<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
<style type="text/css">
<!--
html{color:#555555;}body{line-height:1.5;font-family:'Trebuchet MS','Helvetica Neue',Arial,Helvetica,sans-serif;font-size:87.5%;}h1{font-size:1.6em;}h2.field-label{display:inline-block;font-size:1em;padding-right:5px;min-width:10em;margin:0.3em;}.problem_report{line-height:1.5;max-width:60em;}fieldset.problem_report.resolved
legend{background-image:url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAACXBIWXMAAA7EAAAOxAGVKw4bAAAAy0lEQVQ4jWP8//8/AyWAiZACd3f3/xYWFrht+f//P1a84t3e/0obff4rbfT5D1GGXR0LuoEr3+/7X3W4n2gvwA0gVSOKAcqbfPGGpImJCU45JgYGBoa7fpsZ22wLSbadgYGBgRE9GrF55Vf2BYbHjx8zYjWB0ljAcAGGExkZ/0MtwuoCggmJEBh4AzBS4pMnT/7fuXOH4dKlSwwnT56EiwcGBv43MDBgMDExYdDX12eQkZGBhAlyiC5YsOA/AwMDUXjLli3/iYoFQgAA+pSxZrXofD0AAAAASUVORK5CYII=);background-repeat:no-repeat;padding-left:18px;}fieldset.problem_report.needs_attention
legend{background-image:url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABAAAAAQCAYAAAAf8/9hAAAABmJLR0QA/wD/AP+gvaeTAAAA9ElEQVR42sWTvUoDQRSFv9wMKWxSBVmzdhZJIwTWv9pyLWxTpbE1kBeJPoLxBazzBgGFKNqlHXAhsITUw1y7sMpmjER0YJrDPWcO556BPzhjYPJjlhfT82LUpxcK6Lo5U0JMgcu56tXy7BQajeBDpkAcAEdz1W6uyrLdYieK2DMmKCArcqczpH/ddc0msy+OkyQJC4h3N0ynx+Q5ALtUNs5q5U+8e+R+VPFi4kjk3NZqd++qUK+TZVnYwSfAOyvejeLXt/2qVG/dYoG1dqseBNco27bs/wXKWhIDB8AhcFLAH4Bn4Al4AUqT7RVC++6mv/JVPwDi3VGzomYvyAAAAABJRU5ErkJggg==);background-repeat:no-repeat;padding-left:18px;}.problem_report div.field-items{display:inline-block;}div.date-vitals p{font-size:87.5%;}a{text-decoration:none;}.Readme a:link,.Readme a:visited,.Readme
a:active{color:red;}
-->
</style>
</head>
<body id="mimemail-body" class="elog-logentry-notify">
<div id="center">
<div id="main">
<style>
<!--/*--><![CDATA[/* ><!--*/
div.field-vitals{
margin: 0.5em 0;
}
div.field-vitals .field-type-taxonomy-term-reference {
margin: 0.1em 0;
}
article.comment {
padding-left: 10px;
}
article.comment.odd {
background-color: #EEEEEE;
}
article.comment.even {
background-color: #DDDDDD;
}
div.node-content.logentry table{
width: auto;
border-collapse: collapse;
border-spacing: 0;
border-width: 1px;
}
div.node-content.logentry th{
border: inherit;
}
div.node-content.logentry blockquote{
background-color: #FFFFFF;
}
div.node-content.logentry caption{
font-size: 1em;
font-weight: normal;
}
table.field-vitals{
margin-top: 1em;
margin-bottom: 1em;
font-size: 87.5%;
}
table.field-vitals th{
vertical-align: middle;
text-align: left;
width: 15%;
padding: 0.1em;
}
table.field-vitals td{
vertical-align: middle;
text-align: left;
width: auto;
padding: 0.1em;
}
table.field-vitals td li {
margin-left: 0;
list-style-type: none;
list-style-image: none;
}
table.downtime {
width: 30em;
margin-bottom: 1em;
border: 1px black dotted;
}
table.downtime th {
text-align: center;
}
table.downtime td {
text-align: center;
}
tr.caption th {
border-bottom: none;
}
table.downtime tfoot{
background-color:#EEEEEE;
}
div.field-name-body{
margin: 1em 0;
font-size: 110%;
}
div.date-vitals p{
margin: .1em 0;
}
article div.ctools-collapsible-container{
margin-left: -5px;
clear: both;
}
#comment-form{
margin-left: 5px;
border: graytext outset medium;
-moz-border-radius: 15px;
border-radius: 15px;
padding: 1em;
}
div.comments-form-box {
margin-top: 2em;
margin-bottom: 5em;
}
h3.comment-title {
/* display: none; */
}
p.author-datetime{
font-weight: bold;
}
/*--><!]]>*/
</style><article id="node-898032" class="node node-logentry contextual-links-region article ia-n clearfix" role="article"><header class="node-header"><h1 class="node-title">
<a href="https://logbooks.jlab.org/entry/3825052" rel="bookmark">Hall B Torus and DBX Nitrogen System</a>
</h1>
</header><div class="contextual-links-wrapper"><ul class="contextual-links"><li><a href="https://logbooks.jlab.org/entry/3825052/edit?destination=email/send">Edit</a></li><li><a href="https://logbooks.jlab.org/entry/3825052/delete?destination=email/send">Delete</a></li></ul></div>
<div class="date-vitals">
<p class="author-datetime">
Lognumber <a href="https://logbooks.jlab.org/entry/3825052" class="lognumber" data-lognumber="3825052">3825052</a>. Submitted by <a href="https://logbooks.jlab.org/user/kashy">kashy</a> on <time datetime="2020-08-11T15:56:10-0400" pubdate="pubdate"><a href="https://logbooks.jlab.org/entries?start_date=1597172170&end_date=1597179370&book=HBLOG&book=HBTORUS&book=CLOG">Tue, 08/11/2020 - 15:56</a></time>. </p>
<table class="field-vitals"><tr><th>Logbooks: </th><td><a href="https://logbooks.jlab.org/book/hblog">HBLOG</a> <a href="https://logbooks.jlab.org/book/hbtorus">HBTORUS</a> <a href="https://logbooks.jlab.org/book/clog">CLOG</a></td></tr><tr><th>Entry Makers: </th><td>Kashy</td></tr></table></div>
<div class="logentry node-content">
<p>During our controls work, I was looking at the cryogenic system. I found that a heater in the LN2 reservoir has been turned on to 30% of full power on ~Jan 9, 2020. There was no record of why in the logbooks and no update of the PID control spreadsheet. The change was done by putting the minimum position for the heater to 30% so I am slowly stepping it back down to 0. </p>
<p>The heater power is 2kW so 30% is 600W or 3g/s of LN2<br />
3g/s is equal to 320 liters/day or 85 gallons/day<br />
Current cost of LN2 is 0.25$/gallon so we were throwing away ~ 20$/day does not sound like much, but since Jan 9 approximately 4600$.</p>
<p>Something to keep in mind!</p>
<p>If the system becomes unstable we may have to review this change, but it worked for years with the heater min at 0...</p>
</div>
<div class="attachment-box">
<div class="image-wrapper"><img view_mode="elog_email" class="image-style-plentybig" src="https://logbooks.jlab.org/files/styles/plentybig/public/2020/08/3825052/Screenshot (85).png" width="960" height="503" alt="" title="Time history back to Jan 9 2020" /></div> </div>
</article> </div>
</div>
</body>
</html>