Where the expansion units for 3SK1 safety relays are concerned, a distinction is made between input and output expansions:

4RO output extension

Is the number of outputs on the basic unit insufficient for your application? If so, expand the basic unit with the 4RO contact expansion. This expansion features 4 relay outputs for switching currents up to 4 A.

3RO output expansion

Do you need special switching characteristics? Then opt for the contact expansion with three power relay outputs for switching high currents up to 10 A.

3SK1220 input expansion

Do you need more than one sensor? Then save yourself basic units in the Advanced device series. Instead of additional basic units, only one 3SK1220 input expansion is required.

3SK1230 power supply

The 24 V power supply supplies up to six components with voltage – whether basic units, input or output expansions. It covers all conventional global control voltages from 110 to 240 V AC/DC. This facilitates the safety relays' international applicability.