VEGA VEGASCAN 850 Modbus signal output - Manual (Page 8)

8 Modbus signal output VEGASCAN 850
Start
Slave
ad-
dress
Func-
tion
code
Address of the
1. register
word
Number of
register
words
Error
Check
End
No. of
bytes
Value
range
Meaning
Structure of the measured value enquiry Modbus master to VEGACOM 557
RTU enquiry telegram acc. to measured values (function code 04)
3 ... 4 1 1 2 2 2 3 ... 4
Closed level 1 .. 247 04 0 ... 65.509 1 ... 127 CRC Closed level
0x01 0x04 0x00 0x1C 0x00 0x02 0xXX 0xXX
Start
Func-
tion
code
No.of
data
bytes
Error
Check
End
No. of
bytes
Value
range
Meaning
Structure of the answer VEGACOM 557 to Modbus master
RTU answer telegram (function code 04)
3 ... 4 1 1 1
2 bytes per
register word
2 3 ... 4
Closed level 1 .. 247 04
2 ....
255
0 ... 255 per byte CRC Closed level
0x01 0x04 0x04 0x01 0x4A 0x00 0x00 0xXX
Data (DCS values)
0xXX
DCS value 15 of VEGASCAN:
Status:
0x00
Meas. unit:
0x00
Measured value:
0x014A = 3.30%
Data transmission with Modbus RTU
Setting of parameters of VEGASCAN 850 in RTU mode
Various parameters of VEGASCAN can be enquired measurement loop-related.
The following list gives an overview of the parameters involved:
Parameter name possible access mode
Integration time reading writing
Scaling (0 %) reading writing
Scaling (100 %) reading writing
The enquiry or modification of parameters via the Modbus is made with the function codes 16
(= Preset Multiple Registers) and 04 (Read Input Registers).
Slave
ad-
dress