The helium pressure test on TM3 HS water line with new Ta target is finished at CS. The circuit is leak tight.. No any response on LD. See pictures.

This morning, The helium pressure leak check on TM4 Ta(-) is done after TM4 finished conditioning yesterday.  LD base LR:8.0XE-9 atm.cc/sec, base pressure: 0.0XE-4 torr. Applied 70 psi helium to TM4 TA(-) water line. The LR slowly climbed to 2.2XE-7 atm.cc/sec, and stopped there. Waited for 5 minutes and change at 2.2 X E-7 atm.cc/sec.

Helium pressurize on TM2 HS line at TCS is done.    Base LR is 0.0X E-9 atm.cc/sec.  70 psi helium 3 minutes.   No response.   Also, The TCS vacuum pumping down over night is good. 

LD 0.0 Xe-9 atm.cc/sec , 70 psi helium 3 minutes.  No leak.

Connected leak detector to TM1 and CS vacuum system. The vacuum readings on TM1 and CS:PNG1 1.3 xE-6 Torr, IG1 4.7xE-7torr, IG4(diagnostic box)1.5xE-6 Torr. Leak detector base pressure:0.0xE-4 torr, base leak rate: 0.0xE-9 atm.cc/sec. Applied 80 psi helium to heat shield circuit for 5 mins . There is no response on leak detector. The heat shield circuit is leak tight.

 Today Chad entered the south hot cell on work permit 2013-08-29-3 to repair the leaking heat shield line. The heat shield line was removed from the module and the surfaces cleaned. New C seals and spring were inserted and the line re-attached. During this time Chad also installed the new vacuum gauge. Grant took video of this work and Keith some pictures. The video and pictures can be found on the M: drive (groups) in the RH folder. The total time taken was ~ 25 minutes. The line was then pumped on and the block was sprayed with helium. The pressure and leak rate started at 0.0 x 10^-4 Torr and 4.0 x 10^-8 atm*cc/Sec. When the helium tank was opened there was an immediate response with the leak rate climbing to 2.7 x 10^-7 atm*cc/Sec. It then stabilized at 2.0 x 10^-7 atm*cc/Sec and was sprayed with helium. Response time was ~2 seconds the leak rate climbed to ~2.3 x 10^-5 atm*cc/Sec the pressure also increased to ~3.0 x 10^-3. The leak detector cart was left attached for another 1.5 hours but still was not able to stabilize in the 10^-9atm*cc/Sec range. 

Bevan Moss wrote:

Today Chad entered the south hot cell on work permit 2013-08-29-3 to repair the leaking heat shield line. The heat shield line was removed from the module and the surfaces cleaned. New C seals and spring were inserted and the line re-attached. During this time Chad also installed the new vacuum gauge. Grant took video of this work and Keith some pictures. The video and pictures can be found on the M: drive (groups) in the RH folder. The total time taken was ~ 25 minutes. The line was then pumped on and the block was sprayed with helium. The pressure and leak rate started at 0.0 x 10^-4 Torr and 4.0 x 10^-8 atm*cc/Sec. When the helium tank was opened there was an immediate response with the leak rate climbing to 2.7 x 10^-7 atm*cc/Sec. It then stabilized at 2.0 x 10^-7 atm*cc/Sec and was sprayed with helium. Response time was ~2 seconds the leak rate climbed to ~2.3 x 10^-5 atm*cc/Sec the pressure also increased to ~3.0 x 10^-3. The leak detector cart was left attached for another 1.5 hours but still was not able to stabilize in the 10^-9atm*cc/Sec range.

 Also of note is that Chad received a full days dose and that when the plastic was surveyed there were ~150 counts found on it.

Bevan Moss wrote:

Bevan Moss wrote:  Today Chad entered the south hot cell on work permit 2013-08-29-3 to repair the leaking heat shield line. The heat shield line was removed from the module and the surfaces cleaned. New C seals and spring were inserted and the line re-attached. During this time Chad also installed the new vacuum gauge. Grant took video of this work and Keith some pictures. The video and pictures can be found on the M: drive (groups) in the RH folder. The total time taken was ~ 25 minutes. The line was then pumped on and the block was sprayed with helium. The pressure and leak rate started at 0.0 x 10^-4 Torr and 4.0 x 10^-8 atm*cc/Sec. When the helium tank was opened there was an immediate response with the leak rate climbing to 2.7 x 10^-7 atm*cc/Sec. It then stabilized at 2.0 x 10^-7 atm*cc/Sec and was sprayed with helium. Response time was ~2 seconds the leak rate climbed to ~2.3 x 10^-5 atm*cc/Sec the pressure also increased to ~3.0 x 10^-3. The leak detector cart was left attached for another 1.5 hours but still was not able to stabilize in the 10^-9atm*cc/Sec range.   Also of note is that Chad received a full days dose and that when the plastic was surveyed there were ~150 counts found on it.

Today Chad entered hot cell again and removed the HS module side and Junction Block Wiring Harness (module side). In addition to this he blanked off the module side HS line. It took Chad 16 minutes to perform these tasks and he received a dose of 0.20 mSv bringing his total to 0.84 over the last 2 days. After exiting the hot cell Chad completed a leak check on the module side. The line pumped down to the limits of the leak testing cart 0.0x10^-4 Torr and 0.0x10^-9 atm*cc/sec and there was no response. A video of Chad in the hot cell can be found in:

M:\remote handling\Photos\2013\2013_tm3_source_tray_refurb

This afternoon was spent surveying the anteroom and receiving teaching from Chad as to how to be a hot cell operator. There was little in the way of contamination ~150 counts near the HC door and ~50 counts on the surrounding floor. The wiring harness has a field of 900 uSv/hr but is suspected most of that is coming from the aluminum steerer bracket. 

The heat shield circuit was pressurized with air (15-20 psi) and snoop applied to the water block joint and brazes. Bubbles formed at the joint between the two water blocks indicating that the leak is a c seal problem. Pictures attached but also on docushare Collection-11285.

chad fisher wrote:

The heat shield circuit was pressurized with air (15-20 psi) and snoop applied to the water block joint and brazes. Bubbles formed at the joint between the two water blocks indicating that the leak is a c seal problem. Pictures attached but also on docushare Collection-11285.

 Last night prior to this leak check the Heat Shield was pumped on and helium sprayed on the circuit. The pressure was 0.0 x 10^-4 Torr. The leak was traced to water block. response time was 2 seconds and went from 5.5 x 10^-8 to 1.6 x 10^-6 atm*cc/sec. There was also a response without spraying helium (drift from the nozzle). The results of this testing prompted the testing completed in Chads elog.

Bevan Moss wrote:

chad fisher wrote: The heat shield circuit was pressurized with air (15-20 psi) and snoop applied to the water block joint and brazes. Bubbles formed at the joint between the two water blocks indicating that the leak is a c seal problem. Pictures attached but also on docushare Collection-11285.  Last night prior to this leak check the Heat Shield was pumped on and helium sprayed on the circuit. The pressure was 0.0 x 10^-4 Torr. The leak was traced to water block. response time was 2 seconds and went from 5.5 x 10^-8 to 1.6 x 10^-6 atm*cc/sec. There was also a response without spraying helium (drift from the nozzle). The results of this testing prompted the testing completed in Chads elog.

 Please find attached some schematics which help illustrate the setup for this heat-shield circuit leak check.

The RGA showed no response to He-spray on the Service Cap. He stable at 3.5E-9 T partial pressure, water at 1.3E-6 T. IG1 at 9.9E-8 T

No leak detected on either He-detector (connected directly to Service Cap) or on RGA. See attached screen shots.

A vacuum increase (air only on RGA) was seen when de-pressurizing circuit I.

   I have fallen behind on the HV testing that has been completed on TM3. Data can be found on docushare in the TM3 Rev 3 folder files are too large to attach. From the last elog entry the following tests have been completed

July 8 2013 - Long HV conditioning 50kV achieved before sparking caused PS to trip. Was unable to recover to the same voltage

July 9 2013 - Attempted to repeat previous test lost PS at 45kV. Voltage continued to degrade during the day.

July 10 2013 - Max voltage achieve 42.5kV discussed with Friedhelm and decided to run the EINZEL lens at 50% of the BIAS in case this is the source of the sparking

July 10 2013 - Max voltage 40.5kV with EINZEL lens. Communicated with Friedhelm and Lia. It was decided 40kV was good enough. Started developing standard test (see below for testing procedure) for Module so a with and without source tray 

July 12 2013 - Only one spark on route to 40kV. PS tripped after ~10 minutes at 40kV. Near the end of the day there wasn't enough time to repeat test.

July 15 2013 - Test repeated, could not hold 40kV. 39kV held for 1 hour with EINZEL lens off. Sparking was making it difficult to keep on.

July 15 2013 - TM3 was electrically disconnected from the conditioning station. The station ran at 60kV for 1 hour with zero sparks.

July 16 2013 - Test repeated with goal of 39kV intense sparking after 20 minutes caused the PS to trip. Once again the EINZEL lens PS was tripping and eliminated from use to make the test easier. With the failure of this test once again Friedhelm was once again consulted. He advised to stop testing as it appears to be causing damage. There is concern that the module is degrading. Lia has stated this does not affect the source tray and that a source tray will be inserted into TM3 and she accepts responsibility if the module does not hold voltage. 

Standard testing procedure for the bias was as follows. Please note that the EINZEL lens was supposed to follow the BIAS steps at 50%. This procedure was approved by Friedhelm prior to operating. This test was never successfully completed and we will not be able to complete a "apples to apples" test once the source tray is installed.

> Step to 5000 kV If no sparking after 1 minute

> Step to 10000 kV If no sparking after 1 minute

> Step to 15000 kV If no sparking after 1 minute

> Step to 17500 kV If no sparking after 1 minute

> Step to 20000 kV If no sparking for at least 1 minute after 5 minutes

> Step to 22500 kV If no sparking for at least 1 minute after 5 minutes

> Step to 25000 kV If no sparking for at least 1 minute after 5 minutes

> Step to 27500 kV If no sparking for at least 1 minute after 5 minutes

> Step to 30000 kV If no sparking for at least 1 minute after 5 minutes

> Step to 31000 kV If no sparking for at least 1 minute after 5 minutes

> Step to 32000 kV If no sparking for at least 1 minute after 5 minutes

> Step to 33000 kV If no sparking for at least 1 minute after 5 minutes

> Step to 34000 kV If no sparking for at least 1 minute after 5 minutes

> Step to 35000 kV If no sparking for at least 2 minute after 10 minutes

> Step to 35500 kV If no sparking for at least 2 minute after 10 minutes

> Step to 36000 kV If no sparking for at least 2 minute after 10 minutes

> Step to 36500 kV If no sparking for at least 2 minute after 10 minutes

> Step to 37000 kV If no sparking for at least 2 minute after 10 minutes

> Step to 37500 kV If no sparking for at least 5 minute after 10 minutes

> Step to 38000 kV If no sparking for at least 5 minute after 10 minutes

> Step to 38500 kV If no sparking for at least 5 minute after 10 minutes

> Step to 39000 kV If no sparking for at least 5 minute after 10 minutes

> Step to 39500 kV If no sparking for at least 5 minute after 10 minutes

> Step to 40000 kV Maximum 3 sparks per hour maximum test time 3 hours.

 HV testing without the cover continued today. With the EINZEL lens at 30kV the target module was able to achieve 58.7kV. At this voltage any spark was reeking havoc on the electronics of the TCS. Vacuum gauges signals were occasionally lost, the thermocouple reading would occasionally be lost, turbo pump would turn off. All of these events caused the interlocks to trip resulting in the power supplies to be turned off. As a result I bypassed majority of the interlocks to prevent this from happening. Ultimately as spark took out the CANBUS controller first for the EINZEL lens and then for the BIAS. David Morris has been contacted to have them replaced. The damage of the CANBUS controller for these power supplies is becoming a common problem and should be investigated for if there is a better solution. During testing I experimented with raising the BIAS to near its limit followed by the EINZEL lens and vise versa. From this it was determined that the EINZEL must be raised to high voltage before the BIAS otherwise sparking occurs. Even a step from 0 to 500 volts on the ENIZEL lens with the BIAS at 55kV caused sparking. There are a few combinations of testing along this line I would like to continue with but initially my though is that the BIAS and ENIZEL do not have sufficient clearance for the BIAS to operate above 55kV. Attached is a screen shot of the strip tool and the data. I have not heard from David yet but I do not expect the TCS to be operational today. 

Feb. 16 2023: HV tests done on ITE station. Ramped up to 59kV but was not stable there, current draw was very unstable and was sparking every ~6mins. Ramped down to 58kV and it was stable there for 3 hours drawing 285uA.

Feb. 24 2023: HV tests done on ITW station. Ramped easily to 60kV with no sparking - suspicious. Has been stable at 60kV for 45mins with no sparks and current draw of 200uA. Cannot find any reason that things aren't connected properly...

TM2 is in the TCS without containment box for HV testing following the installation of the IGLIS wiring.

Not great results so far - sat at 42.5kV for nearly 2 hours, current around 200uA and occasional sparks. I did not have time to go higher, will do this tomorrow. The sparks could be conditioning but it looks a bit suspicious to me. We will see if the ramp up tomorrow is very easy and how high we can go. I have data from HV testing of TM2 in December for comparison.

The EZL was reacting to all sparks, so I went into the target hall to see if it was sparking on the module top, but there was no sparking there.

Possible mitigations:

1. Re-do the connections on top of the service cap to remove the extra length on the wires inside the service cap and inspect the routing carefully to make sure nothing is in the wron place.
2. Inspect the wiring in the source tray to see if there is evidence of sparking in a certain area.

Second round of testing Tuesday April 5 2022:

Much better results, seems most of the sparking was conditioning. Went right up to 42.5kV with no issues. Spent quite a while getting up to 50kV, and didn't leave it there for more than a couple mins. May be running into the limitations of the HV cage at this point. Bias current was much lower, something like 140uA at 45kV.

Third round of testing Wednesday April 6 2022:

Ramped easily back to 45kV, a little more sparking above that. Sat at 47kV for ~30mins with no sparks. Won't try to go higher in case of issues with the cage. Will try to condition up to 50kV in the station. Other than the possible low megger value between B and C, all looks good.

 High Voltage (HV) testing was completed on TM1 today. Vacuum was very good 1.9 x 10^-7 T in the service cap, 3.2 x 10^-7 in the containment box, and 2.0 x 10^-6 in the secondary. The voltage was successfully brought up to 27kV with a current draw of 0.12mA and o sparking. At the next step, 30 kV, the current draw was above 0.3mA and sparking was beyond 20 sparks per minute. The module should not be taken above 27kV. There is the possibility this voltage can be increased with conditioning but it is very unlikely. See attached for a graph of the testing. These results are comparable to the results without the source tray (see previous elog)

 This afternoon TM4 with the coil removed was tested with HV. The EINZEL LENS was first tested independently while the bias canbus was being repaired. The current on the EL looked stable at 25kV for 5 minutes. At 27.5kV the current becomes unstable and occasionally sparks. This voltage was held for 30 minutes but the current did not appear to be becoming more stable. Further extended testing would be required to determine if this can be conditioned out. At this point I would suggest the EL has a HV limit near 25kV.

The BIAS and EL were then brought up to 35kV and 17.5kV respectively. This voltage was held for 35 minutes with the BAIS only sparking twice. The module can most likely hold a higher voltage but for the next 2 runs does not require more than 35kV. Further testing was not completed due to time constraints. It is recommended during the shut down that TM4 is tested to its limits. The data from the testing has been attached.

BIAS only. Water lines looped on top. Containment box off.

Thursday, May 17, 2018, 11:20: Vacuum 7.2E-7 Torr

Thursday, May 17, 2018, 11:30: 10 kV

Thursday, May 17, 2018, 11:42: 20 kV

Thursday, May 17, 2018, 12:14: 25 kV

Thursday, May 17, 2018, 12:35: 30 kV

Thursday, May 17, 2018, 16:13: 35 kV

Thursday, May 17, 2018, 17:339: 37.5 kV

Thursday, May 17, 2018, 17:40: vacuum 6.8E-7 Torr

Thursday, May 17, 2018, 18:13: BIAS off.