Nortec Modbus - Manual (Page 29)

Control Signal Setting
By default the humidifier is configured operate on a hardwired control signal supplied through
the unit terminal strip. This can be changed to allow the humidifier to function entirely through
its Modbus interface.
To adjust this setting:
1 Press the Menu key to access the menu.
2 When prompted for a password, enter 0335 using the arrow keys. Confirm the password
with set.
3 Select the Control Settings menu and press the Set key. The following settings can be
adjusted:
Source
Analog: Use hardwired control signal
Digital: Write control signal through Modbus interface
REG Mode
Demand: Use a demand control signal
RHp: Use a sensor value and proportional
RHpi: Use a sensor value and proportional-integral control band
MOD Mode
Single CH: Use a signal channel control signal
Dual CH: Use a dual channel control signal
CNT Type Setting not relevant when writing control signal through Modbus.
Note: Refer to the SETC Humidifier Configuration section of the SE Series Installation and
Operation Manual for more information on the above settings.
1 Press Esc repeatedly to return to the home screen when complete.
This procedure is summarized below:
Menu > 0335 > Control Settings >
Source: Analog or Digital
Reg Mode: Demand, RHp, or RHpi
Mod Mode: Single CH or Dual CH
CNT Type: As required
Modbus Parameters
The SETC uses the following parameters for communication:
Signaling Type EIA-485
Transmission Mode RTU
Baud Rate 9600
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.
26 |Modbus Installation