david.barker@LIGO.ORG - posted 11:25, Monday 19 June 2017 - last comment - 08:00, Tuesday 20 June 2017(36996)
investigation into recent timing alarms
In the past week we have had two timing alarms:
| Monday 6/12 01:19 UTC [Sunday 6/11 18:19 PDT) | EY GPS |
| Saturday 6/17 23:15 - 23:24 UTC (16:15 - 16:24 PDT) | MSR Master GPS |
The first was a short (one minute) alarm from EY GPS (CNS-II). I trended all the EPICS channels on this system and only found that the Dilution of Precision (DOP) and the Receiver mode channels showed any variation at this time (number of satellites locked did not change). Does this mean it is a real or bogus error?
The second was a longer alarm (9 minutes) with the MSR master's GPS receiver (I think the internal one). The only channels in alarm were "GPS locked", the the MSR comparator channel-01 (MFO GPS). This would suggest a real problem with the Master's GPS receiver?
Time to pass this over to the timing group for further investigation (Daniel, Zsuzsanna, Stefan?)
These are error messages seem real, but are non critical. The internal GPS is only used to set the GPS date/time.