Reports until 07:59, Wednesday 23 January 2013
X1 SUS
stuart.aston@LIGO.ORG - posted 07:59, Wednesday 23 January 2013 - last comment - 12:15, Wednesday 23 January 2013(5221)
SR3 (HLTS) tripping watchdogs 
Jeff B reported that the triple test stand watchdogs were being tripped when turning damping loops ON for the SR3 (HLTS) suspension.

This morning I've remotely logged-on to verify that the medm environment is correctly configured for a HLTS suspension (matrices & signs etc) i.e. the correct model is running and the correct environment has been BURT restored.

I also observed watchdogs tripping when enabling damping loops, specifically for the Pitch DOF.

Initially, I suspected some damping loop gain re-tuning maybe required, however the gain factor is consistent with other L1 & H1 HLTSs (-0.002).

Offsets were injected into each OSEM channel, T1, T2, T3, LF, RT, and SD, whilst monitoring the corresponding OSEM sensor readout in dataviewer. This indicated that there was a sign issues with T2 and T3 OSEMs. Temporarily changing the sign in the COIL OUTPUT FILTERS allowed damping loops to close, without tripping watchdogs. Therefore, I would recommend the assembly team double check T2 and T3 magnet polarity.
Comments related to this report
jeffrey.bartlett@LIGO.ORG - 12:15, Wednesday 23 January 2013 (5225)
Link 

   Checked the T2 and T3 BOSEMs. The magnets were OK. The B and C cables legs had been reversed. The cable problem has been corrected and the BOSEMs centered to 50% light. Offsets and gains values have also been corrected in MEDM and on the OSEM tracking spreadsheet. Successfully closed the damping loops without tripping the watchdogs. I will run the first set of TFs tonight.