Condair Modbus RTU - Page 40

37 | Modbus Installation
Modbus Parameters
The MHTC uses the following parameters for communication:
Signaling Type
EIA-485
Transmission Mode
RTU
Baud Rate
9600 (cannot be changed)
Data Bits
8
Stop Bits
1
Parity
None
Address / Unit Number
1*
*Default, may vary for multi-unit orders.
It is important to note that the signaling type, transmission mode, baud rate, data bits and stop
bits cannot be modified. Parity and unit address can be modified as required.
The following points may be mapped for control:
Table 7: MHTC Humidifier Modbus Parameters
Variable
Name
Description
Addr
Type
Format
Range
Unit
R/W
Details
CapLimit
Manual
Capacity Limit
40008
Holding
Register
Integer
30 -
100
%
Write
Limits unit output.
RHDem1
Reads/writes a
control signal to
the humidifier
40053
Holding
Register
Integer
0 - 100
%
Write
Writes a control signal to
the humidifier. This input
only works if humidifier is
set to network control
NetSensor set to 1) in
the control settings. If
the system is set to
network control no signal
is detected, the unit will
display the modbus
timeout error.
Set1
Reads/Writes
the desired
space setpoint
40005
Holding
Register
Integer
10 - 90
%
Write
Used when Hum_Control
= 2 or 3 only
Disable
Remotely
disables
humidifier
40052
Holding
Register
Integer
0 or 1
-
Write
0 = Allow normal
humidifier operation
1 = Remotely disables
the humidifier
Hum_Control
Selects the
control type
that the
humidifier
operates on
40003
Holding
Register
Integer
0 - 3
-
Write
0 = Demand Signal
1 = On/Off Signal
2 = RH Sensor Value
(Use Proportional control
method)
3 = RH Sensor Value
(Use Proportional-Integral
control method)
NetSensor
Switches
between hard
wired or
network control
signal
40002
Holding
Register
Integer
0 or 1
-
Write
0 = Wired Analog
Sensor/Demand
1 = Modbus/Remote
Sensor/Demand
Stage1Dem
Indicates
output from
humidifier
stage 1
30025
Input
Register
Integer
0 or 1
-
Read
0 = Inactive
1 = Active