[Dsg-halld_plc] [New Logentry] Follow-up Re: Inoperative magnetometer reading partially troubleshot

[Timothy Whitlatch]

Thanks Brian. 

What "button" are you referring to? 


Tim Whitlatch 
Hall D Engineer 
Jefferson Lab 
600 KELVIN DR STE 5 
Newport News, VA 23606-4468 
757-269-5087 


From: beng at jlab.org 
To: "Eugene Chudakov" <gen at jlab.org>, "Timothy Whitlatch" <whitey at jlab.org>, "Tom Carstens" <carstens at jlab.org>, "Beni Zihlmann" <zihlmann at jlab.org>, beng at jlab.org, "Scot Spiegel" <spiegel at jlab.org>, "Josh" <jfoyles at jlab.org>, "dsg-halld plc" <dsg-halld_plc at jlab.org> 
Sent: Monday, March 12, 2018 6:10:01 PM 
Subject: [New Logentry] Follow-up Re: Inoperative magnetometer reading partially troubleshot 

Follow-up Re: Inoperative magnetometer reading partially troubleshot 


Lognumber 3544238 . Submitted by beng on Mon, 03/12/2018 - 18:05. Logbooks: 	HDLOG HDSOLENOID 

Entry Makers: 	tlemon, amandah 
References: 	3544206 - Inoperative magnetometer reading partially troubleshot 


We performed the verification step of the calibration procedure for the ADC module, this passed. Since doing this test requires swapping out the terminal block we figured that might have been the problem. 

The cables were swapped one-by-one onto the new terminal block, the PXI was rebooted, still bad B_Field reading. 

Okay, maybe the ADC is bad after all? We swapped that out, now in addition to the B_Field reading being bad the I_Shunt reading got worse (from just slightly negative to -10 A). 

Our first clue! It looks like the offset/slope for the channels is incorrect. Low and behold when logging into the PXI the file was changed around when it went bad. 




I manually changed the file to have the same value from the config file on GitHub (which has never changed [went from an offset of -2.509762 to 0.000553]), but all that did was make it positive instead of negative. So there is still some more troubleshooting to do, but we've made some progress and for sure we should run the PXI calibration function the next time the MPS is powered on to get more realistic offsets. 

Also, since someone probably hit this button when there was some field which is why it's reading bad, maybe this should be moved to somewhere less easy to get to? 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <https://mailman.jlab.org/pipermail/dsg-halld_magnets/attachments/20180313/a9507dd3/attachment-0002.html>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: Capture.PNG
Type: image/png
Size: 90172 bytes
Desc: not available
URL: <https://mailman.jlab.org/pipermail/dsg-halld_magnets/attachments/20180313/a9507dd3/attachment-0002.png>