E+E Elektronik EE360, User Manual

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User Manual EE360
Moisture in Oil Sensor | 24
Communication settings (INT16)
Parameter
Register number
1)
[Dec] Register address
2)
[Hex]
Write register: function code 0x06
Modbus address
1 0x00
Modbus protocol settings
3)
2 0x01
1) Register number starts from 1.
2) Protocol address starts from 0.
3) For Modbus protocol settings see Application Note Modbus AN0103 (available at www.epluse.com/ee360 ).
Tab. 9 EE360 registers for device setup
5.6 Modbus RTU Example
The EE360’s Modbus address is 231 [E7 in HEX].
Please refer to
▪
MODBUS APPLICATION PROTOCOL SPECIFICATION V1.1b3, chapter 6:
www.modbus.org/docs/Modbus_Application_Protocol_V1_1b3.pdf
▪
E+E Application Note Modbus AN0103 (available at www.epluse.com/ee360 )
Read the temperature (FLOAT32) T = 26.953624 °C from the register 0x3EA :
Master (e.g. PLC) EE360
Request [Hex]:
Modbus
address Function
code
Starting
address Hi
Starting
address Lo
Qty. of
registers Hi
Qty. of
registers Lo
CRC
E7 03 03 EA 00 02 F3 BD
Response [Hex]:
Modbus
address Function
code
Byte
count
Register 1
value Hi
Register 1
value Lo
Register 2
value Hi
Register 2
value Lo
CRC
E7 03 04 A1 06 41 D7 CE 0E
Tab. 10 Example temperature query
Decoding of floating point values:
Floating point values are stored according to IEEE754. The byte pairs 1, 2 and 3, 4 are transformed as follows
(numbers taken from T reading Modbus request/response example above):
Modbus response [Hex]
Register 1 Hi Register 1 Lo Register 2 Hi Register 2 Lo
A1 06 41 D7
MMMMMMMM MMMMMMMM SEEEEEEE EMMMMMMM
Fig. 18 Modbus response
IEEE754
Register 2 Hi Register 2 Lo Register 1 Hi Register 1 Lo
41 D7 A1 06
0100 0001 1101 0111 1010 0001 0000 0110
SEEE EEEE EMMM MMMM MMMM MMMM MMMM MMMM
Decimal value: 26.953624725341796875
Fig. 19 Data representation according to IEEE754