Navien NHB Series, Installation & Operation Manual

Page: 97 / 135

97 Operating the Boiler
Setting Detailed Building Management System (BMS) information
The boiler’s firing rate and set point can be controlled by 0 – 10
V Building Management System (BMS) input, if BMS Status is set
to
Enabled . If BMS Status is set to Disabled , 0 – 10 V Building
Management System (BMS) input is ignored. To set the detailed
Building Management System (BMS) information, tap
Detailed
Settings on the BMS Status menu.
Item Description
1. Min (Firing rate)
Set the minimum firing rate for BMS
control.
Ɣ
Setting range: 0.1% –
[2. Max (Firing rate) - 20%]
Ɣ
Default: Boiler MIN HC
2. Max (Firing rate)
Set the maximum firing rate for BMS
control.
Ɣ
Setting range: [1. Min (Firing rate) +
20%] – 100%
Ɣ
Default: 100%
3. Min (Volts)
Set the minimum voltage for BMS
control.
Ɣ
Setting range: 0 V – [Volts Max - 1 V]
Ɣ
Default: 2 V
4. Max (Volts)
Set the maximum voltage for BMS
control.
Ɣ Setting range: [Volts Min + 1 V] – 10 V
Ɣ
Default: 10 V
5. BMS mode
Select the BMS mode (Firing rate or
Setpoint).
Ɣ
Default: Firing Rate
6. BMS Enable Volts
Set the BMS activation voltage. Boilers
operates when the input voltage
exceeds the set voltage.
Ɣ
Setting range: 0 V – 10 V
Ɣ
Default: 2 V
11.5.6 Setting General Building Management
System (BMS) Information
To set the general Building Management System (BMS)
information, tap the EMS button (
) > EMS Set on the screen.
Item Description
1. BMS Status
Enable or disable the Building
Management System (BMS) function.
2. BMS Status /
Detailed Settings
Set the Building Management System
(BMS) function.
Note
For more information about
detailed settings, refer to
“Setting Detailed Building
Management System (BMS)
information.”.
3. Modbus RTU
Enable or disable the Modbus RTU
function.
Ɣ
Default: Enabled
Ɣ
If Enabled is selected, you can use
Modbus communication.
4. Baud Rate Setting Set the Baud rate and parity type.
5. Address Setting
Set the Modbus address.
Ɣ
0: Broadcast messages
Ɣ
1 – 100: Available address numbers
for each unit
Ɣ
Default: 1
6. Time Out Setting
Set the timeout after transmission.
Ɣ
Setting range: 100 ms – 1000 ms
Ɣ
Default: 100 ms
Note
For more details on Modbus RTU, refer to the Modbus
RTU Installation & Operation Manual.