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Hi Don,</div>
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Brian and I are looking into the controls safety for the overall detector. Currently, on the 6 supermodule test stand we are using an Omega reading a single RTD at the top of the detector to remove power to the heaters.</div>
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The new LED drivers (adjustable power supplies) have a built-in remote shutoff. We are looking into using that circuit to remove output power from the supply.</div>
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I will set a meeting sometime this month and we can discuss the overall controls safety.</div>
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Marc<br>
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<div id="divRplyFwdMsg" dir="ltr"><font face="Calibri, sans-serif" style="font-size:11pt" color="#000000"><b>From:</b> Donald Jones <jonesdc@jlab.org><br>
<b>Sent:</b> Monday, July 3, 2023 3:58 PM<br>
<b>To:</b> Marc Mcmullen <mcmullen@jlab.org><br>
<b>Cc:</b> dsg-halla_ecal@jlab.org <dsg-halla_ecal@jlab.org><br>
<b>Subject:</b> emergency shutdown for ECal</font>
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Hi Marc,</div>
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I am trying to think through how we (you) will be able to implement the over-temperature shutdown on the ECal heater system. I think you said that the LED driver supplies, replace the relays. My understanding was that you were planning to use an Omega process
controller to shut off the relays in the event of an over-temp condition. Did I understand correctly and do we need to re-introduce them? Here is the layout of the electrical system as planned which has no emergency shutoff relay. We could in principle, connect
the 120 VAC plugs into relays that are powered by the AC mains.</div>
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-Don</div>
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-Don</div>
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Donald Jones</div>
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Hall A/C Staff Scientist</div>
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Jefferson Lab</div>
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