Neptronic SKS4 Modbus User manual
SKS4-Modbus Guide-191017
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
www.neptronic.com
Page | 1
Introduction
The SKS4 Modbus Communication Module User Guide provides information for using Neptronic®communication
feature. The controller uses Modbus communication protocol over serial line in the RTU mode and provides a Modbus
network interface between client devices and Neptronic SKS4 devices.
The SKS4 Modbus Guide assumes that you are familiar with Modbus terminology.
The following are the requirements for Modbus:
•Data Model. The SKS4 Steam to Steam Humidifier Modbus server data model uses only the Modbus
Registers table.
•Register Address:
oAs per protocol base (base 0); for PLC add 1 to protocol base.
oAs per holding register (base 400001).
Note: Ensure that the Modbus communication software used does not have a limit on the range of the
register addresses that can be viewed and supports 6-digit holding registers.
•Function Codes. The SKS4 Steam to Steam Humidifier Modbus server supports a limited function codes
subset comprising:
oRead Holding Registers (0x03)
oWrite Single Register (0x06)
oWrite Multiple Registers (0x10)
•Exception Responses. The SKS4 Steam to Steam Humidifier Modbus server supports the following exception
codes:
oIllegal data address
oIllegal data value
oSlave device busy
•Serial Line. The SKS4 Steam to Steam Humidifier Modbus over serial line uses RTU transmission mode over
a two-wire configuration RS485 (EIA/TIA-485 standard) physical layer.
oThe physical layer can use fixed baud rate selection or automatic baud rate detection (default) as
per the Modbus Auto Baud Rate device menu item or holding register index 1.
oThe supported baud rates are 9600, 19200, 38400, and 57600.
oThe physical layer also supports variable parity control and stop bit configuration as per the Modbus
Comport Config device menu item or holding register index 2.
oIn auto baud rate configuration, if the device detects only consecutive bad frames (2 or more) for
one second with any given baud rate, it will reinitialize itself to the next baud rate.
•Addressing. The SKS4 Steam to Steam Humidifier device only answers at the following address:
oThe device's unique address (1 to 246) that can be set through the device menu or through holding
register index 0.
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
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Page | 2
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
Writable
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
7
400008
Product Actual Firmware Version (in
Integer x100)
Unsigned
Scale 100
1 to 65535 (e.g. 100)
RO
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
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Protocol
Base
Holding
Register
Description
Data Type
Units, Limits, State Texts
Writable
Default
Value
8
400009
Product Actual EEPROM Version (in
Integer x100)
Unsigned
Scale 100
1 to 65535 (e.g. 100)
RO
2000
402001
Control Signal
Unsigned
Scale 1000
Units: Volt (V), Range: 0V to 15V
Value x 1000 (e.g. 1V = 1000)
RO
0V
2001
402002
Room RH Signal
Unsigned
Scale 1000
Units: Volt (V), Range: 0V to 15V
Value x 1000 (e.g. 1V = 1000)
RO
0V
2002
402003
Supply RH Signal
Unsigned
Scale 1000
Units: Volt (V), Range: 0V to 15V
Value x 1000 (e.g. 1V = 1000)
RO
0V
2003
402004
Water Level Signal
Unsigned
Scale 1
Units: Hz, Range: 0 to 30000Hz
Value x 1 (e.g. 10Hz = 10)
RO
0Hz
2004
402005
Water Level Low Signal
Unsigned
Scale 1000
Unit: Volt (V), Range: 0V to 10V
Value x 1000 (e.g. 1V = 1000)
RO
0V
2005
402006
Water Level High Signal
Unsigned
Scale 1000
Unit: Volt (V), Range: 0V to 10V
Value x 1000 (e.g. 1V = 1000)
RO
0V
2006
402007
Water Temperature Signal
Unsigned
Scale 1000
Unit: Volt (V), Range: 0V to 10V
Value x 1000 (e.g. 1V = 1000)
RO
0V
2007
402008
Foam Signal
Unsigned
Scale 1000
Unit: Volt (V), Range: 0V to 10V
Value x 1000 (e.g. 1V = 1000)
RO
0V
2008
402009
Cabinet Temperature Signal
Unsigned
Scale 1000
Unit: Volt (V), Range: 0V to 10V
Value x 1000 (e.g. 1V = 1000)
RO
0V
2009
402010
Board Temperature Signal
Unsigned
Scale 1000
Unit: Volt (V), Range: 0V to 10V
Value x 1000 (e.g. 1V = 1000)
RO
0V
2010
402011
Main Power Supply
Unsigned
Scale 10
Unit: Volt (V), Range: 0V to 40V
Value x 10 (e.g. 1V = 10)
RO
0V
2011
402012
Steam Valve Feedback Signal
Unsigned
Scale 1000
Units: Volt (V), Range: 0V to 10.5V
Value x 1000 (e.g. 1V = 1000)
RO
0V
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
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Page | 4
Protocol
Base
Holding
Register
Description
Data Type
Units, Limits, State Texts
Writable
Default
Value
4000
404001
Steam Output Feedback Signal
Unsigned
Scale 1000
Unit: Volt (V), Range: 0V to 10V
Value x 1000 (e.g. 1V = 1000)
RO
0V
6000
406001
Control Input
Unsigned
Scale 100
Unit: %, Range: 0% to 100%
Value x 100 (e.g. 10% = 1000)
RO
0%
6001
406002
Room RH
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
RO
0% RH
6002
406003
Supply High Limit RH
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
RO
0% RH
6003
406004
Water Temperature Signal Min
Unsigned
Scale 1000
Unit: Volt (V), Range: 0V to 10V
Value x 1000 (e.g. 1V = 1000)
RO
0V
6004
406005
Water Temperature Signal Max
Unsigned
Scale 1000
Unit: Volt (V), Range: 0V to 10V
Value x 1000 (e.g. 1V = 1000)
RO
0V
6005
406006
Water Temperature
Unsigned
Scale 100
Unit: ºC/ºF, Range: 0°C to 125°C or 32°F to 257°F
Value x 100 (e.g. 5°C = 500 or 40ºF = 4000)
RO
50°C or
122°F
6006
406007
Water Temperature Min
Unsigned
Scale 100
Unit: ºC/ºF, Range: 0°C to 250°C or 32°F to 482°F
Value x 100 (e.g. 5°C = 500 or 40ºF = 4000)
RO
0°C or 32°F
6007
406008
Water Temperature Max
Unsigned
Scale 100
Unit: ºC/ºF, Range: 0°C to 250°C or 32°F to 482°F
Value x 100 (e.g. 5°C = 500 or 40ºF = 4000)
RO
125°C or
257°F
6008
406009
Water Temperature Bias
Unsigned
Scale 100
Unit: ºC/ºF, Range: -10°C to 10°C or -18°F to 18°F
Value x 100 (e.g. 5°C = 500 or 14ºF = 1400)
RO
0°C or 32°F
6009
406010
Cabinet Temperature
Unsigned
Scale 100
Unit: ºC/ºF, Range: -20°C to 100°C or -4°F to 212°F
Value x 100 (e.g. 5°C = 500 or 10ºF = 1000)
RO
0°C or 32°F
6010
406011
Modbus TCP IP Keep Alive Time Out (0)
Unsigned
Scale 1
Unit: Minutes (min), Range: 1 to 1440 mins
Value x 1 (e.g. 5 mins = 5)
W
5 min
6011
406012
Modbus TCP IP Keep Alive Time Out (1)
Unit: Minutes (min), Range: 1 to 1440 mins
6012
406013
HRL Temperature
Signed
Scale 100
Unit: ºC/ºF, Range: -40°C to 260°C or -40°F to 500°F
Value x 100 (e.g. 5°C = 500 or 40ºF = 4000)
RO
0°C or 32°F
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
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Page | 5
Protocol
Base
Holding
Register
Description
Data Type
Units, Limits, State Texts
Writable
Default
Value
6013
406014
HRL Humidity
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 1% RH = 100)
RO
0% RH
6014
406015
Board Temperature
Unsigned
Scale 100
Unit: ºC/ºF, Range: 0°C to 100°C or 32°F to 212°F
Value x 100 (e.g. 5°C = 500 or 32ºF = 3200)
RO
0°C or 32°F
6015
406016
Power Output Feedback
Unsigned
Scale 100
Unit: %, Range: 0% to 100%
Value x 100 (e.g. 10% = 1000)
RO
0%
6016
406017
Water Level
Unsigned
Scale 10
Unit: %, Range: 0% to 120%
Value x 10 (e.g. 10% = 100)
RO
78%
6017
406018
Water Probe Low Pos Reading
Unsigned
Scale 1
Unit: Hz, Range: 0 to 30000 Hz
Value x 1 (e.g. 1 Hz = 1)
RO
30000Hz
6018
406019
Water Probe High Pos Reading
Unsigned
Scale 1
Unit: Hz, Range: 0 to 30000 Hz
Value x 1 (e.g. 1 Hz = 1)
RO
30000Hz
6019
406020
Water Probe Abs Low Pos Reading
Unsigned
Scale 1
Unit: Hz, Range: 0 to 30000 Hz
Value x 1 (e.g. 1 Hz = 1)
RO
30000Hz
6020
406021
Water Probe Abs High Pos Reading
Unsigned
Scale 1
Unit: Hz, Range: 0 to 30000 Hz
Value x 1 (e.g. 1 Hz = 1)
RO
30000Hz
6021
406022
Room RH Network Reading
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
RO
0% RH
6022
406023
Room RH Setpoint
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
W
40% RH
6023
406024
Room RH Unoccupied Setpoint
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
W
30% RH
6024
406025
Room RH Vacant Setpoint
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
W
20% RH
6025
406026
Room Demand
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
RO
0% RH
6026
406027
Supply High Limit Network Reading
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
W
0% RH
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
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Page | 6
Protocol
Base
Holding
Register
Description
Data Type
Units, Limits, State Texts
Writable
Default
Value
6027
406028
Supply High Limit Setpoint
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
W
80% RH
6028
406029
Supply High Limit Demand
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
RO
0% RH
6029
406030
Humidity Control Network Demand
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
W
0% RH
6030
406031
Humidity Control Network High Limit
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
W
100% RH
6031
406032
Humidity Demand
Unsigned
Scale 100
Unit: % RH, Range: 0% RH to 100% RH
Value x 100 (e.g. 10% RH = 1000)
RO
0% RH
6032
406033
Humidity Demand Low Dead Band (0)
Unsigned
Scale 100
Unit: %, Range: 0% to 100%
Value x 100 (e.g. 10% = 1000)
W
1%
6033
406034
Humidity Demand Low Dead Band (1)
Unit: %, Range: 0% to 100%
6034
406035
Network Timeout (0)
Unsigned
Scale 1
Unit: Seconds (sec), Range: 1 to 900 sec
Value x 1 (e.g. 10sec = 10)
W
900 sec
6035
406036
Network Timeout (1)
Unit: Seconds (sec), Range: 1 to 900 sec
6036
406037
System Power Output
Unsigned
Scale 100
Unit: %, Range: 0% to 100%
Value x 100 (e.g. 10% = 1000)
RO
0%
6037
406038
System Steam Capacity
Unsigned
Scale 10
Unit: kg/hr or lb/hr, Range: 0 to 300 kg/hr or
0 to 66 1lb/hr
Value x 10 (e.g. 10 kg/hr = 100 or 10 lb/hr = 100)
RO
0 kg/hr or
0 lb/hr
6038
406039
Water Level Replace Interval (0)
Unsigned
Scale 1
Unit: Days, Range: 0 day to 7 days
Value x 1 (e.g. 1 day = 1)
W
7day
6039
406040
Water Level Replace Interval (1)
Unit: Days, Range: 0 day to 7 days
Value x 1 (e.g. 1 day = 1)
6040
406041
AFKW Stp (0)
Signed
Scale 100
Unit: ºC/ºF, Range: -40ºC to 100ºC or -40ºF to 212ºF
Value x 100 (e.g. 10ºC = 1000 or 40ºF = 4000)
RO
30°C or 86°F
6041
406042
AFKW Stp (1)
Unit: ºC/ºF, Range: -40ºC to 100ºC or -40ºF to 212ºF
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
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Page | 7
Protocol
Base
Holding
Register
Description
Data Type
Units, Limits, State Texts
Writable
Default
Value
6042
406043
AF Keep Warm (0)
Signed
Scale 100
Unit: ºC/ºF, Range: -40ºC to 100ºC or -40ºF to 212ºF
Value x 100 (e.g. 10ºC = 1000 or 40ºF = 4000)
RO
10°C or 50°F
6043
406044
AF Keep Warm (1)
Unit: ºC/ºF, Range: -40ºC to 100ºC or -40ºF to 212ºF
6044
406045
AF Drain (0)
Signed
Scale 100
Unit: ºC/ºF, Range: -40ºC to 100ºC or -40ºF to 212ºF
Value x 100 (e.g. 10ºC = 1000 or 40ºF = 4000)
RO
1°C or 34°F
6045
406046
AF Drain (1)
Unit: ºC/ºF, Range: -40ºC to 100ºC or -40ºF to 212ºF
6046
406047
Boiler Demand
Unsigned
Scale 100
Unit: %, Range: 0% to 100%
Value x 100 (e.g. 10% = 1000)
W
0%
6047
406048
Boiler Capacity
Unsigned
Scale 10
Unit: kg/hr or lb/hr, Range: 0 to 3000kg/hr or
0 to 6613.8lb/hr
Value x 10 (e.g. 10 kg/hr = 100 or 10 lb/hr = 100)
RO
15 kg/hr or
33.06 lb/hr
6048
406049
Boiler Power Output
Unsigned
Scale 100
Unit: %, Range: 0% to 100%
Value x 100 (e.g. 10% = 1000)
RO
0%
6049
406050
Boiler Run Time (0)
Unsigned
Scale 100
Units: Hours (h), Range: 0 to 21474836.47 h
Value x 100 (e.g. 10h = 1000)
RO
0h
6050
406051
Boiler Run Time (1)
Units: Hours (h), Range: 0 to 21474836.47 h
6051
406052
Boiler Run Time (2)
Units: Hours (h), Range: 0 to 21474836.47 h
6052
406053
Boiler Run Time (3)
Units: Hours (h), Range: 0 to 21474836.47 h
6053
406054
Boiler On Time (0)
Unsigned
Scale 100
Units: Hours (h), Range: 0 to 21474836.47 h
Value x 100 (e.g. 10h = 1000)
RO
0h
6054
406055
Boiler On Time (1)
Units: Hours (h), Range: 0 to 21474836.47 h
6055
406056
Boiler On Time (2)
Units: Hours (h), Range: 0 to 21474836.47 h
6056
406057
Boiler On Time (3)
Units: Hours (h), Range: 0 to 21474836.47 h
6057
406058
Boiler Service Run Time (0)
Unsigned
Scale 100
Units: Hours (h), Range: 0 to 21474836.47 h
Value x 100 (e.g. 10h = 1000)
RO
0h
6058
406059
Boiler Service Run Time (1)
Units: Hours (h), Range: 0 to 21474836.47 h
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
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Page | 8
Protocol
Base
Holding
Register
Description
Data Type
Units, Limits, State Texts
Writable
Default
Value
6059
406060
Boiler Service Run Time (2)
Units: Hours (h), Range: 0 to 21474836.47 h
6060
406061
Boiler Service Run Time (3)
Units: Hours (h), Range: 0 to 21474836.47 h
6061
406062
Boiler Service On Time (0)
Unsigned
Scale 100
Units: Hours (h), Range: 0 to 21474836.47 h
Value x 100 (e.g. 10h = 1000)
RO
0h
6062
406063
Boiler Service On Time (1)
Units: Hours (h), Range: 0 to 21474836.47 h
6063
406064
Boiler Service On Time (2)
Units: Hours (h), Range: 0 to 21474836.47 h
6064
406065
Boiler Service On Time (3)
Units: Hours (h), Range: 0 to 21474836.47 h
6065
406066
Boiler Minimum Steam Output
Unsigned
Scale 1
Unit: %, Range: 1% to 25%
Value x 1 (e.g. 1% = 1)
W
5%
6066
406067
Boiler Drain Interval
Unsigned
Scale 1
Units: Hours (h), Range: 0 to 24 h
Value x 1 (e.g. 1 h = 1)
W
6h
6067
406068
Boiler Drain Volume
Unsigned
Scale 1
Unit: %, Range: 25% to 100%
Value x 1 (e.g. 30% = 300)
W
100%
6068
406069
Boiler Max Steam Output
Unsigned
Scale 1
Unit: %, Range: 0% to 100%
Value x 1 (e.g. 30% = 300)
W
100%
6069
406070
Boiler Idle Time Drain
Unsigned
Scale 1
Unit: Hours (h), Range: 0 to 72 h
Value x 1 (e.g. 1 h = 1)
W
24h
6070
406071
Boiler Idle Temperature Setpoint
Unsigned
Scale 1
Unit: ºC/ºF, Range: 0°C to 60°C or 32°F or 140°F
Value x 1 (e.g. 5°C = 500 or 32ºF = 3200)
W
0°C or 32°F
6071
406072
Boiler Blowdown Rate
Unsigned
Scale 1
Unit: %, Range: 0% to 100%
Value x 1 (e.g.1% = 1)
W
0%
6072
406073
Boiler Service Interval
Unsigned
Scale 1
Unit: Hours (h), Range: 1000 to 3000 h
Value x 1 (e.g. 1500 h = 1500)
W
1000h
6073
406074
Boiler Idle Tank Rinse Interval
Unsigned
Scale 1
Unit: Days, Range: 1 to 7 days
Value x 1 (e.g. 1 day = 1)
W
3 day
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
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Page | 9
Protocol
Base
Holding
Register
Description
Data Type
Units, Limits, State Texts
Writable
Default
Value
6074
406075
Actuator Deadband
Unsigned
Scale 1
Unit: %, Range: 0% to 25%
Value x 1 (e.g. 5% = 5)
W
5%
6075
406076
Steam Valve Feedback
Unsigned
Scale 100
Unit: %, Range: 0% to 100%
Value x 100 (e.g. 1% = 100)
RO
0%
10000
410001
Air Flow
Unsigned
Scale 1
0 = Closed
1 = Open
RO
Closed
10001
410002
Supply High Limit
Unsigned
Scale 1
0 = Closed
1 = Open
RO
Closed
10002
410003
Interlock
Unsigned
Scale 1
0 = Closed
1 = Open
RO
Closed
10003
410004
Binary External Demand
Unsigned
Scale 1
0 = 0%
1 = 100%
RO
0%
10004
410005
Water Leak Detection
Unsigned
Scale 1
0 = Ok
1 = Leak
RO
Ok
10005
410006
Thermal Cutout
Unsigned
Scale 1
0 = Closed
1 = Open
RO
Closed
10006
410007
RS485 Interface
Unsigned
Scale 1
0 = No
1 = Yes
RO
No
10007
410008
Ethernet Interface
Unsigned
Scale 1
0 = No
1 = Yes
RO
No
10008
410009
Contactors PCB Fuse
Unsigned
Scale 1
0 = Normal
1 = Blown Fuse
RO
Normal
10009
410010
Control PCB Fuse
Unsigned
Scale 1
0 = Normal
1 = Open Fuse
RO
Normal
11000
411001
Drain Valve
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
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Page | 10
Protocol
Base
Holding
Register
Description
Data Type
Units, Limits, State Texts
Writable
Default
Value
11001
411002
Alarm Warning Relay
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
11002
411003
Service Warning Relay
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
11003
411004
Water Level Valve
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
11004
411005
Tank Water Valve
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
11005
411006
Drain Cooler Valve
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
11006
411007
Drain Pump
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
11007
411008
Drain Pump 2
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
11008
411009
Drain Pump 3
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
11009
411010
Alarm LED
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
11010
411011
Power LED
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
11011
411012
Buzzer
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
12000
412001
System Production Test Done
Unsigned
Scale 1
0 = Inactive
1 = Active
RO
Inactive
12001
412002
Network Control State
Unsigned
Scale 1
0 = Normal
1 = Fault
W
Normal
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
www.neptronic.com
Page | 11
Protocol
Base
Holding
Register
Description
Data Type
Units, Limits, State Texts
Writable
Default
Value
12002
412003
Water Level Low
Unsigned
Scale 1
0 = Inactive
1 = Active
RO
Inactive
12003
412004
Water Level High
Unsigned
Scale 1
0 = Inactive
1 = Active
RO
Inactive
12004
412005
Foam Sensor
Unsigned
Scale 1
0 = NoFoam
1 = Foam
RO
NoFoam
12005
412006
HRL Lock Setpoint
Unsigned
Scale 1
0 = Unlock
1 = Lock
W
Unlock
12006
412007
Notify Alarm
Unsigned
Scale 1
0 = Off
1 = On
W
Off
12007
412008
Notify Warning
Unsigned
Scale 1
0 = Off
1 = On
W
Off
12008
412009
Notify App Msg
Unsigned
Scale 1
0 = Off
1 = On
W
Off
12009
412010
Inhibit Resistive Probe
Unsigned
Scale 1
0 = No
1 = Yes
W
No
12010
412011
Boiler Service Operation
Unsigned
Scale 1
0 = Not Allowed
1 = Allowed
W
Allowed
12011
412012
Boiler Service Due
Unsigned
Scale 1
0 = Off
1 = On
RO
Off
12012
412013
Foam
Unsigned
Scale 1
0 = Ok
1 = Detected
RO
Ok
12013
412014
Water Level Probe Alarm
Unsigned
Scale 1
0 = Ok
1 = Defect
RO
Ok
15000
415001
System Power State
Unsigned
Scale 1
0 = Off
1 = On
W
Off
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
www.neptronic.com
Page | 12
Protocol
Base
Holding
Register
Description
Data Type
Units, Limits, State Texts
Writable
Default
Value
15001
415002
System Log Verbose Level
Unsigned
Scale 1
0 = None
1 = Emergency
2 = Alert
3 = Critical
4 = Error
5 = Warning
6 = Notice
7 = Info
8 = Debug
W
Debug
15002
415003
Modbus Server Units
Unsigned
Scale 1
0 = Metric
1 = Imperial
W
Metric
15003
415004
Control Profile
Unsigned
Scale 1
0 = ExternAnalog
1 = ExternNetwork
2 = InternAnalog
3 = InternNetwork
4 = HRL
5 = Custom
W
ExternAnalog
15004
415005
Modulating High Limit Profile
Unsigned
Scale 1
0 = Disabled
1 = ExternAnalog
2 = ExternNetwork
3 = InternAnalog
4 = InternNetwork
5 = Custom
W
Disabled
15005
415006
Occupancy State
Unsigned
Scale 1
0 = Occupied
1 = Unoccupied
2 = Vacant
3 = Off
RO
Occupied
15006
415007
Room RH Source
Unsigned
Scale 1
0 = None
1 = RoomRH
2 = Network
W
None
15007
415008
Room RH Setpoint Source
Unsigned
Scale 1
0 = None
1 = Internal
2 = ControlInput
W
None
15008
415009
Supply High Limit Reading Source
Unsigned
Scale 1
0 = None
1 = SuppyHLRH
2 = Network
W
None
15009
415010
Supply High Limit Setpoint Source
Unsigned
Scale 1
0 = None
1 = Internal
2 = ControlInput
W
None
15010
415011
Humidity Control Demand Source
Unsigned
Scale 1
0 = None
1 = ControlInput
2 = RoomDemand
3 = Network
W
ControlInput
15011
415012
Humidity Control High Limit Source
Unsigned
Scale 1
0 = None
1 = ControlInput
2 = SupplyHLDemand
3 = Network
W
None
15012
415013
Humidity Control Cutout State
Unsigned
Scale 1
0 = Off
1 = Normal
2 = LowLimit
3 = HighLimit
4 = NoAirFlow
5 = Interlock
RO
Off
SKS4 Steam to Steam Humidifier
Modbus Communication Module User Guide
www.neptronic.com
Page | 13
Protocol
Base
Holding
Register
Description
Data Type
Units, Limits, State Texts
Writable
Default
Value
15013
415014
Boiler Request
Unsigned
Scale 1
0 = None
1 = Reset Alarms
2 = Drain
3 = Reset Counters
4 = Filling
5 = WaterCalib
W
None
15014
415015
Boiler State
Unsigned
Scale 1
0 = Off
1 = Idle
2 = LineRinse
3 = TankRinse
4 = Filling
5 = Draining
6 = Heating
7 = Boiling
8 = Alarm
RO
Off
15015
415016
Boiler Fill Mode
Unsigned
Scale 1
0 = OneShot
1 = Pulsed
W
Pulsed
15016
415017
Boiler Alarm
Unsigned
Scale 1
0 = Normal
1 = FailedPump
2 = FillTimeout
3 = BlockedPiping
4 = HeatTimeout
5 = Overheat
6 = WaterLeak
7 = Service
8 = Foaming
9 = TankBlocked
10 = RefillDelay
RO
Normal
15017
415018
Boiler Idle Tank Rinse On
Unsigned
Scale 1
0 = Off
1 = On
W
Off
15018
415019
Boiler Idle Tank Rinse Off
Unsigned
Scale 1
0 = Off
1 = On
W
Off
15019
415020
Water Probe Auto Calib
Unsigned
Scale 1
0 = None
1 = Once
2 = Always
W
Always
15020
415021
Boiler Startup Tank Rinse
Unsigned
Scale 1
0 = Off
1 = On
W
Off
15021
415022
Water Level Probe Warning
Unsigned
Scale 1
0 = Ok
1 = Calib
2 = Replace
RO
OK
15022
415023
Water Level Probe Failure
Unsigned
Scale 1
0 = None
1 = Capacitive
2 = Resistive
3 = Both
RO
None
Notes
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