E+E Elektronik EE260, User Manual

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User Manual EE260 Heated Humidity and Temperature Probe for Meteorological Applications
INTEGER 16 bit:
Parameter Unit Scale 3) Register number 1) [Dec] Register address 2) [HEX]
Read register: function code 0x03 / 0x04
Temperature T
°C 100 4002 0xFA1
°F 50 4003 0xFA2
°K 50 4005 0xFA4
Relative humidity RH, Uw % RH 100 4011 0xFAA
Water vapour partial pressure e
mbar 10 4051 0xFD2
psi 1000 4052 0xFD3
Dew point temperature Td
°C 100 4053 0xFD4
°F 100 4054 0xFD5
°K 100 4074 0xFE9
Wet bulb temperature Tw
°C 100 4055 0xFD6
°F 100 4056 0xFD7
°K 100 4073 0xFE8
Absolute humidity dv
g/m³ 10 4057 0xFD8
gr/ft³ 10 4058 0xFD9
Mixing ratio r
g/kg 10 4061 0xFDC
gr/lb 10 4062 0xFDD
Specific enthalpy h
kJ/kg 1 4063 0xFDE
ft lbf/lb 1 4064 0xFDF
BTU/lb 1 4065 0xFE0
Frost point temperature Tf
°C 100 4066 0xFE1
°F 100 4067 0xFE2
°K 100 4075 0xFEA
Volume concentration Wv
ppm 0.1 4076 0xFEB
% 1000 4078 0xFED
‰ 100 4079 0xFEE
Saturation vapor pressure
above water ew
mbar 100 4111 0x100E
psi 100 4112 0x100F
Saturation vapor pressure
above ice ei
mbar 100 4113 0x1010
psi 100 4114 0x1011
Ice bulb temperature Ti
°C 100 4119 0x1016
°F 100 4120 0x1017
°K 50 4121 0x1018
Specific humidity qv
g/kg 10 4124 0x101B
gr/lb 10 4125 0x101C
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.
5.4 Modbus Message Example
Example of Modbus RTU command for reading the temperature (float value) T = 24.625015 °C
from the register 0x3EA
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Device EE260; slave ID 235 [0xEB]
Reference document, chapter 6.3: www.modbus.org/docs/Modbus_Application_Protocol_V1_1b3.pdf
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See Application Note Modbus AN0103 (available on www.epluse.com/EE260 )
Modbus ID
address
Function
code
Starting
address Hi
Starting
address Lo
No. of
register Hi
No. of
register Lo
CRC
Request [Hex]: EB 03 03 EA 00 02 F3 71
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]: EB 03 04 00 08 41 C5 C0 3C