Vaisala MGP261, Руководство пользователя

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Registers are numbered in decimal, starting from one. Register
addresses in actual Modbus messages (Modbus Protocol Data Unit (PDU) are in
hexadecimal and start from zero. Subtract 1 from the register number presented
in this manual to get the address used in the Modbus message. For example, the
register number 769 (Modbus address) corresponds to address 0300
hex
in the
Modbus message.
CAUTION!
Accessing unavailable (temporarily missing) measurement data does not generate an
exception. “Unavailable” value (a quiet NaN for floating point data or 0000
hex
for integer data)
is returned instead. An exception is generated only for any access outside the applicable
register ranges.
A.1.1 Measurement Data
Table 13 Modbus Measurement Data Registers (Read-Only)
Register
Number
(Decimal) Address
(Hexadecimal) Register Description Data Format Unit
Floating Point Values
1 0000
hex
Methane (CH
4
)
concentration
32-bit float ppm
v
0001
hex
3 0002
hex
Methane (CH
4
)
concentration, dry basis
32-bit float ppm
v
0003
hex
5 0004
hex
Carbon dioxide (CO
2
)
concentration
32-bit float ppm
v
0005
hex
7 0006
hex
Carbon dioxide (CO
2
)
concentration, dry basis
32-bit float ppm
v
0007
hex
9 0008
hex
Water (H
2
O)
concentration
32-bit float ppm
v
0009
hex
11 000A
hex
Water (H
2
O)
concentration, dry basis
32-bit float ppm
v
000B
hex
MGP261 User Guide
Appendix A.
Modbus Registers
A.1 Modbus Registers
M212273EN-A
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