U-EK230E

Thermistor motor protection device for effective protection of EX fans

  • ATEX approved 

  • Manual reset 

  • Maintenance free 

  • Casing available 


Effective motor protection

The U-EK 230E is a thermistor motor protection device that provides effective protection for Ex fans that have integrated PTC (Positive Temperature Coefficient) protective circuits.

Maintenance-free

The devices are maintenance free and any repairs must be carried out by the manufacturer. 


Optional casing

For added protection, the U-EK 230E is available with an optional casing as an accessory. 


The U-EK 230E is a thermistor motor protection device which is intended for use in conjunction with a contactor for the protection of the Ex fans with integrated PTC (Positive Temperature Coefficient) protective circuits. It is an electronic unit that is designed for snap fitting onto a 35 mm instrument rail (DIN rail). Fan motors have six series-connected thermistors, two per phase winding, whose resistance is determined by the motor temperature. If the motor temperature exceeds the permitted limit the resistance rises sharply and the motor protector is triggered. Once this has been triggered a warning light is illuminated. 

In case of failure, the relay switches off the contactor/circuit breaker and so prevents an overheating of the isolation system and/or the surface temperature. The protective function of the equipment is guaranteed only if wiring is done directly into the control circuit of the motor/machine in accordance with the connection diagram.