Reports until 10:50, Monday 23 February 2015
H1 SEI
hugh.radkins@LIGO.ORG - posted 10:50, Monday 23 February 2015 (16862)
SEI Saturations: Where. Why?

After clearing all the SEI Overflows on the GDS_TP medms Friday, this morning some have and some don't report new overflows.  Where do this come from?

Okay--No Overflows reported over the weekend on:

HEPI: HAMs 2, 4 & 5, BSCs ITMY, ITMX, BS, ETMY; ISIs: HAMs 2, 4, 5, ITMY, ITMX, ETMY.

So that leaves Overflows did occur on:

HPIs HAMs 3, 6, & BSC ETMX and ISIs HAM3, HAM6, BS, & ETMX.

Okay so there is almost a complete pattern here.  The BS is the only platform that had overflows on the ISI but not on the HEPI.

So for the overflows, on the ISIs, HAM3, HAM6, ETMX and the BS have overflows on the GS13s, the L4Cs, and on the DACs.

For HEPI there are overflows on the ETMX DAC; but, strangely, while the GDS-TP Overflows (e.g.:H1:FEC-55_ACCUM_OVERFLOW) have non-zero numbers, non of the ADC or DAC accumulators show any totals on the HAM3 or HAM6 (e.g.:H1:FEC55_ADC_OVERFLOW_ACC_2_9)...

See the attached for the inconsistant circled numbers: there are overflow totals on the overflow but non on the ADCs or DAC to support where they originate.

So next, I'll try to put a reason for the Overflows: maay an earthquake or a trip (although I don't believe we had any trips.  HAM6 with the Fast Shutter may be the only platform with a valid reason for overflows.  And, why does the HAM3 and HAM6 HEPI overflows don't show from where they came.

Images attached to this report