Differential relay adjustment

Secure verification of Relays

Beside the differential adjustment of complete devices, we offer also the adjustment units for the relay adjustment. This adjustment is done in several steps. The first step is before the relay is magnetized to pulsate the pin of the relay. This should be done 30 to 60 times. If the relay is already magnetized, the device can be forced to keep open by a constant DC current.

A second step (if the relay is not magnetized) is to check the closing part of the relay. This is done by forcing a DC current so that the relay can be closed. Than the current will be decreased until it opens. This value gives information about the mechanical part.

The next step is to saturate the ferrit inside the relay. The saturation value shows the quality of this ferrit. The relay will now be adjusted similar to the device late, but at a lower value. The tripping value will not be measured by the current only. Also the voltage is measured at the same time. The tripping value is calculated in power (µVA). Therefor the relay needs to be contacted by Kelvin clamps ( 4-wire technology).

The tripping detection is done electrically. The pin doesn´t need to be observed by any sensor.

After the adjustment, the relay can be shocked up for transport.