Reports until 21:54, Saturday 31 May 2014
H1 TCS
thomas.vo@LIGO.ORG - posted 21:54, Saturday 31 May 2014 - last comment - 23:35, Sunday 01 June 2014(12162)
TCS Ring Heater Test 
D. Hosken, G. Grabeel, T. Vo

We were able to fix the ring heater chassis EtherCAT wiring by referencing the drawings.  We initially turned both ITM ring heaters to 30 Watts at 6:46 PM PT but it seems as though the maximum power that the drivers can put out is ~15-16 Watts so we changed the script that Greg wrote to run the power at 13.5 Watts during the high power portion and .5 Watts in the low power portion.  I'll come in tomorrow morning to run some trends and take some measurements.  John verified in the first hour that there were no spikes in pressure.
Comments related to this report
thomas.vo@LIGO.ORG - 13:58, Sunday 01 June 2014 (12164)
Link 

Here's the past 17 hour trends, there doesn't seem to be much correlation between pressure and ring heater cycling. The test is going to run for about another 5.5 hours or so.

Also, I've plotted one cycle at 17:17 UTC and you can see the voltage rise to a steady state in about 30 minutes or so as we would expect, which means that the temperature of ring heater in question is in fact getting hotter which changes the resistivity and the ring heater driver is reacting to that change.  The current output is noisier and the X_UpperCurrent doesn't seem to follow this trend and I'm not sure why.
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aidan.brooks@LIGO.ORG - 18:43, Sunday 01 June 2014 (12165)
Link 

The RH driver is a current source. There's an internal servo that holds the drive current steady - hence it doesn't change as the RH resistivity changes.
thomas.vo@LIGO.ORG - 23:35, Sunday 01 June 2014 (12166)
Link 

Thanks Aidan. We've finished with the test, both ITM RHs are now off.