14
Modbus RTU Communications
The standard controller has Modbus RTU communications enabled with the following default setup: Baud rate =
57,600, data length = 8 bits, parity = odd, and stop bit = 1.
Table 9 – Modbus Parameters
Register
Format
Parameter
Data
Access Level
Comment
00000
BOOL
UNIT START/STOP
BIT
R/W
UNIT ON/OFF BY MODBUS
10000
BOOL
SYSTEM RUNNING
BIT
R
10001
BOOL
REMOTE MODE
BIT
R
REMOTE MODE ENABLE/DISABLE
10002
BOOL
COMPRESSOR ENABLE
BIT
R
10003
BOOL
PUMP ENABLE
BIT
R
10004
BOOL
FAN ENABLE
BIT
R
10005
BOOL
CONDENSER ENABLE
BIT
R
10006
BOOL
AUTO FLUID MAKEUP VALVE
BIT
R
10007
BOOL
LIQUID LINE SOLENOID VALVE
BIT
R
10008
BOOL
TANK LOW LEVEL ALARM
BIT
R
10009
BOOL
PHASE LOSS ALARM
BIT
R
10010
BOOL
PUMP OVERLOAD ALARM
BIT
R
10011
BOOL
FAN OVERLOAD ALARM
BIT
R
10012
BOOL
LOW FLOW ALARM
BIT
R
10013
BOOL
HIGH SUPPLY FLUID TEMPERATURE ALARM
BIT
R
10014
BOOL
HIGH RETURN FLUID TEMPERATURE WARNING
BIT
R
10015
BOOL
LOW SUPPLY FLUID TEMPERATURE ALARM
BIT
R
10016
BOOL
LOW RETURN FLUID TEMPERATURE WARNING
BIT
R
10017
BOOL
SUPPLY FLUID TEMPERATURE SENSOR ALARM
BIT
R
10018
BOOL
RETURN FLUID TEMPERATURE SENSOR ALARM
BIT
R
10019
BOOL
FREEZESTAT ALARM
BIT
R
10020
BOOL
HIGH REFRIGERANT PRESSURE ALARM
BIT
R
10021
BOOL
LOW REFRIGERANT PRESSURE ALARM
BIT
R
10022
BOOL
LOW LOW REFRIGERANT PRESSURE ALARM
BIT
R
30000
UINT
COOLING TYPE
1
R
0 = AIR COOLED
1 = REMOTE COOLED
2 = WATER COOLED
30001
REAL
PROCESS SETPOINT °F
2
R
30003
REAL
SUPPLY FLUID TEMPERATURE °F
2
R
30005
REAL
RETURN FLUID TEMPERATURE °F
2
R
30007
REAL
HOT GAS BYPASS VALVE %
2
R
30009
REAL
SOFTWARE VERSION
2
R
30011
UDINT
COMPRESSOR RUN HOURS
2
R
30013
UDINT
PUMP RUN HOURS
2
R
30015
UDINT
FAN RUN HOURS
2
R
40000
REAL
TARGET SETPOINT °F
2
R/W
TARGET TEMPERATURE °F