User Guide

SKVF Evaporative Cooler
Modbus Communication Module User Guide
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Modbus Registers
Table Glossary
Name
Description
Name
Description
W
Writable Register
ASCII
For registers containing ASCII (8-bit) characters
RO
Read Only Register
MSB
Most Significant Byte
Unsigned
For range of values from 0 to 65,535, unless otherwise specified
LSB
Least Significant Byte
Signed
For range of values from -32,768 to 32,767, unless otherwise
specified
MSW
Most Significant Word
Bit String
For registers with multiple values using bit mask (example,
flags)
LSW
Least Significant Word
Modbus Registers Table
Protocol
Base
Holding
Register
Description
Data Type
Units, Limits, State Texts
Writa
ble
Default Value
0
400001
Modbus Address and Product Type
Unsigned
MSB = Product type, not writable
LSB = Modbus Address (1 to 247), writable
W
1
400002
Device Baud Rate
Unsigned
Scale 100
0, 9600, 19200, 38400, and 57600, 0 = Auto Baud Rate
Detection Value/100 (e.g. 38400 baud = 384)
W
19200
2
400003
Modbus Slave Communication Port
Configuration
Unsigned
0 = No parity, 2 Stop bits
1 = Even parity, 1 Stop bit
2 = Odd parity, 1 Stop bit
W
No parity,
2 Stops bits
3
400004
Product Name (characters 8 & 7)
ASCII
MSB = char 6, LSB = char 7
W
4
400005
Product Name (characters 6 & 5)
ASCII
MSB = char 4, LSB = char 5
W
5
400006
Product Name (characters 4 & 3)
ASCII
MSB = char 2, LSB = char 3
W
6
400007
Product Name (characters 2 & 1)
ASCII
MSB = char 0, LSB = char 1
W