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Hi Brian,</div>
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Thanks for this. Yes it is definitely important to reset the MPS comms as soon as possible. If the system tries to initiate a controlled ramp down while communication is lost the PLC will notice it is not progressing as it should and would initiate the MPS
ramp down. Once initiated we cannot recover until back to 0 amps again.</div>
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having looked at the MPS comm reset it is in the 'initialize' sub routine that we reset the current setpoint to 0 amps, we can easily comment out this portion at the next opportunity.
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-Nick<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Dsg-hallb_magnets <dsg-hallb_magnets-bounces@jlab.org> on behalf of Brian Eng <beng@jlab.org><br>
<b>Sent:</b> Friday, August 7, 2020 11:25 AM<br>
<b>To:</b> dsg-hallb magnets <dsg-hallb_magnets@jlab.org><br>
<b>Subject:</b> [Dsg-hallb_magnets] MPS Comm Alarm</font>
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<span style="color:rgb(0,0,0); font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">Figured I'd post to the mailing list and get input rather than posting to the entries themselves; regarding the logentries related to this: </span><a href="https://logbooks.jlab.org/entry/3821968" id="LPlnk464765" style="font-family:Calibri,Arial,Helvetica,sans-serif; font-size:12pt">https://logbooks.jlab.org/entry/3821968</a><br>
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If this particular alarm comes up again it probably would it be better to reset it as soon as possible?</div>
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While nothing is in danger we end up losing most of the software controls when the PLC can't talk with the power supply. Instead it's mostly hardware protection, fortunately during the last long break a lot of faults got moved to a slow dump in hardware, but
best to not let it get that far.</div>
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The only reason I'd hesitate to make that the SOP is that is as Eugene noted it started to ramp down after resetting, which isn't very surprising. Any suggestions?</div>
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