The Chicago Pneumatic 1089920516 OEM overload relay is used primarily on the QRS25 and CPBG25 rotary screw compressors that operate on three phase power. This is an OEM part manufactured by Siemens and used by Chicago Pneumatic. This was also a common part used on a variety of Atlas Copco and Quincy air compressors.
The part number may be displayed in your manual as 1089 9205 16, 1089-9205-16, or 1089 9205 16.
There is a blue reset buttom. This can also be toggled between manual and automatic reset. When in manual mode the reset must by physically pushed in after the thermal trips.
The thermal overload relay will trip and cut power to the motor if the amperage spikes, preventing damage to the motor and the compressor. This typically needs to be replaced if the overload is shutting down the compressor prematurely before the amp draw reaches the trip set point.
This is an OEM part. Please contact us with your serial number for confirmation this item will work with your rotary screw air compressor.