R1S5 SL2 BurnIn

Date	Time (24h)	Guard (V)	Sense (V)	Field (V)	Sense ([math]\mu[/math]A)	Field ([math]\mu[/math]A)	comments
05/28/13	14:08	100	100	-100	0.02	0.00	Confirmed with initial setting of 30/40/50V that there are no crossed connections between wire types and that voltage supply is connected correctly.
05/28/13	16:34	536	1500	-750	45.5	45.5	Someone upped the voltage to full the full operating level without recording it. This is the current reading right now.
05/28/13	17:56	536	1500	-750	41.5	41.6
05/29/13	07:56	536	1500	-750	22.5	22.6
05/29/13	15:02	536	1500	-750	17.9	18.0
05/29/13	18:07	536	1500	-750	16.7	16.8
05/30/13	07:55	536	1500	-750	10.6	10.7
05/30/13	12:51	536	1500	-750	9.5	9.6
05/30/13	17:23	536	1500	-750	8.7	8.8
06/03/13	08:23	536	1500	-750	1.7	1.8
06/04/13	07:42	536	1500	-750	1.4	1.5
06/05/13	12:01	536	1500	-750	1.8	1.9	had to turn off HV to organize cables
06/05/13	17:56	536	1500	-750	1.8	1.9
06/06/13	07:56	536	1500	-750	1.8	1.9	seem to be stuck at this current draw?
06/10/13	17:29	536	1500	-750	1.5	1.6	I think we ran out of gas on the weekend, the windows were deflated a bit but now they deflected outward
06/11/13	07:50	536	1500	-750	3.2	3.3	current doubles? Humidity dropped from 40 to 25%.
06/12/13	13:39	536	1500	-750	3.6	3.7	Humidity rose from 25 to 40%.
06/13/13	11:00	536	1500	-750	4.5	4.6	Humidity is 40 +/- 5 %.
06/14/13	08:56	536	1500	-750	3.5	3.6
06/17/13	07:58	536	1500	-750	3.6	3.7
06/24/13	08:37	536	1500	-750	4.5	4.6	turned off HV since 6/17/13 but continued flowing gas
06/24/13	10:05	536	1500	-750	5.14	5.24
06/24/13	12:46	536	1500	-750	5.10	4.99
06/25/13	10:36	536	1500	-750	4.7	4.7
07/12/13	11:45	536	1500	-750	1.0	1.1	HV was turned back on to check current levels, I will leave it on over the weekend
07/13/13	9:13	536	1500	-750	0.76	0.84
07/14/13	9:04	536	1500	-750	0.70	0.76
07/14/13	20:49	536	1500	-750	0.74	0.81
07/15/13	07:23	536	1500	-750	0.70	0.78	There is a guard current when I turned on the power supply for burning, I did not increase the voltage to check if this is ok. Also I checked sector one it is working, i saw signal in all the channels that are connected to the "Dawn" VME. I debugged sector5 's board that has a guard current, none of the boots is responsible for the for the guard curent, as all of them are out of the board, the guard current is still there, the only way to get rid of it is to separate the guard's jumpers from any side of the board. I checked the resistors of the board, they all good.
11/24/13	07:23	536	1500	-750	0.70	0.80	guard current is zero

Why is the current increasing?

is the current going to ground ?

Try raising the sense to 1750 and lowering the field to 500 (same voltage difference), and see if the sense current still equals the field current - want to know if the current is inside the chamber from wire to wire or if it's a current to ground, for example ...

If current is from field to sense:

if it is current from field to sense the current should increase exponentially with voltage, doubling with 100V increase; i.e. 2250 -> 2350. You could check to see if this is the case. If so, you could then try to locate where the problem is: which wire(s) are responsible?

Increasing Sense

Date	Time (24h)	Guard (V)	Sense (V)	Field (V)	Sense ([math]\mu[/math]A)	Field ([math]\mu[/math]A)	comments
06/17/13	12:20	536	1510	-750	8	8.1
06/17/13	12:16	536	1520	-750	10.7	10.8
06/17/13	12:34	536	1530	-750	22.3	22.4
06/17/13	12:43	536	1540	-750	37.3	37.4
06/17/13	15:53	536	1540	-750	45.2	45.3
06/17/13	15:55	536	1550	-750	54.9	55.1

Lower the field to -500 V

Date	Time (24h)	Guard (V)	Sense (V)	Field (V)	Sense ([math]\mu[/math]A)	Field ([math]\mu[/math]A)	comments
06/17/13	15:55	536	1550	-750	54.9	55.1
06/17/13	15:58	536	1550	-740	45.9	46.1
06/17/13	15:59	536	1550	-730	37.6	37.9
06/17/13	14:00	536	1550	-710	24.2	24.3
06/17/13	14:02	536	1550	-690	13.9	14.0
06/17/13	14:03	536	1550	-650	3.8	3.9
06/17/13	14:04	536	1550	-600	1.33	1.41
06/17/13	14:05	536	1550	-550	0.88	0.97
06/17/13	14:06	536	1550	-500	0.66	0.74

Increase sense when Field is at -500 V

Date	Time (24h)	Guard (V)	Sense (V)	Field (V)	Sense ([math]\mu[/math]A)	Field ([math]\mu[/math]A)	comments
06/17/13	14:06	536	1550	-500	0.66	0.74
06/17/13	14:10	536	1650	-500	1.5	1.6
06/17/13	14:13	536	1750	-500	16.2	16.3

SL2 current draw search

Date	Time (24h)	Guard (V)	Sense (V)	Field (V)	Sense ([math]\mu[/math]A)	Field ([math]\mu[/math]A)	comments
06/18/13	08:57	536	1550	-550	0.59	0.69	no voltage to HVB1
06/18/13	09:00	536	1550	-500	0.46	0.55	no voltage to HVB1
06/18/13	09:12	536	1650	-500	1.1	1.2	no voltage to HVB1
06/18/13	09:17	536	1750	-500	9.5	9.6	no voltage to HVB1, less current measured
06/18/13	10:31	536	1550	-500	0.32	0.42	no voltage to HVB1 and HVB2
06/18/13	10:40	536	1650	-500	1.0	1.1	no voltage to HVB1 and HVB2
06/18/13	10:45	536	1750	-500	8.8	8.9	no voltage to HVB1 and HVB2
06/18/13	11:07	536	1550	-500	0.32	0.42	no voltage to HVB1 and HVB3
06/18/13	11:11	536	1650	-500	1.0	1.1	no voltage to HVB1 and HVB3
06/18/13	11:16	536	1750	-500	6.8	6.9	no voltage to HVB1 and HVB3
06/18/13	11:31	536	1550	-500	0.34	0.43	no voltage to HVB1,HVB3,and HVB4
06/18/13	11:34	536	1650	-500	0.82	0.92	no voltage to HVB1,HVB3,and HVB4
06/18/13	11:38	536	1750	-500	5.0	5.1	no voltage to HVB1,HVB3,and HVB4 negligible effect
06/18/13	12:12	536	1550	-500	0.34	0.42	no voltage to HVB1,HVB3,and HVB5
06/18/13	12:15	536	1650	-500	0.89	0.97	no voltage to HVB1,HVB3,and HVB5
06/18/13	12:19	536	1750	-500	4.9	5.0	no voltage to HVB1,HVB3,and HVB5 negligible effect
06/18/13	14:08	536	1550	-500	0.0	0.055	no voltage to HVB1,HVB3,and HVB6
06/18/13	14:24	536	1650	-500	0.2	0.27	no voltage to HVB1,HVB3,and HVB6
06/18/13	14:30	536	1750	-500	4.5	4.6	no voltage to HVB1,HVB3,and HVB6
06/18/13	14.50	536	1550	-500	0.335	0.420	no voltage to HVB1,HVB3,and HVB7
06/18/13	14:53	536	1650	-500	0.965	1.035	no voltage to HVB1,HVB3,and HVB7
06/18/13	15:00	536	1750	-500	5.2	5.3	no voltage to HVB1,HVB3,and HVB7
06/26/13	17:37	536	1500	-750	4.6	4.3	Switched to SL2 Kraken HV after burning in SL1 HVB1 with Octopus. SL1 HVB1 burned down to about 1 microamp over ~24 hrs after starting at a high of 4 microamps. When setting up HVB1 for burn-in, noticed a grounding strap attached to the board that caused high guard current even at 30V. Removed the strap and this problem was resolved, burn-in proceeded normally. This is the reading on SL2 + Kraken immediately after reaching 1500V on sense.
06/26/13	17:41	536	1500	-750	5.7	5.3	Guard current is at 0.295 microamps. Normally is below a level detectable by this HV supply (0.000).
06/26/13	17:55	536	1500	-750	5.3	5.0	Noticed several of the mounting screws that go into the chamber's metal frame for both STBs and HVBs on SL2 were not torqued to 13 in. lbs / some were obviously loose. Turned off HV and torqued down all mounting screws. Some do not appear flush against STB/HVB surface, but most are flush. Turned back on HV. Guard current is still 0.280 microamps. Torquing screws didn't fix it.
06/27/13	17:25	536	1500	-750	2.8	2.7	Guard current is down to 0.045

Sense Field difference constant

Change sense and field wire voltage but keep the difference 2350 Volts. Record currents over a time interval of minutes. Don't wait long.