Event data stops being reported for one CCD/FEP combination and the delta overclock values are peculiar, large and negative for the first three output nodes and large and positive for the fourth output node.
It appears likely it could happen again.
Both of the following symptoms will be noticed:
deltaOverclock
values reported from these FEPs are large and negative for the first three output nodes and
large and positive for the fourth output node.Both of these symptoms can be observed from one of the PMON pages.
Most likely we will be notified by CXCDS Ops that data ceased prematurely for a single CCD for an observation. But there is a chance we can catch this anomaly in a realtime contact during a long observation. If yes, we have a SOP written to intervene if the observation with the anomaly is still in progress to dump diagnostic data.
If not, we need to: