[Hallb-solenoid] clarification comparator procedures for interlock cheout list

[Nicholas Sandoval]

Hi Pablo,

1.
As you have read through the document you know you have already tested the PLC Software Quench 2nd Threshold which leads to the PLC Fast Dump, starting on page 9
At the time of the Power Up ERR we used the terms Fast Ramp Down and Controlled Ramp down interchangeably.  Please redline through the second set of comparator test and change the "Fast Ramp Down" with "Controlled Ramp Down"

Additionally, please redline the second line under "software quench 1st threshold controlled ramp down" which says: "Disable the PLC QD fast ramp down by temporarily..." Change it to : "Disable the PLC QD 2nd Threshold by temporarily..."  

2.


Please redline the step "Verify the dump contactor open" for comparator 7-10

As you are aware, at the moment we do not have the magnet set at a low current to verify it actually goes into a controlled ramp.  So for the purposes of this test all 1st Threshold software QD comparators will result in a fast dump via ramp down monitor failure that was initiated from the software QD first threshold tag.  

Once the magnet has been commissioned we will be able to perform the checklist in a manner which allows full checkout of the controlled ramp down.   Fortunately we have the ramp down monitor which will always lead to the fast dump.

Thanks and Best Regards,

Nick


----- Original Message -----
From: "Pablo Campero Rojas" <campero at jlab.org>
To: "Nicholas Sandoval" <sandoval at jlab.org>
Cc: hallb-solenoid at jlab.org
Sent: Wednesday, October 5, 2016 4:18:25 PM
Subject: clarification comparator procedures for interlock cheout list

Hello Nick, 

We need some clarifications on the interlock checkout procedure: 

1.for the tasks in page 14 called "software quench 1st threshold Controlled ramp down" and the following comparator tests; the procedure says "Disable the PLC QD fast ramp down by temporarily raising the thresholds to 250 mV"; under that for each comparator procedure it says " Verify the Fast Ramp Down was initiate" Should it be Verify the controlled Ramp Down was initiate? 

2. On page 16 for comparator 7,8,9 and 10 there is a step added (Verify the dump contactor open) that is not in the procedure for the comparator 1 through 6. Should this extra step be skipped? 

Please let us know about this clarifications, as they are preventing the completion of this tasks , thanks. 

Pablo Campero