"On Monday, 19 June 2006, at 1:15 pm EDT (17:15 UT), the Advanced Camera for Surveys (ACS) issued status buffer messages indicating that the +15V and +5V power supply voltages in the CCD Electronics Box (CEB) were above their high limits, causing the ACS to suspend. This event occurred in a period with no ACS commanding and outside the SAA. A dump of the relevant data showed that a total of 36 CEB items exceeded limits at the time of the event.

At this point, the ACS is in a safe configuration, and further analysis is ongoing. Preliminary reviews of the telemetry and technical details about possibly affected components of ACS have been carried out. However, the root cause for the ACS suspend is still unknown. Further analysis and testing revolves around low-voltage power supplies as well as analog to digital converters. Analysis of ACS images taken before the suspend event shows no anomalies of any kind."

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