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Control Assembly: Testing and Inspection






Control Panel Head Connector

Most of the terminal functions can be checked with the multipin connector attached to the control head. The connector must however, be removed to measure the resistance of the temperature sensors.


Terminals 10, 21, 22 and 3 form a multiplex electrical information connection between the programmer and control panel head. The voltage signals at these terminals are in the form of square waves and therefore cannot be accurately measured with normal shop equipment. If a problem is suspected, check the continuity of the wires between these terminals and the programmer connections.





Terminal Number & Function