Modbus Protocol - Johnson Controls YEWS Series Installation, Operation And Maintanance Instructions

5.7 Modbus protocol

(1) Modbus protocol instructions
Baud rate
Word length
Parity
Stop bits
Data mode
verify
(2) ModBus node list
Address Functions
3,6
201
202 3,6
203 3,6
204 3,6
205 3,6
206 3
3
207
208 3
209 3
210 3,6
System1
3
101
102 3
121 3
103 3
122 3
3
104
105 3
106 3
107 3
108 3
3
109
115 3
116 3
117 3
112 3
3
111
44
9600
8
None
1
RTU
CRC
Description
Start/stop
Mode select
AC: LEL setting
ITS: LEL setting
Heat pump: LHL setting
Alarm
Runtime limit
Oil Pre-heating
CONTROL MODEL
Heat pump: LHL setting
Digital output
Digital input
Zleaving condenser Liquid
Enter condenser Liquid
Leaving evaporator Liquid
Enter evaporator Liquid
Discharge Temperature
Evaporator pressure
Discharge pressure
Oil pressure
Motor current
DI fault
AI fault
RUN fault
Water pump operation time
Compressor operation time
YEWS-E Water Cooling Screw Chiller/Heat Pump
Word length note
Command 1:start, 2:stop
word
Status 0:stop,1:start
word 0:AC 1:ITS 2:HP 3:REMOTE
Range： 4.0 – 15.0℃
word
Range：-8.0 – +5.0℃
word
word YEWS-D1 HP Range: 30.0 - 60.0℃
YEWS-E HP2 Range: 30.0 - 60.0℃
word
1: yes 0: no
word
1: yes 0: no
word 1: yes 0: no
word 0 LOCAL 1 REMOTE 2 MODBUS
word YEWS-E HP Range: 30.0 - 50.0℃
word
See table 4/table 5
word
word Signed binary，the value is multiplied per 10
word
Signed binary，the value is multiplied per 10
word Signed binary，the value is multiplied per 10
word
Signed binary，the value is multiplied per 10
word unsigned binary，the value is multiplied per 10
word unsigned binary
word
unsigned binary
word unsigned binary
word
unsigned binary，the value is multiplied per 10
word
word See table 1/ table 2/ table 3
word
word accumulative total
word
accumulative total