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  Test-Stand, Page 40 of 53  Not logged in ELOG logo
Entry  Tuesday, March 26, 2019, 10:44, Aaron Schmidt, , , , , , , Problems/Solutions, EZL PS replaced. Test New_EZL_PS_testing_-_2019.docx

EZL checked. OK @ 5kV

BIAS PS issues.

2.3kV on screen. Read back on PS 3kV. Direct measurement reads 5.8 kV

Readback does not increase with the controls. Stops at 2.4kV & the current climbs very quickly.

Tuesday, March 26, 2019, 11:00: EZL PS routed to TS BIAS, but still controlled via EZL controls. EZL line grounded.

Brought up to 20kV, no sparks. 

New EZL PS confirmed ok. BIAS PS has issues.

Entry  Wednesday, March 27, 2019, 11:01, Aaron Schmidt, , , , , , , Problems/Solutions, BIAS PS replaced. Test NEW_BIAS_PS_testing_-_2019.docx

Wednesday, March 27, 2019, 10:25: BIAS @ 1 kV

952V - 548uA on controls readback - Scaling req'd

964V  direct from the PS - 25 uA

Wednesday, March 27, 2019, 10:28:

2.75 kV

2725V - 1515uA on controls readback

2696V  direct from the PS - 65.8 uA - Scaling req'd

Wednesday, March 27, 2019, 10:31:

5.5kV

5465V - 3022uA on controls readback

5.478kV  direct from the PS - 137.5uA - Scaling req'd

Wednesday, March 27, 2019, 11:00: PS runs ok. Longer connection cable req'd to link to TS source. Contact controls over scaling.

Wednesday, March 27, 2019, 14:25: Sources on. BIAS connected.

Wednesday, March 27, 2019, 14:34: BIAS / EZL @ 5.5 / 1 kV. No spark.

Wednesday, March 27, 2019, 14:51: BIAS / EZL @ 10 / 5 kV. No spark.

Wednesday, March 27, 2019, 14:57: BIAS / EZL @ 20 / 10 kV. No spark.


Scaling done IOC Restarted.

Thursday, April 04, 2019, 10:33: BIAS / EZL @ 20 / 10 kV. No spark.

Thursday, April 04, 2019, 10:35: BIAS / EZL / EE @ 30 / 13 / -1.5 kV. Anode at 200 V. No spark.

Thursday, April 04, 2019, 10:49: Sources brought to 0. No spark & scaling appears complete.

Entry  Friday, April 05, 2019, 07:02, Aaron Schmidt, , LP-FEBIAD, , , 395530-3, 42752-5, In progress, TS operation test - LP FEBIAD TS_-_New_BIAS__EZL_Testing_-_2019.docxTS-2019-04-05-07-00.rga

Due to previous issues, a full run / test should be performed on the ISAC Test Stand.

Friday, April 05, 2019, 07:00: RGA on.

Friday, April 05, 2019, 07:03: Begin opening / closing gas lines until they can be opened & stable.

Friday, April 05, 2019, 07:14: Gas lines open.

Friday, April 05, 2019, 07:16: Power / sources on. Vacuum down to 1.25e-06T

Friday, April 05, 2019, 07:18: Optics on & Set.

Friday, April 05, 2019, 07:19: IV4 Opened.

Friday, April 05, 2019, 07:21: Auto-ramping TGHT / TBHT to 300 / 200 A @ 2A per min

Friday, April 05, 2019, 07:28: BIAS / EZL / EE @ 30 / 13 / 1.5 kV. Anode @ 200 V.

Friday, April 05, 2019, 09:40: Auto-ramping TGHT / TBHT to 580 / 290 A @ 2A per min 

Friday, April 05, 2019, 14:01: Beam on FC0 & wire scans. Mass scan provides no reading. (Max current after CONST2 has changed). Inquire why.

No sparks have occurred on this run. Operationally, appears the PS switches were effective.

Friday, April 05, 2019, 14:05: Begin auto-cooling @ 2A per min.

Friday, April 05, 2019, 14:56 : BIAS / EZL / EE @ 0 kV. Anode @ 0 V.


Monday, April 08, 2019, 06:57: RGA off. Gas lines closed. IV4 Closed.

Monday, April 08, 2019, 07:01: Power / Sources off.

Monday, April 08, 2019, 07:01: IG1 off. Turbo pumps off.

Monday, April 08, 2019, 08:11: Venting.

Entry  Monday, April 15, 2019, 14:42, Aaron Schmidt, , LP-SIS, , , , 42972-1, Done, Conditioning UC#27 HS & test FS#3 UC#27_&_FS#3_check.docxTS-2019-04-16-08-20.rga

New coil lines installed for P2N testing later.

Monday, April 15, 2019, 14:15: Roughing.

Monday, April 15, 2019, 14:49: Turbo pumps on.


Tuesday, April 16, 2019, 08:20: RGA on.

Gradually open each line. Wait 5 minutes & monitor the response.

Tuesday, April 16, 2019, 08:30: Open Return & Supply main valves.

Tuesday, April 16, 2019, 08:32: Open FS#5. Vacuum @ 4.29e-06T. No response on RGA (water).

Tuesday, April 16, 2019, 08:37: Vacuum @ 4.37e-06T

Tuesday, April 16, 2019, 08:38: Open FS#4. Vacuum @ 4.37e-06T. No response on RGA (water).

Tuesday, April 16, 2019, 08:43 Vacuum @ 4.29e-06T

Tuesday, April 16, 2019, 08:44 Open FS#3. Vacuum @ 4.29e-06T. No response on RGA (water).

Tuesday, April 16, 2019, 08:49: Vacuum @ 4.26e-06T.

Tuesday, April 16, 2019, 08:50: Open FS#2. Vacuum @ 4.29e-06T. No response on RGA (water).

Tuesday, April 16, 2019, 08:57: Vacuum @ 4.29e-06T.


Wednesday, April 17, 2019, 08:30: Power/sources on. Vacuum @ 2.46e-06T.

Wednesday, April 17, 2019, 10:30: Auto-ramping TGHT  to 150 @ 2A per min. Vacuum limit increased to 3.000e-06T.

Wednesday, April 17, 2019, 11:53: Auto-ramping TGHT  to 300 @ 2A per min. Vacuum @ 2.50e-06T.

Wednesday, April 17, 2019, 13:10: Auto-ramping TGHT  to 350 @ 2A per min. Vacuum @ 2.95e-06T.


Thursday, April 18, 2019, 07:23: Auto-ramping TGHT  to 575 @ 2A per min. Vacuum @ 2.40e-06T.


Tuesday, April 23, 2019, 06:45: Auto-Cooling TGHT @ 2A per min. Vacuum @ 9.22e-07T. 

Tuesday, April 23, 2019, 08:29: RGA error. Shut off RGA.

Tuesday, April 23, 2019, 11:34: Power/sources off.

Tuesday, April 23, 2019, 11:37: IG1 off. Turbos off.

Tuesday, April 23, 2019, 12:53: Venting.

Entry  Tuesday, April 23, 2019, 14:39, Aaron Schmidt, , LP-SIS, , , , 42752-8, Done, Conditioning UC#28 HS  TS-2019-04-24-07-30.rgaUC#28_HS.docx

Tuesday, April 23, 2019, 14:39: Roughing.

Tuesday, April 23, 2019, 15:09: Turbo pumps started.

Tuesday, April 23, 2019, 15:18: Ion gauge on. 


Wednesday, April 24, 2019, 07:33: RGA on.

Wednesday, April 24, 2019, 07:37: Waterlines opened. Vacuum ok @ 7.99e-07T. No response on RGA

Wednesday, April 24, 2019, 07:41: Power / sources on.

Wednesday, April 24, 2019, 07:43: Auto-ramping TGHT  to 575 @ 2A per min. Vacuum limit remains at 3.000e-06T.


Thursday, April 25, 2019, 14:07: Auto-cooling @ 2 A per min.


Friday, April 26, 2019, 07:53: sources off.

Friday, April 26, 2019, 07:55: RGA off. Power off.

Friday, April 26, 2019, 07:57: Turbos off.

Friday, April 26, 2019, 08:00: HS waterlines purged.

Entry  Friday, May 03, 2019, 08:30, Anders Mjos, , , , , , , In progress, Training 

Training: Venting and pump down

Friday, May 03, 2019, 08:30: Turbo pumps stopped.

Entry  Wednesday, May 22, 2019, 13:47, Aaron Schmidt, , , , , , , , Calibrated Masscorr 

Wednesday, May 22, 2019, 13:44: Calibration Confirmed.

New Masscorr setup:

http://isacwserv.triumf.ca/onlylocal/isactdata/save_restore/masscorr/2019-05-22-13-42%20ZrC%238

Entry  Friday, June 07, 2019, 16:56, Carla Babcock, , , , , , , , TM4 source tray state 

TM4 source tray left in test stand over weekend, just the rouging pumps on. Ready to be removed Monday morning.


Monday, June 10, 2019, 06:35: Venting - Aaron S.

Entry  Monday, June 10, 2019, 14:34, Aaron Schmidt, , , , , , , Done, Removed TM4 Source Tray 

Monday, June 10, 2019, 09:30: TM4 Source Tray removed - To HC area.

Entry  Monday, June 10, 2019, 14:35, Aaron Schmidt, , , , , , , Done, Optics Tray / EZL inspection. 20190610_135100.jpg20190610_135926.jpg20190610_135045.jpg20190610_135517.jpg

Monday, June 10, 2019, 13:00: Optics Tray removed.

Megger'd @ 1000V on EZL and Collimator. Passed. Open it.

Monday, June 10, 2019, 14:34: 3 cracked insulators found. 1 quite broken on the threads (see attached pictures). Replaced insulators & re-assembled optics tray.

Megger'd @ 1000V on EZL and Collimator. Passed.


Thursday, June 13, 2019, 14:23: BIAS / EE / EZL @ 30 / -1.5 / 13 kV. EZL current @ 61 uA. EZL appears to be fixed. :)

Entry  Tuesday, June 11, 2019, 14:33, Aaron Schmidt, Test FEBIAD, LP-FEBIAD, , , 395530-3, 42752-5, In progress, ISAC Source tray re-installed w/ optics tray. 

Tuesday, June 11, 2019, 14:33: Roughing.


Wednesday, June 12, 2019, 08:18: Venting to install FEBIAD.

Wednesday, June 12, 2019, 09:13: LP-FEBIAD installed. Roughing.

Wednesday, June 12, 2019, 11:13: Turbo pumps on.

Wednesday, June 12, 2019, 11:21: Ion gauge on. 

Wednesday, June 12, 2019, 11:48: RGA re-connected & switched on.


Thursday, June 13, 2019, 10:27:

He Leak TEST:

Vacuum Group Leak detector LD#4.

Thursday, June 13, 2019, 10:28: Vacuum @ 1.60e-06T

LD Base line before opening valve to turbo pumps: 0.0e-09 atm-cc/sec

Thursday, June 13, 2019, 10:35: LD baseline after opening valve to turbo pumps: 1.2e-09 atm-cc/sec

Full open base:

Vacuum @ 1.60e-06T. RGA status:

Water: 2.20e-006

He: 4.55e-010

LD:  1.2e-09 atm-cc/sec

Thursday, June 13, 2019, 10:35:

Open line FS#2 . Pressurize to 30 PSI. Record after 5 minutes

Thursday, June 13, 2019, 10:40 Vacuum @ 1.54e-06T . RGA status:

Water: 2.20e-006

He: 4.20e-010

LD: 0.1e-09 atm-cc/sec. Purge and close FS#2.

Thursday, June 13, 2019, 10:45: Open line FS#3 . Pressurize to 30 PSI. Record after 5 minutes

Thursday, June 13, 2019, 10:50: Vacuum @ 1.52e-06T. RGA status:

Water: 2.18e-006

He: 3.68e-010

LD: 0.7e-09 atm-cc/sec. Purge and close FS#3.

Thursday, June 13, 2019, 10:50: Open line FS#4 . Pressurize to 30 PSI. Record after 5 minutes

Thursday, June 13, 2019, 10:55: Vacuum @ 1.54e-06T. RGA status:

Water: 2.16e-006

He: 9.24e-011

*LD: 3.7e-09 atm-cc/sec. Run for another 5 minutes.

Thursday, June 13, 2019, 11:00: Vacuum @ 1.52e-06T. RGA status:

Water: 2.15e-006

He: 2.06e-010

*LD: 0.7e-08 atm-cc/sec. Potential He escaping through o-rings*

Purge and close FS#4.

Thursday, June 13, 2019, 11:01: Open line FS#5 . Pressurize to 30 PSI. Record after 5 minutes

Thursday, June 13, 2019, 11:06: Vacuum @ 1.52e-06T. RGA status:

Water: 2.13e-006

He: 2.75e-010

LD: 1.7e-08 atm-cc/sec. Purge and close FS#5

Thursday, June 13, 2019, 11:07: Depressurize lines. Connect HPA & Purge all lines. 

Thursday, June 13, 2019, 11:12: Vacuum @ 1.54e-06T . RGA status:

Water: 2.12e-006

He: 6.21e-010

LD: 3.3e-08 atm-cc/sec

Close Valve & disconnect LD. HE LEAK TEST COMPLETE


Thursday, June 13, 2019, 11:20: Vacuum @1.52e-06T :Begin gradually opening the waterlines.

Thursday, June 13, 2019, 11:22: Open FS#2. Vacuum @ 1.52e-06T. No Response on RGA.

Thursday, June 13, 2019, 11:23: Open FS#3. Vacuum @ 1.52e-06T. No Response on RGA.

Thursday, June 13, 2019, 11:23: Open FS#4. Vacuum @ 1.52e-06T. No Response on RGA.

Thursday, June 13, 2019, 11:24: Open FS#5. Vacuum @ 1.52e-06T. No Response on RGA.

Thursday, June 13, 2019, 11:28: Power sources: Tested. TGHT PS is still a no go. Power switched off, lock out.

Thursday, June 13, 2019, 14:03: New TGHT PS installed.

Thursday, June 13, 2019, 14:06: Power / sources on.

Thursday, June 13, 2019, 14:20: BIAS / EE / EZL @ 30 / -1.5 / 13 kV. EZL current @ 61 uA. EZL appears to be fixed. :)

Thursday, June 13, 2019, 14:21: Spark*

Thursday, June 13, 2019, 14:29: Sources to 0 kV. FS#8 needs re-connection.

Thursday, June 13, 2019, 14:43: FS#8 connected. Vacuum ok @ 1.52e-06T. No response on RGA.

Thursday, June 13, 2019, 14:45: Auto-ramping TGHT / TBHT to 300 / 150 A @ 2 A per min.


Friday, June 14, 2019, 06:52: Restart RGA.

Friday, June 14, 2019, 08:37: Run mini pump to prep gas-lines.

Friday, June 14, 2019, 08:44: Close SV1, manual valve & turn off mini pump. Gradually open gas lines.

Friday, June 14, 2019, 08:48: Gas lines fully opened.

Friday, June 14, 2019, 08:49: Auto-ramping TGHT / TBHT to 570 / 270 A @ 2 A per min.

Friday, June 14, 2019, 08:52: HV sources ready.

FM

Friday, June 14, 2019, 11:11: Anode current @ 0V 7.326mA. Setting Anode to 150 V.

AS

Friday, June 14, 2019, 11:16: Auto-ramping TGHT / TBHT to 580 / 290 A @ 2 A per min.

Friday, June 14, 2019, 11:18: Optics set.

Friday, June 14, 2019, 11:29: BIAS / EE / EZL @ 30 / -1.5 / 13 kV. One spark while bring the BIAS to 30 kv around 27.5 kV. IV4 opened.

Friday, June 14, 2019, 14:39: Multiple wire scans attempted since 1pm. Controls & Diagnostics contacted. Ongoing troubleshooting.


Monday, June 17, 2019, 08:34: TMS:MB1 - Reset. 

Monday, June 17, 2019, 09:18: Auto-ramping TBHT to 310 A @ 2 A per min.

FM

Monday, June 17, 2019, 10:30: TBHT manually tapped to 320 A  ~2A/min


Tuesday, June 18, 2019, 18:42 : BIAS / EZL / EE @ 0 kV. Anode @ 0 V.

Tuesday, June 18, 2019, 18:43: Begin auto-cooling @ 2A per min.


AS

Wednesday, June 19, 2019, 07:10: IV4 Closed.

Wednesday, June 19, 2019, 07:12: Gas lines & Sources / power off.

Wednesday, June 19, 2019, 07:15: RGA off.

Wednesday, June 19, 2019, 07:16: IG1 & Turbo pumps off.

Wednesday, June 19, 2019, 08:35: Purging / venting.

Entry  Thursday, June 13, 2019, 14:05, Aaron Schmidt, , , , , , , Done, Spare TGHT PS installed. 

Thursday, June 13, 2019, 14:04: Spare TGHT PS installed /  tested. The old one is to be sent out for repair.

 

Entry  Wednesday, June 19, 2019, 17:25, Fernando Maldonado, , , , , , , Done, Thermocouple connection 

Wednesday, June 19, 2019, 17:13  Ferran and Fernando tested the 9-pin connector to have a reading on a thermocouple following the connections used by Aurelia (see elog 721).

Wednesday, June 19, 2019, 17:24: Test succesful!

 

 

Entry  Friday, June 21, 2019, 15:12, Aaron Schmidt, P2N - 1, , , , , , , P2N - 1 - 2019 

Friday, June 21, 2019, 14:48: Roughing.

Friday, June 21, 2019, 15:18: Turbo pumps on.

Friday, June 21, 2019, 15:31: IG1 on.

Friday, June 21, 2019, 15:42: Vacuum@9.31e-5 T

Friday, June 21, 2019, 15:51: RGA switched on.

Friday, June 21, 2019, 16:30: Luca wants to put heat shields on his target. Aborting pumping. 

Friday, June 21, 2019, 16:57: IG1 off 

Friday, June 21, 2019, 16:57:  Turbo pumps off.

 Friday, June 21, 2019, 16:57: RGA switched off


AS

Monday, June 24, 2019, 07:18: Restart TP1A (Timeout) Global Reset. Restart again.

Monday, June 24, 2019, 07:29: TP1A to speed. Monitor. Vacuum @ 4.31e-06T

Monday, June 24, 2019, 07:31: Restart RGA.

Monday, June 24, 2019, 08:57: Waterlines opened. No response on RGA. Vacuum @ 3.23e-06T.

Monday, June 24, 2019, 09:03: Power / sources on. (No HV)

Monday, June 24, 2019, 09:04: TGHT / TBHT / Coil PS ready.  Vacuum @ 3.23e-06T.

Monday, June 24, 2019, 10:09: Auto-ramping TGHT / TBHT to 150 / 75 A @ 2 A per min. 

Monday, June 24, 2019, 10:57: Auto-ramping was halted @ 35 A. Coil increased. TGHT, TBHT, Coil brought back to 0 A

Monday, June 24, 2019, 10:58:

 Device Temp
[C]
 Flow
[lpm]
 HS + MSP 26.27 5.47
 TBHT 26.11

8.20

 COIL + EE 26.03 2.36
 TGHT  26.12 6.33

 Monday, June 24, 2019, 11:01: Auto-ramping TGHT / TBHT to 150 / 75 A @ 2 A per min. Manually ramp coil to 150 A @ approx the same rate.

Monday, June 24, 2019, 12:20: Halt at 140A TGHT / Coil. Vacuum limit?

Monday, June 24, 2019, 13:23: Increasing good vac limit. From 3e-6 to 4.5e-6 T

Monday, June 24, 2019, 13:29: Auto-ramping TGHT / TBHT to 300 / 120 A @ 2 A per min. Manually ramp coil from 140 to 150 A @ approx the same rate.

Monday, June 24, 2019, 13:37

 Device Temp
[C]
 Flow
[lpm]
 HS + MSP 26.97 5.95
 TBHT 26.82

8.62

 COIL + EE 26.70 2.60
 TGHT 26.80 6.54

 Monday, June 24, 2019, 14:4: TGHT @ 270 A. Vacuum limits reached 3.05e-06T. Gradual out-gassing w/ cont'd auto ramp.


Tuesday, June 25, 2019, 07:53: Auto-ramping TGHT / TBHT to 550 / 120 A @ 2 A per min.

Tuesday, June 25, 2019, 08:34:

 Device Temp
[C]
 Flow
[lpm]
 HS + MSP 25.30 5.75
 TBHT 25.08

8.40

 COIL + EE 24.96 2.47
 TGHT 25.08 6.55

Tuesday, June 25, 2019, 10:09: At approx 9:45am a vacuum spike tripped the test stand. All heaters at 0 A. Power supplies checked.

Tuesday, June 25, 2019, 10:11: TGHT / TBHT / Coil @ 6 A. Bumped up manually.

Tuesday, June 25, 2019, 10:12: Auto-ramping TGHT / TBHT to 300 / 100 A @ 2 A per min. Manually ramp coil to 150 A.

Tuesday, June 25, 2019, 11:01: One sheet on the target leg is shining red.

Tuesday, June 25, 2019, 11:01: Aborting the ramping.

Tuesday, June 25, 2019, 11:08 :

 Device Temp
[C]
 Flow
[lpm]
 HS + MSP 27.50 6.29
 TBHT 27.28

8.88

 COIL + EE 27.20 2.74
 TGHT 27.30 6.73

Tuesday, June 25, 2019, 11:18: Continue auto ramping

Tuesday, June 25, 2019, 11:37: Auto-cooling @ 12 A per min. Coil tapped down manually.

Tuesday, June 25, 2019, 11:58: Sources off. RGA off. Power off.

Tuesday, June 25, 2019, 11:59: IG1 off. Turbos off.

Entry  Saturday, June 22, 2019, 17:05, Luca Egoriti, p2n, , , , , , Done, Test stand installation 

I opened the test stand because I forgot to install tantalum heat shields around the target. Everything was reinstalled as before (with heat shields). I could turn on the TSGTP1B but TSGTP1A does not turn on for some reason. I tried multiple times opening/closing its valve (BV1A) but the pump never starts.

Will keep pumping over the weekend with TP1B only.

Entry  Monday, June 24, 2019, 15:41, Fernando Maldonado, , , , , , , Problems/Solutions, TMS:Q3 polarity 

Monday, June 24, 2019, 15:25: Current quadrupole polarities:

  Top/Bottom North/South
TSP Q1 Positive Negative
TSP Q2 Negative Positive
TSP Q3 Positive Negative
TSP Q4 Negative Positive
TMS Q1 Positive Negative
TMS Q2 Negative Positive
TMS Q3 Negative Positive
TMS Q4 Positive Negative
TMS Q5 Negative Positive
TMS Q6

Positive

Negative

 

Monday, June 24, 2019, 15:35 : The polarity on TMS:Q3 is reversed. The top and bottom poles should be at a positive voltage similar to TMS:Q4, however a negative tagged cable is connected to it.

Monday, June 24, 2019, 15:39 : Swapping the cables on TMS:Q3.

 

  Top/Bottom North/South
TSP Q1 Positive Negative
TSP Q2 Negative Positive
TSP Q3 Positive Negative
TSP Q4 Negative Positive
TMS Q1 Positive Negative
TMS Q2 Negative Positive
TMS Q3 Positive Negative
TMS Q4 Positive Negative
TMS Q5 Negative Positive
TMS Q6

Positive

Negative

 

Entry  Tuesday, June 25, 2019, 17:19, Fernando Maldonado, , , , , , , Problems/Solutions, Burnt cables on top of the test stand 20190625_154015.jpg20190625_153834.jpg20190625_165001.jpg

Tuesday, June 25, 2019, 16:15: While inspecting the 9-pin connection with Ferran, it was noticed how two braided cables were burnt out pretty bad to the point they were separated in half (see attached pictures).  Additionally the plastic insulator for the anode wire was melted.

Tuesday, June 25, 2019, 16:30: Braided cables need to be changed and anode wire redone. 

Tuesday, June 25, 2019, 17:16: Wondering if this happened during TM4 source tray conditioning given the following entries in the elog (entry 725):

Monday, June 03, 2019, 09:51: BIAS down to 50 kV. Burnt plastic smell lingering. Wait* 

Tuesday, June 04, 2019, 10:29: Note* Minute fluctuations of Anode current have ended after the spark. Also slight 'Burnt' smell noticed around the test stand area.

 

Entry  Wednesday, June 26, 2019, 14:41, Carla Babcock, none, , , , , , Problems/Solutions, Issues with test stand wiring in service cap area isk4523d_ITSrewiring_June2019.png

The wiring on the top of the test stand was burned, see entry 737.

Probable cause of this is as follows:

Coil lines are connected by a wire to HV common, the 9-pin feedthrough etc to maintain same voltage on all the insulator tops. This is also directly connected to the extraction electrode spark gap. When this sparks, it momentarily changes the potential in that line (normally HV common) which then can make this path the best route for current from the coil to return to ground.

See attached diagram.

 

Best solution to this problem is to disconnect the high current section from the low current section, and attach each separately to HV common.

Other possible improvements to wiring:

1. Remove jumpers between positive coil lines (and neg. coil lines) since these feethroughs are physically connected by the copper pipe.

2. Add a resistor to the jumper between coil - and TBHT - since this will eliminate all possibility of current flowing between the two.

3. Add a resistor in line where the high current section is connected to HV common to avoid possibility of current going through jumpers.

Entry  Thursday, June 27, 2019, 09:51, Fernando Maldonado, , , , , , , Problems/Solutions, Melted cables changed 

See elog 737 

Fernando Maldonado wrote:

Tuesday, June 25, 2019, 16:15: While inspecting the 9-pin connection with Ferran, it was noticed how two braided cables were burnt out pretty bad to the point they were separated in half (see attached pictures).  Additionally the plastic insulator for the anode wire was melted.

Tuesday, June 25, 2019, 16:30: Braided cables need to be changed and anode wire redone. 

Tuesday, June 25, 2019, 17:16: Wondering if this happened during TM4 source tray conditioning given the following entries in the elog (entry 725):

Monday, June 03, 2019, 09:51: BIAS down to 50 kV. Burnt plastic smell lingering. Wait* 

Tuesday, June 04, 2019, 10:29: Note* Minute fluctuations of Anode current have ended after the spark. Also slight 'Burnt' smell noticed around the test stand area.

 

 

Thursday, June 27, 2019, 09:45: The cables showing burnt marks were changed with new ones on Wednesday 26th. The grounding cables were insulated with yellow heatshrink. The anode wire connection was redone.

Entry  Tuesday, July 02, 2019, 18:25, Fernando Maldonado, , , , , , , Done, Blank on FEBIAD gas line installed 20190702_182254.jpg

 Tuesday, July 02, 2019, 18:24: A blind is installed  on the FEBIAD gas line (see attached picture)  to rule out the possibility of  gases entering the TIS.

ELOG V2.9.2-2455