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CSR-20 & CSR-40, September 1999
Unit Controls
Unit Control Box
1.
ON/OFF SWITCH.
a.
ON position. Unit will operate on cool or heat
depending on the controller setpoint temperature and
the container air temperature.
b.
OFF position. The unit will not operate.
µµ
P-D Controller
The Thermoguard
®
µ
P-D microprocessor controls all unit
functions to maintain the cargo at the proper temperature. The
controller also monitors and records system faults, limits
power demand and performs pre-trip.
Ten touch sensitive keys are used to display information,
change the setpoint, change the programmable features and
initiate control tasks.
1.
SELECT KEY. Press this key to enter and display
screens from the controller menu.
2.
UP KEY. Press this key to increase the setpoint (and
other settings in the menu), and scroll UP through the
menu display.
3.
DOWN KEY. Press this key to decrease the setpoint (and
other settings in the menu), and scroll DOWN through the
menu display.
4.
ENTER KEY. Press this key to load the setpoint (or other
setting in the menu), and execute other controller tasks.
5.
C/F KEY. Press this key to view temperatures in the con-
troller display in the alternate temperature scale.
Alternate display shows while the key is pressed.
NOTE: The C/F units shown on the controller
display can be changed by pressing and hold-
ing the C/F key, and then pressing the ENTER
key.
6.
RET/SUP KEY. Press this key to view the alternate sen-
sor temperature (non-controlling sensor) in the controller
display. Alternate display shows while the key is pressed.
7.
DEFROST KEY. Press this key to prepare the controller
to initiate a manual defrost cycle. Then press the ENTER
key to LOAD a manual defrost. If the evaporator coil
temperature is below 10 C (50 F), the unit will defrost.
Otherwise the controller will display “DFRST INVAL”
and the unit will continue normal operation.
8.
PRETRIP KEY. Press this key to prepare the controller to
initiate an automatic Full Pretrip test. Then press the
ENTER key to LOAD a pretrip test. The controller will
perform a Full Pretrip test if no alarms are present.
9.
SOT KEY. Press this key to prepare to place a Start of
Trip marker in the datalogger. Then press the ENTER
key to LOAD the Start of Trip marker.
10. ALARM KEY. Press this key to display alarm codes
when the Alarm LED is lit (or flashing). Press the
DOWN arrow key to view additional alarm codes that
may be present. After viewing, writing down and correct-
ing all alarm conditions, press the ENTER key to clear
alarms.
Other Unit Controls
1.
WATER PRESSURE SWITCH (OPTION). When water
pressure greater than 117 +/- 21, 1.17 +/- 0.21 bar, 17 +/-
3 psig is provided to the condenser-receiver tank, the
water pressure switch opens. This causes the controller to
stop condenser fan operation. When the water pressure
decreases below 35 +/- 21 kPa, 0.35 +/- 0.21 bar, 5 +/- 3
psig, the switch closes, causing the controller to place the
unit on air-cooled condenser fan operation.
NOTE: Water-cooled condenser operation
requires a water flow of 19 to 38 l/min. (5 to 10
gal./min.).
3
Operating Instructions