Ground loop checks for SUS have been completed for the following HAM's:
HAM2, HAM3, HAM4, HAM5, and HAM6.
Multiple shorts to ground chamber were found and addressed. Many cables required the in-vacuum cables to be disconnected at the flange and re-seated. See alog 12528 for similar issues of four screws touching the feed-thru if not recessed completely.
HAM 3 gave us the most difficulties. In-chamber shorts were found at one of the table brackets. We also suspect air-side cables SUS-3 and SUS-26 to be faulty. To convince ourselves we had no grounding shorts in-chamber we disconnected the following air-side cables and tested directly at the air-side feed-thru: cables SUS-3, SUS-2, SUS-25, and SUS-26.
Same was seen on HAM5 for cable SUS-20.
Testing of OFI and SQZ ZM(tip-tilts) all passed.
TCS temperature sensor - Read about 110 ohms on pins 1/2 and 14/15 which does not agree to drawing. According to D1102257, two sets of RTD's should be seen on pins 2/3 and 14/15 and on pins 12/13 and 24/25.
Shorts were also found in the BSC chambers that still need to be looked at:
ITMX - SUS-42, SUS-57
ITMY - SUS-9, SUS-17
BS - SUS-81, SUS-82
Please note that moving cables in-chamber can produce shorts. Please use caution when doing final closeout activities.
Translating which BSC SUS cables correspond to which, from D1100022, ITMX - SUS-42 = M0 LF RT, R0 LF RT OSEMs' signal chain, from vacuum flange to field sat amp SUS-57 = L2/PUM UL LL UR LR OSEMs' signal chain, from vacuum flange to field sat amp ITMY - SUS-9 = Reaction Chain's (R0) F1 F2 F3 SD OSEMs' signal chain, from the vacuum flange to the field sat amp SUS-17 = L2/PUM UL LL UR LR OSEMs' signal chain, from vacuum flange to field sat amp BS - SUS-81 = M1 F1 F2 F3 LF OSEMs' signal chain, from vacuum flange to field sat amp SUS-82 = M1 RT SD OSEMs' signal chain, from vacuum flange to sat amp