electrical checked in ITW

Frank and I finished ITW and TM2 leak check. TM2 internal water-cooling lines are leak free. They passed 70 psi helium pressure test. We found some small leaks on ITW primary and secondary vacuum vessel. I list them here:

1. Exit module 2 service cap top plate to cap body O-ring at SW corner. Leak rate 2XE-8 atm.cc/sec. It is an old leak we found before. Solution: I sprayed high vacuum resin to leak area. It is improved to 3Xe-9atm/sec now. We can leave it there.

2. Exit module 1 module to tank flange o-ring at target module side and north side. Leak rate 3XE-8atm.cc/sec. Solution: replace the o-ring. It involves in disconnect exit module 1 and remove it out. We may or may not change it. Let's check the schedule and discuss it later. We need Travis help on module moving out.
   
3. Exit module 1 north side sqaure service panel o-ring. Leak rate 2XE-7 atm.cc/sec.  Solution: replace the o-ring. It is a straight forward job.  It will be done this shut down.
   
4. Exit module 1 north side round roughing valve panel o-ring. Leak rate 8XE-9 atm.cc/sec. Solution: Replace the o-ring. It involves in disconnecting and removing ITW RV4.  It could be done this shut down.
   
5. Big T tank o-ring seal underneath the flange at exit 1 module north side . Leak rate 3XE-8 atm.cc/sec. Solution: None. All modules and module base flange have to been moved out to replace this big o-ring.  It is a huge project to change this o-ring .  I checked this big o-ring seal every year. It is first time a small leak is found.  Maybe, we could try high vacuum resin spray first.
6. Dump module flange o-ring at the side by Target module. Leak rate 8XE-9 atm.cc/sec. It cannot be confirmed since the TM o-ring is just beside it. Mostly, the leak is on dump module side. We changed TM flange o-ring every year. But we never changed dump module flange o-ring in history. Many copper cooling lines above the dump module has to be removed to remove the dump module out. I do not think we have time to do it this year. Also,  the leak rate is pretty small. Maybe, we can schedule it next year.

  Most these small leaks are close to turbopumps. This could be the reason the ITW vacuum on gauges are still pretty good.

Travis and Nadia moved TM2 from ITW to NHC this morning. The move is smooth and successful.

TM2( no target ) has been moved  from NHC to SMP.  The moving is smooth and successful.

 An electric check was done right after module moving from SMP to SHC. 

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.

Chad changed the EZL cable and plugs on TM2. New cable runs along the cable trays.

 A Test Febiad Target was installed and checked at SHC. 

 TM2 was connected in ITW with a Febiad Test Target. 

Annual ITW water signal interlocks check was done with TM2 in ITW.   Water signal interlocks on all water circuits related to TM and 2A beam lines in ITW work fine. 

 TM2 with a test target was disconnected in ITW.

 An electrical check was done at SHC for TM2 with FEBIAD SiC #42 Target. 

 TM2 with Febiad target SiC#42 was connected in ITW.

On June 2 2022, while attempting to install target SiC#42 a gasket fell off the water line. I attempted to remove the target to have the gasket reattached, however the multi pin connector guide pin was loose and was preventing the target from being removed. During the attempt to remove the target it was noticed that an electrical cable in the back of the module had become loose and was dangling. The target was then secured to the module, and then the module was moved to the SHC to complete the job/repairs.

June 3 2022, containment box was removed, Einzle Lens cable reattached and tested, and the multi pin guide pin was retightened.

On June 6 2022, the containment box was damaged while lifting the containment box back onto the module.

The left rear corner of the box caught on the module and the corner weld snapped and folded the corner down about 90 degrees.

With help from Chad, we were able to restraighten the corner with a C-clamp, enabling the box to be reattached to the module.

However the 2 bolts that were on the corner that attach to the module were not able to be aligned and were not used.

The target was reattached to the module, and to save time was brought directly to ITW, skipping the conditioning station. 

 An electrical check was done at NHC, see attachment pls.

 TM2 with new target SiC#43 was electrical checked at SHC. please see attachment.

 While removing the SiC#42 it became apparent that the multipin guide pin had become loose again and was not allowing the target to dismount from the module.

The multipin shoulder bolts were removed and then the multipin was able to be pried off.

However the NHC manipulator were not able to reach the guide pin to remove it, which would be required before the SiC#43 could be installed.

The target module was then moved to the SHC where the guide pin could be removed and the installation of SiC#43 took place, along with the transfer of the parasitic attachment onto the SiC#43.

This problem seems to suggest that the multipin could use some redesign to ensure smoother target exchanges.

 TM2 with Febiad Target SiC #43 was connected in ITW. NOTE: the number of TARGET in attached picture should be #43. 

Monday morning June 20th: TM2 with SiC # 42 was moved from ITW to NHC.

Monday afternoon: TM2 with no target was moved from NHC to SHC due to 10 pin connector guide pin loose issue. The guide pin has to be moved out in SHC due to NHC manipulator configuration limit .

Monday afternoon: TM2 with SiC # 43 was moved from SHC  to ITW.

all module moves are smooth.

 the module was disconnected in pit and moved to NHC.