Interface relays connect computers and PLC logic devices to machines. But conventional block, modular terminal strips, and socket I/O relays are difficult to modify, and require hours of downtime for wiring and assembly if a relay fails or voltage requirements change.

Interfacers can be dedicated to ac, dc, or both. A built-in surge suppressor eliminates the need for additional components. The plug-in industrial grade relays use rugged bladed terminals that don't easily break or bend. This is in contrast to many relays on the market that rely on fragile, printed-circuit boards with easily bent or breakable pins. The relays have a single, universal-polarity relay socket that satisfies all voltage requirements from 12 Vdc to 230 Vac. Companies can now use a single socket for every interface in their plant rather than modular terminal strips that must have separate terminal strips and relays for every discrete voltage. Therefore, relay sockets need not be reinstalled and rewired every time application voltages or relay features change.

The new relays also simplify testing. Pushing a single button lets users momentarily activate the relay output. The button can also be lifted to lock the relay in the "on" position for further testing. Dual status indicators provide an LED pilot light and a mechanical flag to show relay output. And all socket wiring is done on a single level rather than the cumbersome multilevel approach in some stepped systems. An integrated clip prevents relays from vibrating out of the sockets.