Method for testing heating device using computer program of computer program product, involves indicating current difference between current immediately before start of switch-off of and current immediately after start of switch-on

摘要

The method involves subjecting a positive temperature coefficient (PTC) element (21) with a pulsed voltage. A current to the PTC element is measured. A current difference between a current immediately before the start of a switch-off of the pulsed voltage and a current immediately after the start of the switch-on of the pulsed voltage is indicated. An insufficient contact is detected between a heating element (1) and one of the PTC elements when the current difference exceeds a threshold current value.