It is a small and compact unit based on latest electronic devices. It senses the current flowing through a totally electrically isolated circuit and energises the electromagnetic relay when the current crosses the set value. The current setting is done with a continuously adjustable knob over a linearly calibrated dial. It incorporates a built-in ON delay timer to avoid spurious trappings in case of transients with time adjustable from 1 to 10 seconds the help of a second knob over a calibrated dial. Two change over contacts of the delay are provided for the customer's usage. Three LED's (light emitting diodes) are provided on top of the unit to indicate voltage supply ON, relay ON status and Time ON.