Power house has introduced pt fuse failure relay series pptf-120. The relay is designed to help in detecting the fuse failure. Pt is a vital device in the over all control of the sub-station. To sense the fuse failure, input from each fuses two ends is connected to the relay. Till a load comes on the fuse, there is no potential voltage across the fuse and hence the relay is not energised, if any of the fuse fails, it develops potential voltage across the fuse terminal. Fuse failure is indicated by led on the front panel. This is sensed and the two contact relay is energized. The relay does not require any auxiliary supply as it is self-powered.
