Bitzer CM-RC-01 User manual

Reference guide
Compressor Control Module
CM-RC-01
Compressor Control Module

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Content
1. Read this first! 4
1.1 Reference guide 5
1.2 Safety 5
2. General 6
3. Definitions 7
4. Functions 8
4.1 Control functions 8
4.1.1 Motor start 8
4.1.2 Oil heater 9
4.1.3 Cylinder head and motor cooling 9
4.1.4 Capacity control 10
4.2 Monitoring and diagnosis 10
4.2.1 Motor temperature 10
4.2.2 Discharge temperature 11
4.2.3 Oil supply 11
4.2.4 High pressure handling 11
4.2.5 Pressure limits (option) 11
4.2.6 Application limits (option) 12
4.2.7 Short-cycling warning 13
4.3 Datalog 13
4.3.1 Alarms 14
4.3.2 Events 14
4.3.3 Datalog information 14
4.3.4 Periodic data 14
4.3.5 Statistics and counters 14
4.3.6 Accumulated operation counters 15
4.3.7 Capacity load 15
4.3.8 Daily counters 15
4.3.9 Runtime statistic 15
4.3.10 Compressor start statistic 15
4.4 BEST software 16
4.5 Communication 16
5. Control of the CM-RC-01 17
5.1 Commands and setpoint 17
5.1.1 Command Start 17
5.1.2 Setpoint –and speed changes 17
5.2 Enable serial control 18
5.3 Required signals to start the compressor 18
5.3.1 Digital and analogue signals 18
5.3.2 Serial control (Modbus) 18
5.4 Control Word bit definitions 18
5.4.1 Data valid bit 19
5.5 Examples of Serial Control Word setups: 19
5.6 Status Word bit definitions 19
5.7 Setting the serial setpoint 20
5.8 Serial Control Timeout Function 20
6. I/O List for CM-RC-01 21
7. Drawings 23
8. Standards 24
9. Alarm system 25
9.1 Alarm severity types 25
9.2 Fault reset types 25
9.3 Alarm list 26
10. Programming and monitoring 29

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10.1Introduction 29
10.2Serial communication 29
10.2.1 Modbus (RTU) configuration 29
10.2.2 Data values, scaling and data types 30
10.2.3 Reading and writing 32 bit values via Modbus 30
10.2.4 Modbus function codes 30
10.2.5 Modbus exception codes 31
10.3Parameters 31
10.3.1 Control –application 31
10.3.2 Status –alarm 32
10.3.3 Status –compressor 33
10.3.4 Status –motor 34
10.3.5 Status –device 35
10.3.6 Status –IO 35
10.3.7 Configuration –application 35
10.3.8 Configuration –compressor 36
10.3.9 Configuration –COM1 37
10.3.10 Logs –application 37
10.3.11 Info –compressortype 37
11. Trouble shooting 39
11.1Communications trouble shooting 39
11.2Status LEDs 40
11.3LED flashing patterns of the three operation status LEDs 40
12. Notes 43

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1. Read this first!
The contents of this manual are subject to change without further notice.
Lodam electronics holds the copyright to this reference guide. The user shall follow any instructions given
in this reference guide entirely and not only partly. Any non-following of this reference guide result in
exclusion of all warranties, guarantees, and liabilities.
Copyright© 2015 by Lodam electronics a/s. All Rights Reserved.
Disposing of the parts of the controller:
INFORMATION FOR USERS ON THE CORRECT HANDLING OF WASTE ELECTRICAL AND
ELECTRONIC EQUIPMENT (WEEE)
In reference to European Union directive 2012/19/EU and the related national legislation, please note that:
1. WEEE cannot be disposed of as municipal waste and such waste must be collected and disposed of
separately
2. The public or private waste collection systems defined by local legislation must be used. In addition,
the equipment can be returned to the distributor at the end of its working life when buying new
equipment
3. The equipment may contain hazardous substances: the improper use or incorrect disposal of such
may have negative effects on human health and on the environment
4. The symbol (crossed-out wheeled bin) shown on the product or on the packaging and on the
instruction sheet indicates that the equipment must be disposed of separately
5. In the event of illegal disposal of electrical and electronic waste, the penalties are specified by local
waste disposal legislation.
Reading instructions
The following symbols are used to draw the reader’s attention to different warning levels.
Important information
Danger!! General danger
Danger!! High voltage. Danger of electrical current or voltage

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1.1 Reference guide
Before installation, the user should be thoroughly familiarized with this reference guide,
especially with purposes, installation and operation.
Special care should be taken when installing and connecting external equipment (PTC
sensor, high voltage etc.) and handling the modules correctly according to protection
against ESD (Electro Static Discharge).
Installation of the CM-RC-01 must be performed by authorized personnel only. All
warranties are excluded in case installation is performed by unauthorized personnel or
in case the CM-RC-01 has not been correctly installed.
1.2 Safety
The CM-RC-01 is a protection device and not a safety component according to the
Machinery Directive and cannot be used in “medical” or “life support” equipment
Before commissioning, the service technician shall ensure that personal safety
requirements are met in conformity with the Machinery Directive and local legislation
based on safety estimations.
Electrical plant failures are to be immediately solved, even though no immediate
danger exists; the CM-RC-01 and motor must be without power.
Before soldering or welding on the compressor, all connections on the CM-RC-01 must
be secured against overvoltage!

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2. General
The compressor control module CM-RC-01 is used for protection, control and diagnosis of
primarily reciprocating compressors. It is mounted in its own housing and connected to all the
sensors and components mounted on the compressor.
Its relays are used for compressor start and for the safety chain for the compressor and will open
in case of a critical failure.
The module has indicator lights visible from outside of the housing. It can be used as a stand-
alone control and protection module, or connected to a System Controller via the communication
bus to extend possibilities.
Some basic module setup related to motor-, compressor- and refrigerant type must be done to
enable all available protection functions. This is done with the BITZER BEST Software.
The CM-RC-01 module monitors and controls compressor operation according to the following
functions:
Motor overload
Oil level or oil pressure differential
Discharge gas temperature
Saturated suction and discharge gas temperature based on pressure readings
Absolute limits for low suction pressure and high discharge pressure
Motor start with built-in timers
Start-unloading control
Capacity control (CRII)
Liquid injection cooling (CIC)
Additional fan cooling control
Compressor application limits monitoring based on saturated gas temperatures
Modbus communication
2.1 Support information
BITZER Kühlmachinenbau GmbH
Eschenbrünnlestraẞe 15 // 71065 Sindelfingen // Germany
Tel [phone] // Fax [phone]
[e-mail] // www.bitzer.de

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3. Definitions
BEST
BEST Software
CR
Capacity Regulation
DOL
Direct On Line (motor start)
ESD
Electro Static Discharge
HP
High Pressure
HW
Hardware/electronics.
I/O
Input / Output (electrical signals in and out of a unit)
LP
Low Pressure
Modbus
Application-layer messaging protocol - http://www.modbus.org/specs.php
NC
Normally Closed (relay)
NO
Normally Open (relay)
NTC
Negative Temperature Coefficient (sensor element)
PTC
Positive Temperature Coefficient (sensor element)
PW
Part winding (motor start)
FI
Frequency inverter
Y/∆
Star/delta (motor start)

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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.

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4.1.2 Oil heater
The oil heater ensures lubricity of the oil even after long standstill periods. It prevents increased
refrigerant dilution in the oil and therefore a reduction of viscosity.
The oil heater is switched on during standstill and switched off during compressor operation.
4.1.3 Cylinder head and motor cooling
Under some conditions, additional cooling is needed as the sample diagram from the BITZER
Software below shows
Legend
Additional cooling & suction gas superheat ≤20K
Additional cooling & max. suction gas temperature <0°C
Additional cooling
M1: motor 1
M2: motor 2
Operating point
The CM-RC-01 has two independent functions to apply cooling to the compressor, an additional
fan and liquid injection cooling, CIC. The two functions are controlled by the CM-RC-01 module.
The additional fan cooling and/or CIC are automatically applied, if the compressor is in an
operating point where extra cooling is needed and the compressor is equipped with these
components.
BEST Software can configure the CM-RC-01 for the mounted options.
4.1.3.1 Additional fan
The CM-RC-01 will start and stop the additional fan according to the application limits for the
compressor and the selected refrigerant. The control algorithm in the CM-RC-01 starts the
additional fan if the discharge gas temperature gets too high.
It is for additional cooling of the compressor motor and cylinder heads.
When started, the fan will keep running for a certain minimum period, and until the temperature
drops to an acceptable level.
A warning message is displayed if the fan needs to be started too often.

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4.1.3.2 Liquid injection cooling (CIC)
CIC is a cooling system to reduce the discharge gas temperature. The control algorithm for the
liquid injection cooling in the CM-RC-01 starts the CIC if the discharge gas temperature gets too
high.
4.1.4 Capacity control
The CM-RC-01 can control the needed capacity of the compressor by controlling the CRII valves.
The 0 –10 V Cap. In input or the Modbus parameter Serial setpoint (see section 0 ) can be used
to specify the needed capacity of the compressor. The compressor must be mounted with a CRII
capacity regulation system.
The CM-RC-01 will operate the CRII valve(s) to achieve the requested capacity with as little
pressure fluctuations as possible.
The capacity range is 10 % - 100 %.
When liquid injection cooling (CIC) needs to run due to high discharge temperature, the capacity
system will be forced to run with a certain minimum capacity, in order to avoid flooding of the
compressor.
4.2 Monitoring and diagnosis
4.2.1 Motor temperature
One of the functions of the CM-RC-01 is to protect the compressor motor against overload.
By monitoring the resistance in a PTC sensor mounted in the motor windings, the CM-RC-01 will
lockout and stop the motor if the resistance increases above the limit as shown below.
When the lockout has been activated, the two start relays K1 and K2 are released immediately to
stop the compressor.
There is a restart blocking function to prevent the motor from being started too soon after having
been overheated.

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If the CM-RC-01 is locked, 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.
When power is turned on to the CM-RC-01 module, the PTC resistance is measured:
If PTC resistance is below the reset limit 2,7 kΩ:
No alarm: The relays are energized immediately (if no other faults are present)
If PTC resistance is between 2,7 kΩ and 4,5 kΩ:
Alarm: The relays are first energized when below 2,7 kΩ
(compressor motor has cooled down)
If PTC resistance is above 4,5 kΩ:
Alarm lock: The relays are not energized and the module is locked
4.2.2 Discharge temperature
A temperature sensor is mounted on the discharge side of the compressor; the CM-RC-01 will
open the relays and break the safety chain if the discharge temperature threshold is exceeded.
The default thresholds for the selected reciprocating compressor are defined in the BEST
software.
4.2.3 Oil supply
Depending on the compressor type, the oil supply monitor is configured for either oil level (OLC-
D1) or oil pressure difference (DP-1) monitoring. Actual status is always accessible via Modbus.
If an oil level fault is detected, the status is immediately updated via Modbus. However, the first
90 seconds after compressor start, the fault signal is not activated. If the oil level is still too low,
the CM-RC-01 releases the fault relay and locks out immediately.
The OLC-D1 module (24 V version) must be used for the oil level detection.
A warning signal is set immediately if the compressor is running and the OLC input is open.
If an oil pressure difference fault is detected, the status is immediately updated via Modbus. The
first 90 seconds after compressor start, the fault signal is not activated. If the oil pressure
difference is still too low, the CM-RC-01 releases the fault relay and locks out immediately.
Both oil fault alarms must be externally reset by either powering off the device for minimum 5
seconds or sending a reset command on the serial bus.
4.2.4 High pressure handling
A high-pressure switch can be connected to the CN2 of the CM-RC-01. An alarm is set on
CN2:Relay NC and on Modbus if the high-pressure switch opens.
4.2.5 Pressure limits (option)
In the BEST software a low pressure and a high pressure limits can be configured. If one of the
limits are reached, the compressor is stopped and an alarm is issued.

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4.2.6 Application limits (option)
Optional pressure transducers are needed.
The application limits function monitors if the operating conditions of the compressor is within the
safe operation area limits –as shown in the BITZER Software when doing compressor
calculations.
The BITZER Software can be downloaded from BITZER’s homepage, www.BITZER.de.
The operating point is determined by the saturated suction and discharge gas temperatures, which
are calculated from the suction and discharge gas pressure based on the selected refrigerant.
The figure below shows the multi-level monitoring of the application limits and behaviour when a
limit is reached.
Active warning, critical and faults are set inactive when the operating point again is within the
reset-limit.
HP cut-out and LP cut-out are configured
in the BEST Software.
Evaporating temperature to(SST) [°C]
Condensing temperature tc(SDT) [°C]
HP cut-out
LP cut-out
Application limit
Warning reset
Warning limit
Critical limit (shut off after 30s)
Fault limit (Immediately shut-off)
High- and Low pressure cut-out
}Active 120 s after
compressor start
Fault limit, direct shut-off:
The compressor will stop
immediately if this limit is reached!
Envelope status = 6 Fault
Critical limit, shut-off after 30 s:
30s delay time to bring compressor
back inside application limit else the
compressor is stopped with a Fault
alarm
Critical (30s period starts)
Envelope status = 5 Critical
Warning limit:
Warning to system controller
No further actions
Envelope status = 4 Warning
Warning reset
Automatic clear of warning

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There are nine zones in the application limit as shown on the figure below.
Zone zero (the green-shaded area) is the normal, safe operation area within the application limits.
A warning and a fault will be given if the warning level
or fault level is reached.
After a stop due to fault limit, the fault can be reset when the compressor is stopped. If timed
resets are enabled, the CM-RC-01 will perform a timed reset otherwise an external reset is
required. The CM-RC-01 will start the compressor again if the start command is active or when it
is applied again.
Please observe:
There is no Application limits monitoring the first period after start of the
compressor. The period varies for the compressor type, can be up to 120 s.
4.2.7 Short-cycling warning
To protect the motor windings, the module will give a warning if the compressor is started too
many times within 1 hour, but the compressor will not be locked.
4.3 Datalog
The built-in data logger stores operation data, sensor data, alarms and events for further analysis
using the BEST Software.
The data are stored in the data logger flash memory at regular intervals together with counters
and statistics data collected and summarized over time. The lifetime of the different data varies.
The datalog contains the following type of entries
Alarms
Events
Datalog information
Periodic data
Statistics and counters
6.SH2.SL
1.SLDL
3.SLDH 4.DH
5.SHDH
7.SHDL
8.DL
Evaporating temperature t0(SST) [°C]
Condensing temperature tc(SDT)[°C]
0: Ok
Zone number, description and alarm number:
Zone 1: SST Low, SDT Low 3001
Zone 2: SST Low 3002
Zone 3: SST Low, SDT High 3003
Zone 4: SDT High 3004
Zone 5: SST High & SDT High 3005
Zone 6: SST High 3006
Zone 7: SST High & SDT Low 3007
Zone 8: SDT Low 3008
Zone 0: Normal operation within application
limit and no alarms
t0(SST) = Evaporating temperature
tc(SDT) = Condensing temperature

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4.3.1 Alarms
Information logged:
Timestamp
Alarm code and text
Severity, can be Fault, Critical or Warning
Set or Clear
Critical and warnings have Set and Clear entries. E.g.
23-11-2015 03:58
4301: Motor Temperature High - Warning - Set
…
23-11-2015 04:02
4301: Motor Temperature High - Warning - Clear
For faults only Set entries are found. E.g.:
07-11-2015 11:01
3431: High Pressure Switch - Fault - Set
When all faults are successfully reset and the CM-RC-01 is no longer in fault state, there is an
entry like this:
02-12-2015 10:45
0: No Fault - Fault - Clear
Lifetime of alarm entries: 365 days.
4.3.2 Events
Possible events:
Power Up
Power Down
Extern alarm reset
Compressor Start
Compressor Stop
Service tool connect
Lifetime of events: 30 days
4.3.3 Datalog information
If bad sections are found in the datalog storage during download, an event is entered, telling that
this has happened. If possible, information is added about the number of log entries that was lost.
4.3.4 Periodic data
Data are stored on a regularly basis.
10 seconds interval when the compressor is running, 60 seconds when stopped.
3 seconds interval for fault traces.
Lifetime of events: 1 –3 weeks
4.3.5 Statistics and counters
Every midnight at 0:00 and at every Power Down a number of entries with counters or statistics
are logged.
Every one of these entries has a timestamp and some specific data as described below.

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4.3.6 Accumulated operation counters
All accumulated since first power up
No of PowerUps
No of Motor Starts
Operating Hours
Motor Operating Hours
Lifetime: 365 days
4.3.7 Capacity load
Device Operating Time –number of minutes, that is basis for the next values
Cap.Load 0 –percentage of the time, where the compressor was at standstill
Cap.Load 11-20 –percentage of the time, where the compressor had a load in the range
11-20 %
…
Cap.Load 91-100 –percentage of the time, where the compressor had a load in the range
91-100 %
Lifetime: 365 days
4.3.8 Daily counters
Device Power Ups
Compressor Starts
Number of Faults
Number of Criticals
Number of Warnings
Device Operating Time
Compressor Runtime
Fault Runtime
Critical Runtime
Warning Runtime
Capacity Usage Rate
Lifetime: 365 days
4.3.9 Runtime statistic
Number of runs 0-4 min
Number of runs 5-9 min
Number of runs 10-19 min
Number of runs 20-29 min
Number of runs 30-59 min
Number of runs 60-119 min
Number of runs 120-299 min
Number of runs >300 min
Lifetime: 365 days
4.3.10 Compressor start statistic
starts/h
2-4 starts/h
5-9 starts/h

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10-14 starts/h
15-19 starts/h
>20 starts/h
Lifetime: 365 days
4.4 BEST software
The BEST Software is used for live monitoring of operation conditions, download of datalogs and
configuration of the CM-RC-01.
The BEST Software can be downloaded from the BITZER homepage, www.bitzer.de.
4.5 Communication
Detailed status information and communication with the system controller is done via the Modbus
(RTU) interface.
Please see the detailed description in section 10 Programming and monitoring.
A Bluetooth module will be added soon.

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5. Control of the CM-RC-01
Control commands and setpoint can be given to the CM-RC-01 via different interfaces
Digital inputs: Start/stop
Analogue input: Setpoint
Serial control: Commands and setpoint
The commands from the different interfaces are merged and the resulting “Control Word” can be
read via the serial Interface.
The capacity is limited between 10 % and 100 % even if the sum of the setpoints may be below
100 % or above 100 %.
The serial protocol is Modbus (RTU). Modbus can be connected for example for monitoring only
but still using the digital and analogue inputs for control of the CM-RC-01. Most common is to
monitor and control the CM-RC-01 via the Modbus interface.
The serial control is inactive by default. Please see section 5.2 Enable serial control.
5.1 Commands and setpoint
The basic operation of the CM-RC-01 is controlled by
Commands: Start and stop
Setpoint –analogue or serial control
Setting of serial control parameters
o"Serial Control Source"; default is none: 0 –10V input
See parameter in section 10.3.7 Configuration –application
oSetting of the refrigerant (if not done via the BEST Software)
Commands and setpoint can be given via the digital and analogue inputs or by combining the
digital and analogue inputs with values from the serial interface. See later in this section.
5.1.1 Command Start
The Start command becomes active when a start signal is given via digital input or serial control.
If the compressor is started too many times per hour, the CM-RC-01 will give a waning but the
compressor will be allowed to start
The speed of the motor will normally match the setpoint. Details are described below.
When the motor is running and the start condition is removed (Start is set to inactive), the
compressor is stopped.
5.1.2 Setpoint –and speed changes
The setpoint is a value in the range -100 % to +100 %. There is no ramping of a capacity change
request. The setpoint from the analogue input and the serial control are added. E.g. the analogue
signal could be an offset and the serial control could be the fine tuning.
Analogue control: Apply a 0 –10V speed signal (0 –100%) to the CN13 Cap. Input.
Serial control: Set the capacity request in parameter Serial Setpoint (-100 % –+100%)
Please see section 10.3.1 Control –application for the parameter to use for the setpoint.

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5.2 Enable serial control
The serial control is inactive by default.
To enable the serial control set the parameter to 1 (COM1 Modbus).
To disable serial control:
Set parameter “Serial Control Source” to 0 (= None).
5.3 Required signals to start the compressor
Min. signals required to start the compressor via the CM-RC-01
5.3.1 Digital and analogue signals
Serial Control Source = 0 (None)
Start command
CN2:Relay C
Setpoint
CN13:Cap. Input
Compressor
State
–
–
Stopped
Off
–
Stopped
On
0 –100%
Running
Note: Please observe max number of starts per hour
5.3.2 Serial control (Modbus)
Serial Control Source = 1 (Modbus)
Start command
Control Word
Setpoint
Serial Setpoint
Compressor
state
–
–
Stopped
Off
–
Stopped
On
±100 %
Running
Note: Please observe max number of starts per hour
Control commands can be given to the CM-RC-01 via the Serial Control Word. The bit definitions
are shown in the table below.
The protocol used is Modbus (RTU). Modbus register definitions are listed in section 10.3
Parameters.
5.4 Control Word bit definitions
Bit
Function
Description
0-2
Reserved
Must be set to 1
3
Operation enable
Enable operation (0=off, 1 = enabled)
4
Reserved
Must be set to 1
5
Reserved
Must be set to 1
6
Start
Start command is active when bit = 1
7
Reset
Reset alarm command is active when bit is set from 0 to 1.
Positive edge triggered.
8-9
Reserved
10
Data valid
Instruct controller to accept control word. Otherwise all other
bits are ignored.
The resulting control word will always have this set.
Please see section 10.3.1 Control –application
11-15
Reserved
The data valid bit must be set to update the serial control word and the serial setpoint.

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The Control Word is the active control word.
Use the Serial Control Word for configuration of the CM-RC-01.
5.4.1 Data valid bit
When the data valid bit is set to “1” setpoint and commands are accepted from the serial control
interface.
When the data valid bit is set to “0” all other bits in the control word and the setpoint are ignored.
This means that if the start command was active just before the data valid bit is set to “0” the
command remains active until the data valid bit is set to “1” and the start bit is set to “0”.
Please note that the Serial Control Source must be 1 (Modbus).
5.5 Examples of Serial Control Word setups:
Command
Hexadecimal
value
Decimal
value
Binary
Reserved
Data valid
Reserved
Reset
Start
Reserved
Operation enable
Reserved
No command
43F
1087
0000 0
1
00
0
0
11
1
111
Start
47F
1151
0000 0
1
00
0
1
11
1
111
Reset
4BF
1215
0000 0
1
00
1
0
11
1
111
Stop
437
1079
0000 0
1
00
0
0
11
0
111
‘No command’ is the neutral value allowing digital control.
The neutral value of the control word is 43F hex (= 1087 dec = 10000111111 binary)
To start the compressor, the control word must be 47F hex (= 1151 dec = 10001111111 binary)
To disable this interface: Please see section 10.3.7 Configuration –application.
In the status word the actual status of the CM-RC-01 can be seen.
5.6 Status Word bit definitions
CM-RC-01 Status Word
Bit
Function
Description
0
Control
ready
The control is ready to switch on
0: Control not operational
1: The control is ready for operation
1
Operation
ready
The CM-RC-01 is ready to operate
0: Output is not ready
1: Output is ready
2
Operation
enabled
0: Output is off. Compressor is stopped
1: Compressor is on
3
Fault
0: No fault present
1: A fault is present. The compressor is stopped
4
Reserved
5
Reserved
6
Start disabled
0: Start is enabled.

v. 3.0
Reference guide
Compressor Control Module CM-RC-01
3.0
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5.7 Setting the serial setpoint
The serial setpoint is set via the Modbus holding register 111:
Modbus
type & addr
Name
Possible
values
Default
Description
HR 111
Serial Setpoint
(Control.SerSetpoint)
-100.00 % -
100.00 %
scale 100
sint16
0 %
Capacity setpoint written by serial
communication
5.8 Serial Control Timeout Function
If the communication is interrupted, the CM-RC-01 can be configured for different reactions to this
interrupt
None –continue operation
Stop –stop operation
Fault –Stop and signal fault alarm
Default function is to let the CM-RC-01 continue without any changes (None).
The timeout for activation and the different reactions of the Serial Control Timeout Function can be
adjusted. Every update of the Serial control word resets the timeout function.
Default timeout is 60 seconds.
Please see section 10.3.7 Configuration –application for further information.
1: Start is disabled
7
Warning
0: No warning present
1: A warning is present. The CM-RC-01 continues operation, but
attention may be required
8
On reference
0: The compressor is ramping or not running
1: The compressor is operating at setpoint
9
Reserved
10
Reserved
11
Running
0: Compressor is not running
1: The compressor is running
12
Start active
0: Start command is not given OR start is prohibited
1: Start command is given (e.g. start signal is given, setpoint > 0 %) and
Operation is enabled
13
Critical
0: No critical present
1: A critical is present. The CM-RC-01 is close at its limits and may soon
stop the compressor
14-
15
Reserved