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2.0 Carlyle Electronic
Module (CEM)
The Carlyle solid-state electronic module
(115v-1-50/60 or 240v-1-50/60) is used for
primary control of the compressor contactor, oil
and economizer line solenoids, and unloader and
Vi coils. It also provides compressor thermal
safety protection.
Temperature control for a screw compressor is
critical. Excessive discharge gas and motor
temperatures can cause premature compressor
failures. Therefore control of these temperatures
is very important. The CEM monitors these
temperatures through the use of the factory-
installed 5K thermistor in the motor windings and
field-installed 5K thermistor on the discharge line.
When either thermistor indicates an overheated
condition, the CEM will energize a liquid injection
valve, sending cool liquid into the motor
compartment. This will lower the temperature to
CEM
Injection
Version
AA2203-4
Discharge
Motor
Unloading
(motor)
Injection
on
off
°F (°C)
°F (°C)
205 (96)
190 (88)
180 (82)
165 (74)
N/A
N/A
an acceptable level. Should the thermistor
continue to register an overheated condition, the
CEM will shut down the compressor. This liquid
injection motor cooling valve (Carlyle P/N
EF28BZ007) (used on all models), must be
added to the economizer line downstream of
the check valve and upstream of each
compressor.
Along with temperature monitoring, the module
will control the startup sequencing of the unloader
coil, Vi coil, oil line solenoid, and economizer
solenoid.
The module has received several changes over
time. The most recent version (AA2203-4)
controls per the parameters listed in the table
below. For information on previous versions,
please contact Carlyle Application Engineering.
Refer to Section 8.6 for specific information on
using the CEM with 05T compressors.
Time
Shutdown
Delay
Temp.
Seconds
°F (°C)
2
230 (110)
2
240 (116)
N/A
220 (104
2
Reset
Reset Time
Temp.
Delay
°F (°C)
Seconds
200 (93)
30
200 (93)
30
N/A
205 (96)
FOR REFERENCE ONLY
INCHES
[millimeters (mm)]
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