A range of heavy duty electrical protection units designed to overcome inherent earth leakage or inrush currents. The unit combines a variable sensitivity and time delay (see VEF4/5 Data sheet) together with a triple pole MCCB to provide overcurrent (125A maximum) and short circuit protection (16KA).

The installation of this unit is recommended to achieve the optimum level of protection without the inconvenience of spurious tripping. Numerous applications throughout industry from construction sites, mines and quarries to the protection of stage lighting systems where thyristor spikes can trip conventional RCD's.