Triac testing device for water heater - uses voltage supply, changeover device and indicator LEDs to direct triacs which are not blocking

摘要

The electrical test device contains a voltage supply (B; 21, 23) and a display circuit with forward and reverse driven light emitting diodes or LEDs (D1, D2) for each of several triacs (V1-V7) in the heater circuit. A first set of contacts (10-12) is connected to a pole of the voltage supply. Contacts (13-19) in a second set are connected via. the LEDs to the other supply pole. A changeover device (20) connects either the first contacts or the LEDs, either forward or reverse driven, to the supply voltage. If one of the triacs has a low impendence path in the blocking state then a current flows via this path and illuminates the associated LED. USE/ADVANTAGE - Enables simple detection during maintenance of triac which is not sufficiently blocking.