E+E Elektronik EE850, User Manual

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User Manual EE850 Duct Sensor
INTEGER 16 bit
Parameter Unit Scale
3)
Register number
1)
[DEC] Register address
2)
[HEX]
Read register: function code 0x03
Temperature T
° C 100 4002 0xFA1
° F 50 4003 0xFA2
Relative Humidity % 100 4011 0xFAA
CO
2
(average) ppm 1 4031 0xFBE
CO
2
(raw) ppm 1 4032 0xFBF
Water vapour partial pressure mbar 10 4051 0xFD2
psi 1000 4052 0xFD3
Dew point temperature °C 100 4053 0xFD4
°F 100 4054 0xFD5
Absolute humidity g/m
3
10 4057 0xFD8
gr/ft
3
10 4058 0xFD9
Mixing ratio g/kg 10 4061 0xFDC
gr/lb 10 4062 0xFDD
Specific enthalpy kJ/kg 1 4063 0xFDE
ft lb/lb 1 4064 0xFDF
BTU/lb 1 4065 0xFE0
Frost point temperature °C 100 4066 0xFE1
°F 100 4067 0xFE2
1) Register number starts from 1
2) Register address starts from 0
3) Examples: For scale 100, the reading of 2550 means a value of 25.5. For scale 50, the reading of 2550 means a value of 51.
Communication settings (INTEGER 16 bit)
Parameter
Register number
1)
[DEC] Protocol address
2)
[HEX]
Write register: function code 0x06
Slave ID (Modbus address)
3)
1 0x00
Modbus protocol settings
4)
2 0x01
1) Register number starts from 1.
2) Protocol address starts from 0.
3)
If the ID is set via DIP switch the response will be NAK.
4) For Modbus protocol settings see Application Note Modbus AN0103 (available on www.epluse.com/EE850 ).
INFO (read register)
Parameter
Register number 1) [DEC] Protocol address 2) [HEX]
Read register: function code 0x03 / 0x04
Serial number (as ASCII) 1 0x00
Firmware version 9 0x08
1) Register number starts from 1.
2) Protocol address starts from 0.
3.6 Modbus RTU Example
Example of MODBUS RTU command for reading the CO
2
(float value) CO
2
= 1288,34375 ppm from the
register 0x424
Device EE850; slave ID 67 [0x43]
Reference document, chapter 6.3: http://www.modbus.org/docs/Modbus_Application_Protocol_V1_1b3.pdf
Request [Hex]: 43 03 04 24 00 02 8A 12
Modbus ID
address
Function
code
Starting
address Hi
Starting
address Lo
No. of
register Hi
No. of
register Lo
CRC
Request [Hex]: 43 03 04 24 00 02 8A 12
Response [Hex]: 43 03 04 0B 00 44 A1 68 AB
Modbus ID
address
Function
code
Byte count Register 1
value Hi
Register 1
value Lo
Register 2
value Hi
Register 2
value Lo
CRC
Response [Hex]: 43 03 04 0B 00 44 A1 68 AB