BTU XT Micro User manual

Manual CRX-001.2
Copyright BTU Ventilation 2010
XT-Micro
www.btuvent.com

3
FORWARD
The new CRX Control Panel from BTU Ventilation is built from the ground u for the 21st century farm man-
ager. Sim licity of o eration, combined with so histicated controls make this.
STANDARD FEATURES:
• Fresh air door control with 1/10 degree control
• 0-20ma Refrigeration control
• 0-20ma Fan VFD s eed control
• On board real time clock calendar
• 8 external relay out uts
• 5 relay out uts
• Dual Plenum tem erature sensors
• Dual o to isolated RS-485 communication orts
• Flexible heat mode and Set oint ram ing
• Back lighted 2x16 local dis lay
• 5 button keyboard
• Outside and Plenum Humidity sensors
• CO2 sensor
• Central distributed time, outside tem and humidity to multi le anels
OPTIONAL FEATURES:
• Color TPC touch screen interface for u to 10 CRX Bin Controllers.
• TPC touch screen gateway to internet for remote control and olling of data.
• Full internet web interface for 10 Bin Controllers using one RGX embedded web server.
• RGX rovides detailed records for u to 10 CRX anels, using web interface. Direct
download into Excel S readsheet.
• RGX rovides e-mail and text messaging for u to 10 CRX anels.
• SDX multi le fresh air door controller
• VPN web site, look at any number of CRX Bin controllers on one age.
• VPN records without RGX web interface using TPC Touch screen.
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XT-Micro Control Panel 3

Page
CRX Sensors
1.0 Input nd Output Specifications ………………………………………………. 5
Main Components
2.0 CRX Display & Keyboard …...………………………………………………. 6
2.1 Display Sequence …………………………………………………………….. 6
2.2 Parameter Description ………………….……………………………………. 8
CRX Operation nd larm modes
3.0 Operational Modes ……………………………………………………………. 17
3.1 Secondary Modes ……………………………………………………………… 19
CRX Operation
4.0 Outside ir Control …………………………………………………………….. 20
Purge Control
5.0 Purge Modes & Theory ….…………………………………………………… 22
5.1 CO2 Flow Chart .……………………………………………………………….. 24
5.2 Sensor Purge Flow Chart …..………….…………………………………….. 25
5.3 Time Purge Flow Chart .……..……………………………………………….. 26
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XT-Micro Control Panel 4

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XT nalog Inputs:
• Plenum 1 F 2250 ohm
• Plenum 2 F 2250 ohm
• Outside Air F 2250 ohm
• Return F 2250 ohm
• Pile 1 F 2250 ohm
• Pile 2 F 2250 ohm
• Pile 3 F 2250 ohm
• Outside Humid % 4-20mA
• Plenum Humid % 4-20mA
• CO2 m 4-20mA
XT Digital Inputs:
• Fan roving Dry contact
• Cell um roving Dry contact
• Refrigeration Fail Dry contact
• Remote Standby Dry contact
• Low Tem SPDT contact
• Start / Sto Dry contact
CRX Sensors: The CRX anel can acce t a number of different in ut sensors and has 13 one am
out uts. In addition, there are two analog out uts that are 0-20mA or 0-10VDC. The fresh air doors
are controlled by two relay out uts.
XT nalog Outputs:
• Freq Drive 0-20mA / 0-10VDC
• Refrigeration 0-20mA / 0-10VDC
XT Digital Outputs:
• Red light
• Yellow light
• Fan / Green light
• Eva cooling um
• Humidifier um 1
• Heater
• Aux 1
• Cavity heater
• Door o en
• Door close
1.0

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XT-Micro Control Panel 6
2.1
CRX Display & Keyboard
10/22/09 13:10
Refig Ramp
Use u and down arrows to navi-
gate thru the main menu. The left
and right keys are used to access
additional arameters associated
with the main menu.
Programmable parameters are
followed with an *. On any of
these parameters pressing the
ENTER key will activate a cursor
indicating program mode. Press
the up and down arrows to
change the parameter. Use the
left and right keys to move the
cursor on multiple program
screens.
Press the ENTER button when
done to save and esca e from the
rogram mode.
10/22/09 13:10
Refig Ramp
Daily RT 2.6
Version 00.27
Temp SP 65.0*
Plenum 65.6
Return 66.0
Pile 1 66.0
Pile 2 66.0
Pile 3 66.0
Door Pos 0
Ref Out 100
High Dev 5*
Low Dev -5*
Temp SP 65.0
Target 65.0*
Ramp Hrs. 0.1*
Ramp Rt 0.5*
Total RT 340
Clear? N/Y
Unit # 1 *
Plen 1 65.0
Plen 2 65.0
OS Temp 65.0
Start 65.6
OS Hum 49.0
Wetbulb 10.0
OS Diff -1 *
Force? *
Hum SP 95.0*
Plen Hum 95.0
Display Sequence
ENTER
2.0

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XT-Micro Control Panel 7
CO2 SP 2000*
CO2 1240
Fan Spd 75.0
Cool Sp 65.6*
Recir Sp 60.0*
Min Sp 50.0*
Ref Sp 90.0*
Purge Sp 70.0*
Heat Diff -2.0* xH Temp 0.0*
xH Time 0*
Schedule 1
Cooling *
Start 00:00 *
End 24:00 *
Schedule 2
None *
Start 00:00 *
End 24:00 *
Schedule 3
None *
Start 00:00 *
End 24:00 *
Schedule 4
None *
Start 00:00 *
End 24:00 *
High CO2 2400*
Timer 15
Program
PID Values
Cool P 50*
Cool I 10*
Cool D 20*
Cool U 4.0*
Ref P 20*
Ref I 4*
Ref D 10*
Ref U 10.0*
Filter 6*
Program
Timers
Hi Dev 10*
Lo Dev -5*
Fan Fail 1*
Cell Fail 1*
Plen Sen 3*
OS Sen 3*
OS H Sen 3*
High CO2 -5*
Plen Diff 1.5*
Program
Sys Timers
C T 10*
MCR 10*
MRR 30*
Door 180*
Date
11/13/09 *
Time
07:31 *
Program
Hum Timers
On 10*
Off 10*

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XT-Micro Control Panel 8
Program
Miscellaneous
Cell Eff 90*
R S 3*
ux config 3*
Off 20 On 60
Parameter Description
10/22/09 13:10
Refig Ramp
Shows date, time and anel mode of o eration. No rogrammable values. The left side
of the bottom line is the main mode and the right side is the secondary mode.
Daily RT (system run time since noon) 2.6 hrs
Version 00.03 software version 0.03
Daily RT 2.6
Version 00.03
(Programmable Parameter)
Total Run Time in hours for the year. Clear once a year. Choose Yes to clear time.
Total RT 340.0
Clear? N/Y
(Programmable Parameter)
Unit # is the anel number when used in a network with multi le anels. Each anel
must have a unique number.
Unit # 1 *
(Programmable Parameter)
Tem SP (tem erature set oint) This is the desired lenum tem erature set oint. Press
the ENTER button to change the set oint.
Plenum is the current lenum tem erature. The lenum tem erature is the average of
two lenum sensors. The two sensors are located on J7 and J10.
Temp SP 65.0*
Plenum 65.6
Return is the tem erature of the return air and is on terminals 1&2 of J11.
Pile 1 is the tem erature sensor located on ins 3&4 of J15.
Return 66.0
Pile 1 66.0
Pile 2 is the tem erature sensor located on ins 3&4 of terminal J18.
Pile 3 is the tem erature sensor located on ins 1&2 of terminal J18.
Pile 2 66.0
Pile 3 66.0
Door Pos is the osition of the fresh air doors in ercent.
Ref Out is the refrigeration out ut in ercentage.
Door Pos 0
Ref Out 100
2.2
OM Switches Fan
uto *
Refrig Switch
Manual 25%*
Cavity Switch
uto *
Door Switch
uto *
Clima Switch
Off *
Humid Switch
Manual *
Heat
uto *
ux
Off *

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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.

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(Programmable Parameter)
Hum SP (Humidity Set oint) This is referring the desired Plenum Humidity. Press Enter
to change the Hum SP.
The Plen Hum ( lenum humidity) is the actual lenum humidity. Pin 1 of J26 is the le-
num humidity sensor in ut.
Hum SP 95.0*
Plen Hum 95.0
CO2 SP 2000*
CO2 1240
(Programmable Parameter)
CO2 SP (CO2 Set oint) This is the value for the desired CO2 level in the building. The
value is in m. To change the SP ress the ENTER button. CO2 is the actual value of
the building CO2 level in m.
High CO2 2400*
Timer 15
(Programmable Parameter)
High CO2 is an alarm setting. The value is in m and can be changed by ressing the
ENTER button. Use the u and down arrows to change the value.
The alarm has an associated timer. The alarm can be disabled by setting the timer to 0.
The timer is in minutes and the CO2 level would need to be higher than the SP for the
amount of the timer to activate the alarm. Once the alarm is activated the system would
shut down. The timer can also be a soft alarm which means that it will alarm, but not
shut the system down. To set the timer soft, the value must be neg. Exam le: a ten
minute soft alarm would be –10. Press ENTER to change the value and use the u and
down arrows. To go negative, use the down arrow to go ast zero.
Fan Spd 75.0
Cool Sp 65.6*
(Programmable Parameter)
Fan S d (Fan s eed in %) Fan S d is the current fan s eed in ercent.
Cool S is the cooling set oint for the fans when the system in in the Cooling mode. The
Cool S is rogrammable by ressing the ENTER button.
Recir Sp 45.0*
Min Sp 20.0*
(Programmable Parameter)
Recir S (Recirculation Set oint %) Recir S is the Fan s eed set oint when the system
is running in the Recirculation mode. Recir S is rogrammable by ressing the ENTER
button.
Min S (Minimum Set oint %) is the minimum ercent the fans can run at if being con-
trolled by the ile differential.

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(Programmable Parameter)
Ref S (Refrigeration Set oint %) Ref S is the s eed in ercent that the fans will run
when the system is in the Refrigeration mode. Ref S is a rogrammable arameter.
Press ENTER to change.
Purge S is the s eed in ercent that the fans will run when the system is in a Purge.
This is a rogrammable arameter. Press Enter and then use the right arrow to get the
cursor in the lower line.
Ref Sp 75.0*
Purge Sp 100*
Heat Diff 0.5*
xH Temp 50*
xH Time 10*
(Programmable Parameter)
Heat Diff (Heat Differential) The Heat Diff is used when the lenum tem erature dro s
below the tem erature Set oint. If the lenum is less than SP - Heat Diff then the return
air heater will turn on. This is a rogrammable arameter and can be changed by ress-
ing ENTER. This value is a ositive number.
(Programmable Parameter)
AxH Tem (auxiliary heat) The AxH Tem is a set oint of aux heat. The heat could be
located any where in the storage and would be connect to the Aux out ut. The Aux 1
config byte needs to be set to 5 for this to work. If the outside air tem erature dro s be-
low the AxH Tem setting the Aux 1 out ut would turn on.
This has an associated timer AxH Time. The outside air needs to be below the AxH
Tem for the amount of time rogrammed. The AxH Tem can be rogrammed by
ressing the ENTER. Press the right arrow to move the cursor to the AxH Time.

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(Programmable Parameter)
Schedule 1 The CRX has four different schedulers that can be used to setu the desired
o eration of the anel. Each scheduler has six ossible modes.
1 None - the scheduler is disabled
2 Cooling - during the scheduled time the system would run in cooling if cooling air
was available.
3 Recirc (Recirculation) - during the scheduled time the system fans would reticulate
the air with the fresh air doors closed.
4 Refrigeration - during the scheduled time the system would run in Cooling if cooling
air was available. If cooling air was not available then the system would run in Re-
frigeration.
5 Rerfrig Only (Refrigeration Only) - during the scheduled time the system would run
in refrigeration only.
6 Purge - during the scheduled time the system would run a urge cycle.
To change the schedule mode, ress the ENTER key and use the u and down keys to
change the mode.
Schedule 1
Cooling *
Start 00:00 *
Stop 24:00 *
(Programmable Parameter)
Start (Schedule 1) This is the start time for schedule 1 in military 24 hour time. Set for
the desire start time. 00:00 is midnight. Press the ENTER button to rogram the Start
time.
Sto (Schedule 1) This is the sto time for schedule 1 in military 24 hour time. Set for
the desired sto time. Press ENTER to go into the rogram mode, use the right arrow to
Schedule 2
Recirc *
Start 23:00 *
Stop 02:00 *
(Programmable Parameter)
Schedule 2 has riority over Schedule 1. In the above exam le Schedule 1 is set to run
cooling 24 hours a day. Schedule 2 is set for the Recirc mode. This will have riority
over the Schedule 1 setting. Press the ENTER key to change the Schedule 2 mode.
(Programmable Parameter)
Start (Schedule 1) This exam le shows the Schedule 2 to Start at 23:00 or 11 m and
Sto at 02:00 or 2am. Thus the system would switch from Cooling to Recirc for this time
eriod. Press ENTER and use the right key to lace the cursor at the desired arameter
to be changed.
Schedule 3
None *
Start 00:00 *
Stop 24:00 *
(Programmable Parameter)
Schedule 3 has riority over Schedule 1 & 2.
(Programmable Parameter)
Set the desired Start and Sto times for Schedule 3.
Schedule 4
None *
Start 00:00 *
Stop 24:00 *
(Programmable Parameter)
Schedule 4 has riority over Schedule 1,2 & 3.
(Programmable Parameter)
Set the desired Start and Sto times for Schedule 4.

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(Programmable Parameter)
The PID values control the ways that the fresh air doors and refrigeration control tem-
erature. Press the right key to access the PID values for cooling and refrigeration.
Program
PID Values
Cool P 50*
Cool I 10*
Cool D 20*
Cool U 4.0*
Ref P 20*
Ref I 4*
Filter 6*
(Programmable Parameter)
Cool P (Cooling ro ortional gain) The default value is 30, increasing this value will
cause the overall system erformance to be come faster. P is most effective on sudden
changes.
Cool I (Cooling integral gain) The default value is 8. The integral gain roduces an error
based on small errors over time. Increasing this value will cause the small error to be
am lified over time and the system to be more sensitive to static errors.
(Programmable Parameter)
Cool D (Cooling derivative gain) The derivative is roduced by a sudden change in the
error. If the tem erature is several degrees above set oint, the PID will ram quickly.
The error may not change much until the door reaches a given osition. At this oint the
tem erature would dro quickly. The derivative acts like a brake and will offset the error
when large changes are being made. If the tem erature over shoots at start u , you
would want to increase the Derivative. The default setting is 20.
Cool U (Cooling u date time) This value is in 1/10’s of a second and determines when
the PID loo is u dated. The default value is 100. Increasing this value will slow down
the entire loo , decreasing will cause the loo and res onse to s eed u .
(Programmable Parameter)
Ref P (Refrigeration ro ortional gain) The default value is 20, increasing this value will
cause the overall refrigeration system erformance to be come faster. P is most effective
on sudden changes.
Ref I (Refrigeration integral gain) The default value is 4. The integral gain roduces an
error based on small errors over time. Increasing this value will cause the small error to
be am lified over time and the system to be more sensitive to static errors.
Ref D 10*
Ref U 10.0*
(Programmable Parameter)
Ref D (Refrigeration derivative gain) The derivative is roduced by a sudden change in
the error. If the tem erature is several degrees above set oint, the PID will ram quickly.
The error may not change much until the refrigeration reaches a given osition. At this
oint the tem erature would dro quickly. The derivative acts like a brake and will offset
the error when large changes are being made. If the tem erature over shoots at start u ,
you would want to increase the Derivative. The default setting is 20.
Ref U (Refrigeration u date time) This value is in 1/10’s of a second and determines
when the PID loo is u dated. The default value is 100. Increasing this value will slow
down the entire loo , decreasing will cause the loo and res onse to s eed u .
(Programmable Parameter)
The filter is a vale from 1 to 10. This number will weight the analog values for all the tem-
eratures, humidity and CO2 readings. The default value is 6, increasing this value will
cause the readings to be more highly filtered and slower to change.

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XT-Micro Control Panel 14
(Programmable Parameter)
The Program Timers are a grou of timers that control all the alarms. A setting of zero
will disable the alarm. A ositive setting in the timer will cause the alarm to shut the sys-
tem down. A negative setting in the alarm will cause the system to alarm, but not shut
the system down. All timers are in minutes. A neg number is still in minutes.
Program
Timers
Hi Dev 10*
Lo Dev 5*
Fan Fail 1*
Cell Fail 1*
Plen Sen 3*
OS Sen 3*
OS H Sen 3*
High CO2 -5*
Plen Diff 1.5*
(Programmable Parameter)
Hi Dev (High Deviation Timer) The Hi Dev timer is a count down timer and will alarm if
the alarm conditions remains for the duration of the timer. If the alarm condition clears
art way thru the timer count down, the timer will reset. Press ENTER to change the
timer. The timer is in minutes.
Low Dev (Low Deviation Timer) The Low Dev timer is a count down timer and will alarm
if the alarm conditions remains for the duration of the timer. If the alarm condition clears
art way thru the timer count down, the timer will reset. Press ENTER and then use the
right key to move the cursor to the bottom line to change the timer. The timer is in min-
utes.
(Programmable Parameter)
Fan Fail (Fan Fail Timer) This is a count down timer that starts when the fan is given a
signal to start. If the fan fails to start before the time counts down a alarm will be trig-
gered. Press ENTER to rogram the timer. Timer is in minutes.
Cell Fail (Eva orative Cooling um fail timer) This is a count down timer that starts
when the cell um is given the signal to start. If the um fails to start before the time
counts down a alarm will be triggered. Press ENTER and use the right key to move the
cursor to the bottom line. Timer is in minutes. Both timers can be ositive, negative or
shut off when set to zero.
(Programmable Parameter)
Plen Sen (Plenum Sensor Fail Timer) This is a count down timer that will start when
either of the lenum sensors are determined to be out of range. The out of range can be
caused by either a short or o en circuit in the wiring. The timer is in minutes and can be
rogrammed by ressing the ENTER key.
OSA Sen (Outside air Sensor Fail Timer) This is a count down timer that will start when
the outside air sensor is determined to be out of range. The timer is in minutes and can
be rogrammed by ressing the ENTER key. Both timers can be ositive, negative or
shut off when set to zero.
(Programmable Parameter)
OSA H Sen (Outside Humidity Sensor Fail Timer) This is a count down timer that will
start when the outside humidity sensor is determined to be out of range. The timer is in
minutes and can be rogrammed by ressing the ENTER key.
High CO2 (High CO2 level Timer) This is a count down timer that will be activated when
the CO2 level is greater than the High CO2 setting. The timer is in minutes and can be
rogrammed by ressing the ENTER key and using the right key to osition the cursor.
(Programmable Parameter)
Plen Diff (Plenum Difference Timer) This is a count down timer that will start when the
difference in tem erature between the two lenum readings are greater than the Plen
Diff. The timer is in minutes and can be set by ressing the ENTER key.

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XT-Micro Control Panel 15
Program System Timers: This is a set of timers that are used in the controls rimary to
kee the system from short cycling. These timers are only zero or ositive numbers.
Program
Sys Timers
C T 10*
MCR 10*
MRR 30*
Door 180*
Date
11/13/09 *
Time
07:31 *
(Programmable Parameter)
CAT (Cooling Air Available Timer) When the mode changes from Cooling to Standby,
this timer will be active. The setting will force the mode to stay in Standby until this
amount of time ela ses. This is to revent short cycling when OSA cooling is marginal.
The timer is in minutes. Press the ENTER key to change.
MCR (Minimum Cooling Run Timer) This variable is in minutes and will guarantee that
once you go into the Cooling mode, you will stay in this mode for a minimum run time
and not short cycle. Ty ical settings would be from 15 to 30 minutes. Press the ENTER
key and then use the right key to move the cursor to the lower line to make a change.
(Programmable Parameter)
MRR (Minimum Refrigeration Run) This setting will allow the refrigeration to run for a
minimum time, regardless of cooling air availability. Default setting is 30 minutes. Press
the ENTER key to make changes.
Door (Door O en Time) This time in seconds will determine the door osition. This
value is determined by timing the door o en cycle and door closed cycle. The two values
should be averaged. The default setting is 180 seconds. This is only used when the ram
otentiometer is not available. Press ENTER key and use the right key to osition the
cursor to bottom line to make changes.
(Programmable Parameter)
Date (Calendar Date) This allows the date to be set. Press the ENTER key and then
use the u and down arrows to make the change. Use the left and right keys to osition
the cursor. Press ENTER when done.
(Programmable Parameter)
Time (Clock Time 24hr) Press the ENTER key and then use the u and down arrows to
make changes. Use the left and right keys to osition the cursor. Press ENTER when
done.
Program
Hum Timers
On 10*
Off 10*
Hum Timers (Humidity Timers) This gives access to the rogrammable timers for turn-
ing the Humidifier on and off. Press the right key to go to the timer screen.
(Programmable Parameter)
On (Humidity On Timer) This is the time in seconds that the humidifier will ulse on
when the fans are running. The humidifier will then be off for the rogrammed amount of
time and then back to the On time. Press ENTER to rogram. Max value is 250 sec-
onds.
OFF (Humidity Off Timer) This is the time in seconds that the humidifier will ulse off
when the fans are running. The humidifier will be off for this amount of time and then will
ulse on for the On Timer setting. Press ENTER to rogram and then use the right arrow
to osition the cursor. Max value is 250 seconds.

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XT-Micro Control Panel 16
Program Miscellaneous: This allows access to a number of miscellaneous arameters.
Press the right key to access.
Program
Miscellaneous
Cell Eff 90*
R S 3*
Refrig Switch
uto *
Cavity Switch
uto *
Door Switch
uto *
(Programmable Parameter)
Cell Eff (Eva orative Cooling Efficiency) The efficiency of different eva orative cooling
cells can vary greatly de ending on a number of variables. Cell Eff allows you to set the
efficiency of a given eva orative cooling system. This can be determined by setting the
cell to 100 ercent and watching in on a good warm dry day. The setting is from 0 to 100
ercent.
RAS (Rise Above Set oint) This value is what terminates the Cooling air available sig-
nal. The RAS is in 1/10 of a degree. A setting of 3 would be .3 degrees above set oint.
If the Plenum tem erature gets above the RAS setting and the outside air is above the
Start tem erature then the Cooling mode will be terminated. Press the ENTER key to
change the RAS arameter.
Refrig Switch (Refrigeration Switch) The switch has three ositions, Off, Manual and
Auto. Off will revent the refrigeration from starting. Manual osition will all the desired
out ut ercentage to be entered. Used the u and down arrows to change the ercent-
age. When done testing make sure to go back to Auto or Off. The Auto osition will al-
low the controller to turn the refrigeration on and off. Press ENTER to change the osi-
tion.
Cavity Switch: The switch has three ositions, Off, Manual and Auto. This switch con-
trols the out ut for the cavity heater. Off, Manual and Auto. Off will revent the cavity
heat from turning on. Manual will turn the cavity heat on all the time. Auto will allow the
rogram to turn the cavity heat on and off.
Door Switch: The door switch has three ositions. This enables the doors to be shut off
or controlled in manual or auto. In manual the doors can be o ened or closed using the
u and down keys. Pres the ENTER button to change the mode. If in manual, remem-
ber when done testing to switch back to auto.
OM Switches Auto-Off-Manual Switches. These are software switches that can be changed remotely.
For these switches to work the actual hardware switch on the board needs to be in the
Auto osition.
Fan Switch
uto *
Programmable Parameter)
The Fan Switch has three modes. Off, Manual and Auto. In off the Fans will not run re-
gardless of the Sto / Start switch osition. In Manual the Fans will run when ever the
Sto / Start switch is in the Start osition. In auto the controller will turn the fans on and
off as long as the Sto / Start switch is in the Start osition.

17
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XT-Micro Control Panel 17
Heat Switch
uto *
ux Switch
Off *
The Heat Switch has three ositions, Off, Manual and Auto. In the off osition the heat
will not turn on. In the Manual osition the return air heat will be on all the time the Sto /
Start switch is in Start. In the Auto osition the return air heat will turn on and off when
needed. This is a rogrammable function and can be changed by ressing the Enter
button.
Aux Switch. The Aux switch can be used for any ty e of addition control. It has three
ositions, Off, Manual and Auto. In the off osition the Aux out ut will not turn on. In the
manual osition the Aux out ut will turn on any time the Sto / Start switch is in the Start
osition. In Auto the Aux switch will turn on and off when needed. To change ress the
Enter button.
Climacell
Man *
Climacell is the BTU name for the eva orative cooling cell. This screen shows the status
of the cell. The Cell can be off, auto or manual. In manual the cell will run any time the
fans are running. In off, the cell will not run. In auto the cell can be used to control hu-
midity. To change modes, ress the ENTER button and use the u and down arrows to
change the mode.
Humidity
uto *
Humidity refers to the Hum 1 out ut. This is used to turn on and off the water um for
the humidifier. The s inner will run all the time. The Hum 1 out ut has three modes.
Off, Auto and Manual. In Off the humidifier will not run at all. In Manual the humidifier
will run when ever the fans are on. In Auto the Hum 1 out ut will go on and off to main-
tain lenum humidity. To change modes, ress the ENTER button and use the u and
down arrows to change the mode.

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XT-Micro Control Panel 18
CRX Modes: The XT Panel o erates in two modes: the main o eration mode and a secondary mode. De-
ending on the setu of the alarms, it is ossible to continue running in an alarm mode.
For exam le, for a cell um failure, the secondary mode would indicate a cell um failure, send out the alarm,
indicate an alarm (a blinking red light) but continue to run in Cooling or Refrigeration. Wetbulb calculation would
be shut off.
3.0 CRX Modes of Operation
Main Operation Modes:
Shutdown: Shutdown is activated by the Sto /Start switch set to the Sto osition.
Standby: Standby can only be activated with the time clock set to standby or
with no outside cooling available during Cooling mode.
Cooling: Cooling mode can only be activated with outside cooling air available
and time clock set to either Cooling or Refrigeration mode.
Refrig: Refrigeration mode will be activated when cooling air is not available
and the time clock is set for Run or Ref Only.
Recirc Recirc will be activated when the time clock is set to Recirc, there
is no outside cooling air available and the refrigeration switch is set to
Off.
Remote Stop: Remote sto is activated with the Sto button from either the HMI
touch screen or web interface.
Low Temp: The low tem alarm is triggered by the backu low tem safety
thermostat. It can only be reset with the Start/Sto switch.
Parameter Fail: The Parameter fail is triggered by an out-of-range setting on one of the
critical arameters. If set oint is < 32.0 or > 76.7, the alarm is trig-
gered. If target is < 32.0 or > 76.7, the alarm is triggered. If ile diff
selection > 8, the alarm is triggered. If Start differential > 50 or < -50,
the alarm is triggered.
Remote Standby: Remote Standby is activated by a contact closure across in ut IN4.
Ty ically used for off- eak ower, ri le control or refrig defrost.
larm Standby: Any alarm condition that was set to shut down the system.
Fan Fail: The fan in ut IN1 did not get a closed contact within the fan fail timer
eriod. There is a rogrammable timer associated with this alarm.
Cooling / Purge: The system is in Cooling and the return air heaters are being used to
force the fresh air doors o en. This cycle has been triggered by time
and not the CO2 sensor.
Refrig / Purge: The system is in Refrigeration and the fresh air doors are o en to the
max door setting. This cycle has been triggered by time and not the

19
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XT-Micro Control Panel 19
Timed / Purge: The system is in Timed and the time urge cycle is active. At the
designated time, the fresh air door will o en to the max door setting
and urge for the rogrammed time. This cycle has been triggered by
time and not the CO2 sensor.
Cooling / CO2: The system is in Cooling and the CO
2
level is above The CO2 set oint.
The return air heaters are active to hel o en the doors and urge the
CO
2
.
Refrig / CO2: The system is in Refrigeration and the CO
2
level is above CO2 set oint.
The fresh air doors are being used to urge the CO
2
.
Heat: This mode is used to turn on return air heaters when the system is
running in Cooling, the doors are closed and the lenum tem erature
has dro below the Set oint minus the heat differential.

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XT-Micro Control Panel 20
Secondary Modes:
None: There are no secondary modes currently active.
Ramp: The set oint and target are different values and the system is in the
Ram mode. The Ram mode can ram the set oint u or down.
Cell Pump Fail: The Cell Pum Fail will trigger when the cell MOA switch is turned to
Auto and the Cell um in ut (IN2) is off. There is a rogrammable
delay timer (CPF_timer) associated with this alarm..
Refrig Fail: The Refrig Fail Alarm will trigger when the refrigeration MOA switch is
turned to Auto, the refrigeration in ut (IN3) is off and the system is in
Refrigeration mode. The system will continue to run in Cooling mode if
outside cooling is available.
Plen Sensor Fail: The Plenum Sensor Fail alarm is triggered by a rogrammable differ-
ence between Plen 1 and Plen 2. There is a rogrammable timer
Associated with this alarm.
OS Sensor Fail: The Outside Air Sensor Fail alarm is triggered by an out-of-range out-
side air sensor. There is a rogrammable timer associated with this
alarm.
Low Dev: The Low Dev alarm will trigger when the lenum tem erature dro s
below the low dev setting, the timer has ex ired and the fans are run-
ning. There is a rogrammable timer associated with this alarm.
High Dev: The High Dev alarm will trigger when the lenum tem erature rises
above the high dev setting, the timer has ex ired and the fans are
running. There is a rogrammable timer associated with this alarm.
OSH Sensor Fail: The Outside Humidity Sensor Fail alarm is triggered by a out-of-range
outside humidity sensor. There is a rogrammable timer
associated with this alarm.
Low Humidity: The Low Humidity alarm is triggered when the lenum humidity level
dro s below the low humidity setting. The system must be in a valid
o erating mode. There is a rogrammable timer associated with this
alarm.
High CO2: The High CO
2
alarm is triggered by a CO
2
level greater than the high
CO
2
setting. The system must be in a valid o erating mode. There is a
rogrammable timer associated with this alarm.
3.1