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XT-Micro Control Panel 9
The CRX uses two lenum tem erature sensors. Plen 1 is the tem erature sensor on
ins 2&3 of J7. Plen 2 is the tem erature sensor on ins 2&3 of J10. These two sensors
are averaged and dis lay on the main screen as Plenum.
Plen 1 65.0
Plen 2 65.0
(Programmable Parameter)
High Dev (High Deviation) is an alarm setting. If the lenum tem erature exceeds the
tem erature Set oint lus High Dev a High Deviation alarm will be activated. Press the
ENTER button to change the High Dev setting.
Low Dev (Low Deviation) is an alarm setting. If the lenum tem erature is less than the
tem erature Set oint minus the Low Dev a Low Deviation alarm will be activated. To
rogram the Low Dev setting Press the ENTER button and then ress the right button to
osition cursor. Make changes using u and down buttons and then ress ENTER.
High Dev 5*
Low Dev -5*
Temp SP 65.0
Target 65.0*
(Programmable Parameter)
This screen is for setting u the Set oint Ram function. The Target is the desired tem-
erature setting. The system can ram down and ram u . Exam le: the current Tem-
erature Set oint is 65.0 and the final desired storage tem erature is 45.0. Set the Tar-
get to 45.0 and the system will start to gradually ram the tem erature Set oint down to
45.0. Press the ENTER button to change the Target. The Target can be set above the
Set oint for warming and ram ing u or below the Set oint for ram ing down. To turn
the ramp function off, set the Target the same as the Temp SP.
Ramp Hrs. 24*
Ramp Rt 0.1*
(Programmable Parameter)
This screen is art of the Set oint Ram function. The Ram Hrs is the number of hours
the system will run before it makes a Set oint change. Once the system has run the
Ram Hrs the Set oint will be incremented or decremented by the Ram Rate. A ty ical
setting is .1 degrees.
OS Temp 65.0
Start 65.6
This screen shows when Cooling air will be available. Any time the OSA (outside air
tem erature) is less than the Start, Cooling air is available. See the section on outside
air control for the Start calculation.
OS Hum 49.0
Wetbulb 10.0
OSA Hum (outside humidity) Current outside humidity.
The Wetbulb is the wetbulb de ression in degrees. At 100 ercent saturation, the Wet-
bulb is the number of degrees of cooling available with the current outside tem erature.
OS Diff -1 *
Force? *
(Programmable Parameter)
OSA Diff (outside air differential) This is used to offset the Start tem erature. It can be
set lus or minus and is normally defaulted to –1. With no eva orative cooling the Start
tem erature would be Set oint minus the OSA Diff. To rogram ress the ENTER but-
ton.
Force? (force cooling or force refrigeration). This is a rogrammable arameter that al-
lows the o erator to force the system into cooling or refrigeration regardless of the out-
side air tem erature. When forced the system will start, o en the doors and run for the
MCR (minimum cooling run) timer or MRR (minimum refrigeration run). Press ENTER,
then use the right arrow to get the cursor to Force. Use the u and down arrows to acti-
vate the Force Cooling or Force Refrigeration.
