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<span style="color: rgb(12, 100, 192);">Hi Marco,</span></div>
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<span style="color: rgb(12, 100, 192);">My answers are inline below:</span><br>
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<div id="divRplyFwdMsg" dir="ltr"><font style="font-size:11pt" face="Calibri, sans-serif" color="#000000"><b>From:</b> Marco Mirazita <Marco.Mirazita@lnf.infn.it><br>
<b>Sent:</b> Friday, June 7, 2019 8:42 AM<br>
<b>To:</b> Tyler Lemon<br>
<b>Cc:</b> dsg-rich<br>
<b>Subject:</b> Re: [Dsg-rich] Follow up to RICH N2 flow loss last night</font>
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<div class="PlainText">Hi Tyler,<br>
thank you for this update and for your intervention.<br>
I have a couple of comments though.<br>
1) Bob says that the N2 valve was off. What does it mean? That someone <br>
manually closed it?</div>
<div class="PlainText"><span style="color: rgb(12, 100, 192);">Yes, someone closed manually closed the valve. I don't know if it was at the RICH N2 panel or someplace else, but the effect was the same that N2 flow was lost to RICH from the main Hall B supply
dewar.</span></div>
<div class="PlainText"><span style="color: rgb(12, 100, 192);"></span><br>
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<div class="PlainText">2) From your analysis, we know that the valve was closed on June 3rd,
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then the backup system came into operation and worked for 3 days, but <br>
we got an alarm only when also the backup system died. It means the N2 <br>
system worked for three days in an unsafe mode without any warning. We <br>
got an alarm only when it was "too late" and the flow dropped to zero.<br>
Fortunately, you, Bob and the jlab crew fixed the problem quickly and <br>
most likely the aerogel didn't suffer any damage, but for the future I <br>
think the alarm should be sent out when the primary system fails, while <br>
the backup must ensure enough time time to fix the problem.</div>
<div class="PlainText"><span style="color: rgb(12, 100, 192);">We plan on implementing an alarm on the N2 backup pressure transducers to let us know when the backup supply is in use.</span></div>
<div class="PlainText"><span style="color: rgb(12, 100, 192);">We'll have to look at the values we saw during the loss of N2 to determine what measurements will be alarmed.</span><br>
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<span style="color: rgb(12, 100, 192);">Best regards,</span></div>
<div class="PlainText"><span style="color: rgb(12, 100, 192);">Tyler</span><br>
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