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Reports until 16:06, Friday 20 January 2017
LHO VE (CDS)
david.barker@LIGO.ORG - posted 16:06, Friday 20 January 2017 - last comment - 00:19, Saturday 21 January 2017(33467)
WP6442, CP4 pump channels added to cell phone alarms, errors detected, channels removed from cell phone alarms

WP6442, alarm on positive LN2 level in CP4 pump

Chandra, Kyle, Gerardo, Dave

CP4 LN2 Pump Level channels were added to the cell phone text alert system ( H0:VAC-MY_CP4_LT250_PUMP_LEVEL_PCT,  H0:VAC-MY_CP4_LT250_PUMP_LEVEL_PCT_ERROR).

Unfortunately the ERROR channel was in Error this afternoon which caused many cell phone alerts. Trending this channel shows that over the past month it has been transitioning between Error and No Error states, which the majority of the time being in Error.

Until this channel's intermittent errors can be resolved, we cannot rely on this as a critical alarm. WP6442 work has been postponed until Monday.

Comments related to this report
david.barker@LIGO.ORG - 17:00, Friday 20 January 2017 (33468)
Link

here is a second  trend plot of the CP4 pump level and its Beckhoff error signal over the past 6 hours.

Images attached to this comment
patrick.thomas@LIGO.ORG - 00:19, Saturday 21 January 2017 (33473)
Link 

As Dave noted in his email to me, this is a 4-20 mA signal. From the attached trends it appears that the error signal is reflecting excursions out of this range.
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