E+E Elektronik EE741 User Manual page 23

NOTICE
For obtaining the correct floating point values, both registers have to be read within the same reading
cycle. The measured value can change between two Modbus requests, exponent and mantissa may get
inconsistent then.
INFO
The Modbus function codes mentioned throughout this document shall be used as described in the
MODBUS APPLICATION PROTOCOL SPECIFICATION V1.1b3, chapter 6:
www.modbus.org/docs/Modbus_Application_Protocol_V1_1b3.pdf
Communication settings (INT16)
Parameter
Write register: function code 0x06
4)
Modbus address
Modbus protocol settings
Device information (INT16)
Parameter
Read register: function code 0x03 / 0x04
Serial number (as ASCII)
Firmware version
Sensor name
1) Register number (decimal) starts from 1.
2) Register address (hexadecimal) starts from 0.
3) Number of registers
4) For Modbus address and protocol settings see Application Note Modbus AN0103 (available at www.epluse.com/ee741).
PLEASE NOTE
Bus termination resistor:
Bus termination is required for the last flow sensor in a Modbus RTU network. The 120 Ω termination resistor
is located behind the blind of the USB port and can be switched on and off (see Fig. 17).
Fig. 17 Bus termination resistor
Register number
1
4)
2
Register number
1
9
10
1)
[Dec] Register address
00
01
1)
[Dec] Register address
00
08
09
User Manual EE741
2)
[Hex] Size
1
1
2)
[Hex] Size
8
1
8
Inline Flow Sensor for Compressed Air and Gases | 23
3)
3)