Tests on coil, temperature and the use of silver bolts.
(3) Vented silver bolts on the TBHT and (2) Full silver bolts on the coil
Wednesday, March 21, 2018, 14:10: Roughing.
Wednesday, March 21, 2018, 14:30: Turbo pumps on.
Wednesday, March 21, 2018, 14:35: Ion gauge on.
Wednesday, March 21, 2018, 14:42: RGA on.
Thursday, March 22, 2018, 06:52: Waterlines opened: Vacuum stable @ 3.04e-07T
Thursday, March 22, 2018, 06:53: Power/sources on.
Thursday, March 22, 2018, 06:56: IV4 Opened.
Device |
Temp
[C] |
Flow
[lpm] |
HS + MSP |
21.9 |
3.61 |
TBHT |
21.6 |
2.80 |
COIL + EE |
21.7 |
4.59 |
TGHT |
22.0 |
5.23 |
Thursday, March 22, 2018, 07:00: Auto ramping TGHT / TBHT to 580 / 200 A @ 2A per min.
Thursday, March 22, 2018, 07:04 : BIAS / EZL / EE @ 30 / 13 / 1.5 kV .
Thursday, March 22, 2018, 07:05: Optics on.
Thursday, March 22, 2018, 11:32: Out gassing noted. TBHT @ 200 A . TGHT @ 472 A. Ramping rate slowed automatically. Vacuum @ 3.03e-06T.
Thursday, March 22, 2018, 14:42: Out gassing continued. TGHT @ 570A. Auto ramping TGHT / TBHT to 580 / 250 A @ undefined rate according to vacuum. Vacuum @ 3.03e-06T
Friday, March 23, 2018, 08:11: Auto ramping TBHT from 250 A to 290 A @ 2A per min. TGHT @ 580 A.
Friday, March 23, 2018, 10:20: Anode @ 100V & 8.5mA.
Friday, March 23, 2018, 10:28: Coil @ 50 A
Friday, March 23, 2018, 10:34: Anode @ 200V & 11 mA.
Friday, March 23, 2018, 13:08: RGA froze. Restart RGA
Sunday, March 25, 2018, 20:34 Vacuum stable @ 4.3e-07T .
Sunday, March 25, 2018, 20:34: TBHT @ 290 A. TGHT @ 580 A.
Sunday, March 25, 2018, 20:34 : Coil @ 50 A ^ 0.5 V
Sunday, March 25, 2018, 20:34 : Increasing Coil to 60 A
Sunday, March 25, 2018, 20:43: Vacuum seemed to increase to 4.4e-07T.
Monday, March 26, 2018, 06:45: Optics on. Vacuum stable @ 4.38e-07T
Fernando
Wednesday, March 28, 2018, 08:31: Optics on. Vacuum stable @ 3.57e-7T
Wednesday, March 28, 2018, 16:2: After increasing the coil current to to 75, A the coil voltage started to show an oscillating behaviour. (see image ttached)
When increased to 80 A the oscillatory behaviour increases. Reducing the current to 65A and then increasing it to 70 A showed a steady behaviour
Thursday, March 29, 2018, 15:51: Ramping down EZL, BIAS, and TGHT for the long weekend
Tuesday, April 03, 2018, 09:14: Vaccum at 1.77e-7T
Tuesday, April 03, 2018, 09:14 : Auto ramping TGHT / TBHT to 550/ 250A @ 2A per min.
Tuesday, April 03, 2018, 09:18 : BIAS / EZL / EE @ 30 / 13 / 1.5 kV
Tuesday, April 03, 2018, 09:23 : Optics on
Wednesday, April 04, 2018, 08:39: Ramping TBHT to 290A @ 2A per min. TGHT remains @ 550 A
Friday, April 6, 2018, afternoon: Due to inconsistencies on EPICS, Carla and I Change the Anode power supply to local in order to monitor the leakage current with a multimeter.
Monday, April 9, 2018, afternoon: TBHT@350A and TGHT@550A
PS went current limited at AnodeBias=300V and show 3A on the PS Screen, the multimeter read the same.
Ramp down to 0 V 0A on PS. PS shows 0.01V
PS goes to limited current even at 2V.
Tuesday, April 10, 2018, 09:10: Problem persists even at lower TBHG (330A).
The output cable was removed and the power power supply seemed to behave better. This could mean that there is a short inside the unit, in the past the anode cable had melted into the cup.
Planning to ramp down the TBHT and see if the behaviour remains. If it does, I would ask to remove the unit for inspection.
Tuesday, April 10, 2018, 09:32 : Ramping down TBHTH to 250A
Tuesday, April 10, 2018, 13:07 : Same behaviour. Cooling procedure started to see if the issue is still present, anf if it does remove unit for inspection
Wednesday, April 11, 2018, 06:44: RGA, power/sources confirmed off. IV4 closed. Ion gauge & turbos off.
Wednesday, April 18, 2018, 13:00: Post use comparison of the coil - A.S
1) Used coil from this FEBIAD = 1.999mΩ ***
2) Unused coil A = 2.421mΩ
3) unused coil B = 2.451mΩ |