General-Purpose Relays

A general-purpose relay is a socketed electromechanical relay, not dedicated to a single application, whose changeover contacts change position when voltage is applied to its coil. It is used in control panels for signal multiplication, as an interposing relay between a PLC output and a contactor coil, and for direct switching of small loads. The category includes Schneider Electric RXM miniature, RXG and RSB interface relays, Finder 55, 56 and 60 series relays, ABB CR-MX and CR-U socketed relays, and Isıso relays; 2, 3 and 4 CO contact arrangements, contact currents such as 7 A, 10 A and 12 A, and coil voltages such as 12 V DC, 24 V DC, 110 V DC and 230 V AC are listed. Select the coil voltage according to the control voltage, the number of contacts according to the circuit diagram, the contact current according to the current and type of the load (resistive, inductive, AC or DC), and the pin layout according to the socket series you will use. The relay and socket are mostly separate products; the sockets are in the Relay Sockets and Accessories category. A general-purpose relay does not protect a motor against overload; it is not a substitute for a thermal overload relay used with a contactor.

Products

How to choose General-Purpose Relays

A general-purpose relay is a socketed electromechanical relay, not dedicated to a single application, whose changeover contacts change position when voltage is applied to its coil. It is used in control panels for signal multiplication, as an interposing relay between a PLC output and a contactor coil, and for direct switching of small loads.

  • Separate sensing, motion control, logic processing and operator interface requirements.
  • Select signal type, supply voltage, communication protocol and I/O count for the machine network.
  • Verify housing size, sensing distance and PNP/NPN output polarity against the PLC input card.

Frequently asked questions

What is General-Purpose Relays and where is it used?

A general-purpose relay is a socketed electromechanical relay, not dedicated to a single application, whose changeover contacts change position when voltage is applied to its coil. It is used in control panels for signal multiplication, as an interposing relay between a PLC output and a contactor coil, and for direct switching of small loads.

What should I compare when choosing General-Purpose Relays?

Select the coil voltage according to the control voltage, the number of contacts according to the circuit diagram, the contact current according to the current and type of the load (resistive, inductive, AC or DC), and the pin layout according to the socket series you will use.

Where can I find technical details for General-Purpose Relays products?

A general-purpose relay is a socketed electromechanical relay, not dedicated to a single application, whose changeover contacts change position when voltage is applied to its coil.

General-Purpose Relays Selection Guide: Technical Criteria and Engineering Practice