v. 3.0
Reference guide
Compressor Control Module CM-RC-01
3.0
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4.
Functions
The CM-RC-01 compressor module has a number of built-in functions to protect, diagnose, control
and communicate the status of the compressor.
If the CM-RC-01 is locked due to a faulty situation, an external reset must be performed by either
powering off the device for minimum 5 seconds or sending a reset command on the serial bus. If a
BEST converter is connected, it must be removed during the power-off as the converter will supply
power to the module.
Please see section 9 Alarm system and 11 Trouble shooting for the alarms which CM-RC-01 can
set and how to clear the alarms.
Reset using the serial bus is preferable as this gives better statistical data of compressor
operation without the power-cycle interruptions.
4.1
Control functions
Via the BEST Software, the CM-RC-01 can be configured to take care of control functions.
The CM-RC-01 thereby secures the safe operation of the specific compressor with the selected
refrigerant.
4.1.1
Motor start
The CM-RC-01 has internal timers and relays for correct start-up sequence of the compressor for
different start configurations: DOL
– Direct-On-Line, PW - part winding and Y/Δ - Star-delta.
When power is applied to Relay C input on CN2, a compressor start is performed with the correct
start-up sequence and timing. External timers are not needed.
CM-RC-01 handles start-unloading if this is needed by the compressor model using SU or CRII
valves as illustrated below.
