPDT; Coil Voltage:115VAC; Contact Current:16A; Product Range:RT1 Series; Relay Mounting:Through Hole; Coil Type:Non Latching; Contact Voltage VAC:250VAC; Relay Terminals:Solder; Contact Voltage VDC:-; Cont

    • 19,477 available for 3 - 4 business days delivery
    + Check Stock & Lead Times

    • 19,477 available for 3 - 4 business days delivery: (UK stock) Order before 7:35pm Mon – Fri. (Excluding National Holidays)

    More stock available week commencing 4/01/21

    Restricted Item
    V7-1V19E9
    V7-1V19E9 - Microswitch, Miniature, Pin Plunger, SPDT, Quick Connect, 21 A

    1796579

    Microswitch, Miniature, Pin Plunger, SPDT, Quick Connect, 21 A

    HONEYWELL

    MICROSWITCH, PIN, SPDT, 277VAC, 21A; Microswitch Type:Miniature; Microswitch Actuator:Pin Plunger; Contact Configuration:SPDT; Switch Terminals:Quick Connect; Contact Current Max:21A; Contact Voltage DC Nom:-; Product Range:V7 Series; Contact Voltage AC

    • 798 available for 3 - 4 business days delivery
    • 11,754 available for 4 - 5 business days delivery
    + Check Stock & Lead Times

    • 798 available for 3 - 4 business days delivery: (UK stock) Order before 7:35pm Mon – Fri. (Excluding National Holidays)
    • 11,754 available for 4 - 5 business days delivery: (US stock) Order before 6:00pm Mon – Fri. (Excluding National Holidays)

    More stock available week commencing 9/11/20

    Restricted Item
    SSM-001
    SSM-001 - Microswitch, Snap Action, Lever, SPDT, Solder, 500 mA, 30 VDC

    1735368

    Microswitch, Snap Action, Lever, SPDT, Solder, 500 mA, 30 VDC

    MULTICOMP PRO

    MICROSWITCH, SPDT, 0.5A, PLASTIC LEVER; Microswitch Type:Snap Action; Microswitch Actuator:Lever; Contact Configuration:SPDT; Switch Terminals:Solder; Contact Current Max:500mA; Contact Voltage DC Nom:30VDC; Product Range:-; Contact Voltage AC Nom:-; Ope

    • 18,700 available for 3 - 4 business days delivery
    + Check Stock & Lead Times

    • 18,700 available for 3 - 4 business days delivery: (UK stock) Order before 7:35pm Mon – Fri. (Excluding National Holidays)

    More stock available week commencing 18/01/21

    Restricted Item