Siemens SIRIUS Overload Relays

Siemens SIRIUS Overload Relays

If overload, phase imbalance or phase failure occur in the main circuit, then it doesn’t look good for the connected load – that is if you are not reliably protected. With SIRIUS overload relays.

3RU11 thermal overload relays up to 100 A with tripping CLASS 10

3RB20 solid-state overload relays up to 630 A with tripping CLASS 10 or CLASS 20

3RB21 solid-state overload relays up to 630 A where tripping CLASSES 5 to 30 can be set and a ground fault detection function that can be enabled

3RB22 solid-state overload relays up to 630 A where tripping CLASSES 5 to 30 can be set, a ground fault detection function can be enabled, a PTC sensor can be connected as well as monostable auxiliary contacts

3RB23 solid-state overload relays up to 630 A where tripping CLASSES 5 to 30 can be set, a ground fault detection functioncan be enabled, a PTC sensor can be connected and bistable auxiliary contacts

The overload relays are certified according to ATEX and thus suitable for motors with "increased safety" type of protection EEx e.