TM3 with target UCx#44 was disconnected in ITE. 

TM3 UCx#44 after operation electrical check at SHC . see attachment.

Carla: Looks like the short on the cathode observed while trying to operate the FEBIAD in cathode-bias mode is still there. Will do investigations in the hot cell during disassembly.

Tm3 has been moved form ITE to SHC. the move is smooth.

A new gas system for FEBIAD operation was installed in ITE to enable us to use a calibrated leak which is attached to the target heat shield. This will allow us to control the quantity and purity of the gas going into the system, and to switch quickly between gasese and pressures.

The schematic of the system is attached. The use of the ballast container is likely not needed - it was originally included in case we want to run the system at pressures greater than 1 ATM. The roughing pump inlet limit is 1ATM, so it was envisaged to used the ballast container to reduce the pressure to that level or below before opening the system to the pump. But since it has been difficult to commission the system over 1ATM and this opens the door to several concerns about gas leakage, it was deemed better to keep operation below 1 ATM. This tank will likely be removed.

The storage tank was implemented because we are not sure if irradiated gases will be pulled out of the target lines when we pump on them, and so this was devised as a way to test that. The alternative is to have the exhaust of this pump go directly into nuclear ventilation by way of a plastic tube leaving the faraday cage, however this solution is also quite some work to implement. So the consensus was to start with the storage tank and sample it several times to understand what sorts of radioactivity we are dealing with, then make a decision about future operations.

This system has been tested offline using the development target UCx#44 and appears to work well. Unfortunately there were no protons available for this beam time so the gas sampling part of the system was not tested.

The operation of the rest of the system worked reasonably well. Beam disappeared when pumping out the lines and reappeared when re-opening the gas bottle. It seems that the storage container can be used to pump out the lines about 7 times before it gets up to around atmosphere, as was estimated based on volume. The pump can get the lines down to about 250mTorr as read by the pressure gauge DG2 on the module top, given about 30mins of pumping.

We did have some issue with the gauges, HV sparks destroyed both controllers and so we were unable to monitor pressures as we would have liked. It is possible one gauge itself is broken as well, to be investigated.

It may be that the gas leak we used was too small, but the idea of changing the pressure on the module by changing the needle valve didn't seem to work. This is not sure since we didn't have a reading on the pressure, but watching the ion beam as you turn the gas back on seemed quite binary. You would see no change until you had the needle valve fully open. This may be different with a larger leak, since this leak required about 1ATM in the lines to see anything. It is still not clear why this behaviour was different than the tests at the test stand, in which 0.5ATM of upstream pressure produced about 2nA of beam.

This system is considered a prototype and is not turned over to ops for operation. Further commissioning is required.

Tm3 electrical check without target is done. Everything is good including 2 x 5 pin connectors( all OL at 250 V to 60 KV and each other)  see attachment.

TM3 has been moved  from SHC to TCS.The move is smooth.

Tm3 electrical check with SiC#46 target  and HS line helium spray check at SHC. were done. everything is good. see attachment.

TM3 and UCx#44 ran in ITE but issues with the cyclotron prevented proton beam delivery. Nonetheless, the target was heated and provided stable beam to TITAN as well as for tuning and some tests.

Results of inspection of TM3 module after run:

The module looked pretty good. There were no marks on the polished surface of the containment box, next to the water blocks, that were visible. But we didn't remove the box, only looked with the camera and it was visible by turning the module. So some things may have been hidden. There were some black marks on the door, near the bolts that hold in the handle (see attachment). This seems a very unlikely spot for sparking as the fields should be considerably lower than at the target handles, lower down. Maybe the spots are from oil left on the door that had a chemical reaction? There is one very faint matching spot on the top of the copper trident connector, but it doesn't look much like a spark mark. The other two marks have no corresponding mark on the source tray. There were no marks on the ground electrode, or anywhere else on the source tray. There was a scuff on one of the trapezoidal insulators, but it could have happened during installation.

Results of inspection of the target after run:

The FEBIAD target developed the same cathode short we have seen on almost every FEBIAD we run online - a high resistance short from cathode to HVC that prevents voltage on the cathode. This time the short remained after cooling the target, and David measured 208kOhms with the ohmmeter on the module top (11kOhms with the megger). We used a multimeter in the hot cell to test after the target had been dismounted and we found no short. So it must be related to either the position of the target (upright vs face down) or time (a conductive trace on an insulator oxidizes and becomes non-conductive again) or some pressure/shaking during the de-installation.

There weren't many marks on the target - a faint mark near where the faint mark on the copper trident was observed, some marks on the EE which had no counterparts on the ground electrode. See pictures.

Tm3 has been moved from TCS to ITE. the move is smooth.

Tm3 has been moved from TCS to ITE. the move is smooth.

 TM3 with new target SiC#46 was connected in ITE.

Initial Summary:

TM3 sparking behaviour in ITE has been very disruptive both with and without protons. Protons are at 60uA, target heater at 540A. Max voltage achieved so far is 51kV, limited by time and a current limit on the BIAS supply.

The ITE:EL trips off every couple of minutes. Just needs to be restarted. Mike investigated and found that the trip is happening inside the power supply, then a moment later the canbus is defining the supply off when it cant get it to respond. Trip frequency decreased over time but still disruptive.

All the waterflow signals, including ones controlled in the cyclotron system, were tripping off regularly. These have all been forced, then we implemented a 5s delay in the ISAC waterflow interlocks. This seems to have solved the issue.

The ITE:BIAS supply has also been limited at 500uA instead of 5mA. Probably something hardcoded into the canbus - this was fixed by Keiko and the hardcode limit was set to 20%(?) of 5mA.

TM3 has been very sparky, even at low voltages. I can't understand why. A new ground path would be explicable but the excessive sparking is difficult to understand.

Possible avenues:

1. make sure the module outer surface is connected through a copper sheet to the sheet on the wall.
2. check that special ground still grounds all the gnd power supplies in the electrical room - this I checked but some of the grounds are connected through wires instead of sheets, this can be improved.
3. try running the module with only HV hooked up and nothing else.
4. try running TM3 in ITW.
5. Search work permits and shutdown jobs for any changes made to the system that could affect this.
6. hope there is a software solution for the EL problem, or start moving towards PLC control - no software solution because the canbus card is only reacting to the power supply refusing to turn on, so it seems the issue originates in the PSU. Moving to PLC is possible but may not help and increases the risk of frying the PLC module.
7. Add a spark gap or limiting resistor to the EL somewhere. Resistor only helpful if the EL itself is sparking. Difficult to find a spot for the spark gap.
8. Get a bipolar supply that can sink the current of a spark and replace the EL supply. - Tomislav doesn't seem to think this is viable.
9. Add protection on the controls cables.

Spark recording:

60uA/50kV/540A July 3 02:30 - 05:30 : average of 50 sparks per hour. data file https://isacwserv.triumf.ca/onlylocal/isacdata/ITE_TM3_SiC46_HVConditioning_2_20240704

60uA/32kV/540A July 3 19:15 - July 3 21:45 : average of 8.4 sparks per hour. data file https://isacwserv.triumf.ca/onlylocal/isacdata/ITE_TM3_SiC46_HPSIS_HVConditioning_20240704

50uA/42.8kV/540A July 4 8pm - July 5 2pm : average of 20 sparks per hour, or if you cut out the last two hour that were very sparky, 14 sparks per hour. data file http://isacwserv.triumf.ca/onlylocal/isacdata/TM3commissioning_July4_52024.dat

50uA/42.8kV/540A July 8 00:00 - July 8 18:00 : average of 3.4 sparks per hour. data file http://isacwserv.triumf.ca/onlylocal/isacdata/TM3commissioning_July82024.dat

50uA/42.8kV/540A July 10 10am - 3pm : 3.6 sparks per hour

50uA/53kV/540A July 17 5am - 10am : 4 sparks per hour

45uA/53kV/540A July 20 8pm - July 21 6:30am : 24 sparks in 11 hrs, avg 2.2 sparks per hour.

EL trip recording (first 2 entries from the archiver, verify with ops elog):

50uA.42.8kV/540A July 4 23:00 - July 5 16:00 : 9 trips, average 0.5 trips per hour

50uA/42.8kV/540A July 6 12:00 - July 7 03:00 : 6 trips with 2.5hrs off, average 0.5 trips per hour

50uA/42.8kV/540A July 7 05:00 - July 8 18:00 : no trips in past 30hrs. Last trip July 7 at 3am.

50uA/42.8kV/540A July 10 3pm - still no EL trips

50uA/53kV/540A July 16 8pm - July 17 10am : 3 trips in 6 hrs. Note cable in EL circuit got burned so EL is running at only ~4kV

45uA/53kV/540A July 17 3pm - July 18 9:30am : 7 trips in 18hrs

45uA/53kV/540A July20 14:00 - July 21 6:30 : 5 trips in ~17hrs

2024-11-15 EDIT, Alexander Shkuratoff:

I was not involved in this run, but I have gone through all the Elogs for TM3 up to this point and summarized all the data dumps at the bottom, so I may as well do it here.

	ITE_TM3_SiC46_HPSIS_HVConditioning_20240704	2024-07-04 01:42	4.8M
	ITE_TM3_SiC46_HVConditioning_Vac_20240704	2024-07-04 01:59	5.3M
	ITE_TM3_SiC46_HVConditioning_2_20240704	2024-07-04 05:31	1.1M
	TM3commissioning_July32024.dat	2024-07-04 17:04	11M
	TM3commissioning_July4_52024.dat	2024-07-05 14:18	12M
	TM3commissioning_July82024.dat	2024-07-08 18:03	13M

 Additionally, there is no Elog entry for August 18, 2024 for which TM3 commissioning continued in ITW, but I have found the following StripTool data:

	TM3commissioning_Aug182024.dat	2024-08-18 05:37	14M
	TM3commissioning_Aug182024_2.dat	2024-08-19 06:16	14M

 TM3 with spent target SiC#46 was disconnected in ITE and ready to move to TCS soon.

Tm3 was moved from ITE to TCS this Tuesday, then to SHC  this morning. Both moves are successful.

ABCD is short to 60KV bias. Othjer are ok.  see attachment.

Found afterwards that this short was due to sparking through the multipin wire insulation where the wires pass behind the TBHT block "C". See fault 17265.

 TM3 with replaced target TiC#8 has been checked on SHC before moving to ITW. Pls see attachment

With TiC # 8 installed, TM3 has been moved from SHc to ITW. The move is smooth.

TM3 has been connected in ITW. See attachment for checklist.

With the new TiC#8 target installed on TM3, there was a ~7kOhm connection between TGHT/TBHT (A/B/C/D) and HV common. The standard electrical check on the module showed standard values, so it was assumed the problem was inside the target.

Started removing bolts/water connections one by one to see if any of them had an effect on the measurement. Found that disconnecting the multipin on the target from the mating connector on the source tray resolved the issue. Determined that the only way this could happen is if a spark cut through the insulation covering the multipin wires. Because of the way they are routed, they can touch the water lines and they are definitely touching waterline C, TBHT-. We do not typically check continuity of multipins to all water lines, just to HVC, so did not see this in the standard electrical check. Measurements verified that pin 2-4 was touching water line C, creating a short from TGHT/TBHT to HV common when the multipin connector is attached, since the pins are shorted to HVC inside the connector when they are not used.

Issue was solved by removing the target into the ante room, removing connector 1 all together since it was not used, and removing the grounding on the other pins, leaving only pin 2-2 connected for the anode.

In future we will change the IGLIS wiring so pin 2-4 is not used, and redesign the cable routing so it cannot touch the blocks. For the immediate term, we will add to the electrical check a check of each pin to TBHT/TGHT/COIL.

TM2 with Ta#target has been moved from SHC to ITE. the move is smooth.