Cause : External thermal relay operation comes when an overheat protection device such as a thermostat activates, the output of the converter is stopped. This function is available when "4" (OH signal) is set in any of Pr.3, Pr.4, and Pr.7 (Input terminal function selection). This protective function is not available in the initial status (OH signal is not assigned).

1. The converter output is shut off if terminals PC and SD are shorted when the OH signal is assigned to a terminal.
2. Check for the overheat of a thermostat or other similar peripheral devices.
3. Check that the value "4" (OH signal) is set to any of Pr.3, Pr.4, and Pr.7 (Input terminal function selection).
4. Check for a short circuit between terminals PC and SD.