5.5-8Amp Siemens Sirius 3RU112 Bimetallic Class 10 Overload Relay with Screw Terminals

3RU112 overload relays belong to the new generation of SIRIUS 3R control products. The 3RU112 overload relays replace the highly successful 3UA5 and 3UA7 devices. Outstanding features of the new overload relays include long term stability and long service life. The overload relays are optimally matched, both electrically and mechanically, to the 3RT10 contactors. They can also be mounted as a single unit with the use of a separate mounting bracket. 3RU112 overload relays cannot be mounted onto 3TF contactors.

Application:
3RU112 overload relays provide overload protection for three-phase inductive motors with rated currents of up to 100A (75HP, AC-3, 480V). They are used in conjunction with 3RT10 contactors to form motor starters.

Ambient conditions
Thanks to the newly integrated bimetal and continuous temperature compensation, these devices can be used without derating at an ambient temperature of up to 60°C (140°F). Use up to 70°C (158°F) is possible with derating. (See Siemens Industrial Control Products Catalog - CPPC-06000).

Auxiliary contacts
The overload relays are equipped with a NC contact for de-energizing the contactor and a NO contact for signalling an overload trip. The breaking capacity of the switching contacts is very high so that the contactor coils can be switched directly.

Trip class
The 3RU11 overload relays are designed in accordance with trip class 10, i.e. trips in less than 10 seconds at 6 times the trip current setting (FLA).