WP 12953

I was notified of a buzzing/whistling sound coming from the CER mezzanine. The HV power supply for the OMC PZT was found with audible alarm on and LCD screen not displaying correctly. Power supply was power cycled. Unit tripped immediately. With unit off, the field cabling going to LVEA was disconnected. Unit tripped when powered on. Unit was replaced with spare.

F. Clara, R. McCarthy, M. Pirello