KRM72x - PHASE FAILURE / SEQUENCE RELAY
Phase failure
Phase Imbalance
Incorrect Phase Sequence
Description
KRM72x monitors three phase AC supplies for incorrect phase sequence, phase failure and phase imbalance on systems up to 500V.
Operation
A sensitivity adjustment on the top of the unit allows adjustment up to 50% of the phase to phase voltage. The minimum level is selected to avoid any nuisance tripping due to normal variations in voltages.
A factory set delay of approximately two seconds prevents tripping due to transients. The unit is factory set for 50Hz or 60Hz. It is available as a 50/60Hz variation with associated loss of sensitivity.