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ATS48 integral display is blank
ATS48 Altistart 48
Integral red LED display does not illuminate.
Follow the troubleshooting procedure below.
Is there control power?
Measure CL1 – CL2 for 90 - 270Vac.
Blown fuse? May indicate a shorted power supply on the power board or a problem with other devices (relays, pilot lights, etc) connected to the control power.
Measure DC Voltage between +24V – COM.
If 24VDC supply is OK (24VDC +/- 25%):
If 24VDC is not OK:
If J6 measures good, and the ribbon cable is properly installed but the display remains blank, replace the control board.
If another ATS48 is available, you could verify there are no other issues in the softstart by swapping control boards.
Note that the programmed parameters are stored in the control board, so changing or replacing the control board will require reprogramming.
Picture of the wide ribbon cable connection between power board and main control board.