Instructions

Intesis
®
INMBSMIT001I000
User’s Manual r2.4 EN
© HMS Industrial Networks S.L.U - All rights reserved
This information is subject to change without notice
URL https://www.intesis.com
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3. Modbus Interface Specification
3.1 Modbus physical layer
INMBSMIT001I000 implements a Modbus RTU (Slave) interface, to be connected to an EIA-485
line. It performs 8N2 communication (8 data bits, no parity and 2 stop bit) with several
available baud rates (2400 bps, 4800 bps, 9600 bps -default-, 19200 bps, 38400 bps, 57600
bps, 76800 bps and 115200 bps). It also supports 8N1 communication (8 data bits, no parity
and 1 stop bit).
3.2 Modbus Registers
All registers are type “16-bit unsigned Holding Register” and they use the standard Modbus big
endian notation.
3.2.1 Control and status registers
Register Address
(protocol address)
Register Address
(PLC address)
R/W
Description
0
1
R/W
AC unit On/Off
▪ 0:Off
▪ 1:On
1
2
R/W
AC unit Mode
1
▪ 0:Auto
▪ 1:Heat
▪ 2:Dry
▪ 3:Fan
▪ 4:Cool
2
3
R/W
AC unit Fan Speed
1
▪ 0:Auto
▪ 1:Low
▪ 2:Mid-1
▪ 3:Mid-2
▪ 4:High
3
4
R/W
AC unit Vane Position
1
▪ 0:Auto
▪ 1:Horizontal
▪ 2:Position-2
▪ 3:Position-3
▪ 4:Position-4
▪ 5: Vertical
▪ 10: Swing
4
5
R/W
AC unit Temperature Setpoint
1,2,3
▪ -32678 (Initialization value)
▪ 16..32ºC (ºC/x10ºC)
▪ 61..90ºF
5
6
R
AC unit Temperature reference
1,2,3
▪ -32678 (Initialization value)
▪ 10..38ºC (ºC/x10ºC)
▪ 50..100ºF
1
Available values will depend on the AC unit mode. Check the AC unit model functions in its User’s Manual to know the possible values
for this register.
2
Magnitude for this register can be adjusted to Celsius x 1ºC, Celsius x 10ºC (Default) or Fahrenheit. See section 3.2.3 for more
information
3
It is not possible turn to x10 the value shown in Fahrenheit.