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[Sphenix-magnet-l] re-learn the old tricks/rules ...

From: Kin Yip <kinyip AT bnl.gov>
To: "sphenix-magnet-l AT lists.bnl.gov" <sphenix-magnet-l AT lists.bnl.gov>
Cc: "ctheisen AT bnl.gov" <ctheisen AT bnl.gov>
Subject: [Sphenix-magnet-l] re-learn the old tricks/rules ...
Date: Wed, 31 Aug 2022 16:53:17 -0400

Hi,

After Chung Ho and Charlie Theisen got the PIXe program running (for quench detection) and Carl Schultheiss' tech short all the channels, the Labview program runs without errors and complaints. Each channel shows small/tiny values of mV in the Labview panel.

Without any real voltage, we tried to "crash" it by setting the threshold to small no. or 0. The nominal threshold is 50 mV. But it never wanted to crash and it seemed wrong at first. After we got Chung to 1008B mezzanine, he helped us trace the logics ... Eventually we found that there is "initial ramp" condition (i.e., < 50 A) that during "initial ramp", it'd not crash no matter what voltage we measure at the voltage taps. ( Because the aliaising filters are not that good at low voltage and 50 A won't hurt the magnet etc. ) Carl forgot about this condition he and Zeynap set 4/5 years ago.

So the quench-detection program definitely seems running and Carl will test further ....

Kin

[Sphenix-magnet-l] re-learn the old tricks/rules ..., Kin Yip, 08/31/2022