Rapid turn-on, slow drop-out control arrangement

摘要

An electrical equipment controller is provided with a delayed turn-off capability. A thermostat is in series with a control relay. The thermostat is further in parallel with the series combination of a relay latch contact and a first positive temperature coefficient (PTC) device. A second PTC device is connected in parallel with the control relay. The arrangement of first and second PTC devices provides a predeterminable drop-out relay including compensation for ambient temperature changes.