TM4 has been moved from SHC to TCS. the move is smooth.

electrical check and leak check were done on TM4 UCx#45 target at SHC.  everything is ok. See attachment

helium pressure test on TM4 HS line at TCS is done.   No leak.

On Wednesday, May 22, 2024 UCx#45 was installed on TM4 in the SHC. Installation was normal other then minor issue with the multipin connector drive screw not engaging and/or driving properly. This was remedied by loosening the left guide bolt slightly (1/2 turn). After loosening the multipin drove in and seated correctly (verified by camera). High current fasteners torqued to 130 in lbs.

TCS was argon vented this morning between 6:00 and 7:30am for TM4 moving to ITW.

Tm4 has been moved from TCS to ITW.  the move is smooth.

 TM4 with new target UCx#45 was connected in ITW this morning. pls see attachment uploaded with.

 5 shielding blocks have been transferred from ITE to ITW. 

Doc # 181007

ITW has been behaving badly at higher voltages recently, even without protons on. I conditioned it up to 50kV with heaters off in the TCS and it was fine. But when I tried to do the same with heaters on in the station, it was quite sparky and it kept tripping the TGHT/TBHT. I went to 49kV where it was unstable, then lowered to 48kV where it looked fine for 30mins. But even operating at 40kV, it tripped the heaters several times. The TBHT voltage came back lower than before on the last trip, so I am getting worried about it.

I decided to make sure all the electronic spark protection was ok in the faraday cage. There is a resistor/gmov combination across the terminals of each TGHT/TBHT in which Tomislav replaced the gmovs for me because his tester did not work at those low voltages, so we couldnt see if they were broken. The electronics diagram called for 18V gmovs, the replacements are 22V because that's all we have.

We also tested and re-installed the capacitor-gdt-resistor combinations that John installed last year from TGHT/TBHT bubars to HV common. I originally removed them because we couldn't bias a FEBIAD with them on - this still has to be investigated. The measured values are 0.148uF, 90kOhms and a breakdown voltage on the gdt of 410-450V.

Hopefully this prevents sparking the power supplies off.

Sunday, June 16, 2024, 07:03 : power supplies have not tripped off since electronics repair. See data/TM4sparkingbehaviour_June152024.dat for sparking frequency over ~10hrs of protons (5-14uA). >14 sparks during this time (14 captured by PLC when voltage dropped, many more current peaks).

TM4 with spent target UCx#45 was disconnected in ITW and moved to SHC.

 TM4 move from ITW to SHC is smooth.

electrical check  on TM4 UCx#45 target at SHC after operation is done.   see attachment.

TM4 and TiC#7 target electrical check and HS leak check at SHC after target installation have been done.  all results are good. I will attach the checklist when printer is back to work.

TM4 HS line was helium pressure tested at TCS this morning. No leak. Also i leak checked TM4 top all air to  vacuum seals at TCS. Everything is good.

TiC #7 is a febiad target.TM4 top has been configured for febiad target. checked pin 2-2 to bias, target ,and chassis at 250V. they are all OL.  

TM4 has been moved from SHC to TCS. The move is successfully.

TM4 has been moved from TCS to ITW.  the move is smooth.

TM4 has been moved from TCS to ITW.  the move is smooth.

 TM4 with TiC#7 was connected in ITW, all TPs are running at full speed.

 TM4 with spent target TiC#7 (dead) was disconnected in ITW and ready to move to TCS.

Tm4 has been moved from ITW to SMP. the move is successful.

TM4 has been moved from  SMP to SHC. The move is smooth.

 New target Ta#68 is installed on TM4 and be leak/electric checked. Pls see attachment.

 TiC#7 Target Removed from TM4. - Photos attached 

TiC#7 Currently sitting in SHC waiting for disposal