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Entry  Mon Aug 11 00:58:31 2008, rana, Update, PEM, 2 years of temperature trend Untitled.png
    Reply  Mon Aug 11 09:39:29 2008, rana, Update, PEM, 2 years of temperature trend 
Message ID: 820     Entry time: Mon Aug 11 00:58:31 2008     Reply to this: 821
Author: rana 
Type: Update 
Category: PEM 
Subject: 2 years of temperature trend 
The PSL RMTEMP alarmed again because it says the room temperature is 19.5 C. Steve said in
an earlier log entry that this is a false alarm but he didn't say why he thought so...

I say that either the calibration of the RMTEMP channel has drifted, the setpoint of the HVAC
has shifted, or there's a drift in the RMTEMP channel. I don't know what electronics exactly
are used for this channel so not sure if its susceptible to so much drift.

However, since the Dust Monitor (count_temp) shows a similar temperature decline in the
last two years I am inclined to blame the HVAC system.

The attached plot shows 2 years of hour-mean trend.
Attachment 1: Untitled.png  18 kB  Uploaded Mon Aug 11 02:09:40 2008  | Hide | Hide all
Untitled.png
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