[Dsg-hallb_magnets] Test and mods in the supercon magnet system in HALL B

[Probir Ghoshal]

Dear All,


As discussed this morning with the DC power below is a summary of what we want to accomplish for the testing on the 16th afternoon (DC power is tied up on 15th and 16th Morning) on both magnets (Torus and solenoid) after replacement of the new firmware from Danpysik. The bench test is successfully test and approved by Onish and Sarin (Onish could you please summarize the best test and document/send it to me).

Following discussion with Nick S this afternoon the following needs to be accomplished by end of the firmware replacement.


1) Verify communications/Interlocks remain intact through EPICs with MPS on control ghosjhpower: Set Slew, Set output, Fast Dump request, local/remote, initiate artificial dump from Liquid level/cryocon.

2) Verify opening the new controlled ramp contact changes set-point as seen on EPICs  MPS GUI readout

3) Repeat above steps with MAINs ON.

4) carryout a low current discharge test 100A, if found satisfactory. Following this needed to try again at medium current ~300A (different slew rate) and validate.

5) Check slew rates are correct using EPICs archive, if all is OK go for full current discharge (P Ghoshal - reluctant) using new controlled ramp contact or prefer to carry out at say 1000A/500 A

for torus/solenoid respectively (if all agrees).


Team for charging the reverse polarity as required by Volker/Ruben.

The Cryo team, Dave/Danny need to support keeping the magnets cold the week starting 22nd to carry the following test on reverse polarity.

As discussed and perceived earlier (during commissioning) that magnets are not at risk except the magnet could lead to a fast dump. Physics need to confirm that that this do not effect or pose any risk to any detectors in the range.


After validated we will need to finalize the best way to implement rewiring the PLC watchdog contacts along with re-locating other interlocks that we want moved to the slow discharge circuit(keeping in mind how to physically separate the chain so when we are troubleshooting in person it is not confusing; i.e. not having fast discharge and slow discharge mixed) .  We also need to update firmware on PLC controllers, both of these will happen after we lose cryo.  We would need to schedule 2-3 days for verification/validation prior to restarting in the Fall.

"Note from Nick S - I am still waiting on the Rockwell escalation team after I submitted all fault logs last Monday.  They have not come up with a root cause yet, if they find some fundamental problem with our application code we will need to account for the time required to make changes and validate them.  As they have been working on it for almost 2 months now I don't suspect that would be the case.  My gut is telling me they will generally suggest some options, my personal hope is that our scheduled firmware upgrade will take care of it. "


Schedule -

  1.  16th Afternoon (Tuesday) - replace and validate the firmware and interlock safety . Resources - DC power: Onish/Sarin/MarkT/Jason, Nick S, Probir G, Denny I (Cryo). To be completed by 16th afternoon or evening.
  2.  Week 22nd (Monday) - Plan to test the magnet on reversing polarity. Resources - Magnet (PG/RF), Nick S, Dave K, Denny I (liaison with Cryo to keep the magnets cold for two weeks after 15th before warm up). Note: Can be done on 17 th through 19th April if cryo cannot support with the change over.


Team -  Ruben F, Nick S, DSG, Dave K, Denny I, Bob Miller, Probir G, Scot S, DC Power (Sarin/Onish/Mark/Jason) please let me know your availability and any schedule that needs to be taken care before. I am looking forward to account  flexibility around the new time accounting system and peoples time schedule.

Upon hearing I will put all in schedule, else I will put a place holder tomorrow in the calendar.


Thanks a lot for your support.


Regards


Probir


(Ruben, Dave, Volker, Jonathan - FYI Please)

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