User`s guide

Appendix A _________________________________________________________ Modbus Reference
VAISALA ________________________________________________________________________ 61
Modbus Register Map
Table 21 Modbus Register Map
Logical
Address
(decimal)
PDU Address
(hexadecimal)
Register Description
Data
Format
Register
Type
Notes
5
00 04
T
(measured)
LSW
MSW
32-bit
float
read-only
°C
6
00 05
7
00 06
T
d/f
(measured)
LSW
MSW
32-bit
float
read-only
°C
8
00 07
11
00 0A
T
d/f
(atm)
(measured)
LSW
MSW
32-bit
float
read-only
°C
12
00 0B
21
00 14
H
2
O (measured)
LSW
MSW
32-bit
float
read-only
ppm
v
22
00 15
45
00 2C
P (measured)
LSW
MSW
32-bit
float
read-only
bara
46
00 2D
47
00 2E
ρ (measured)
LSW
MSW
32-bit
float
read-only
kg/m
3
48
00 2F
49
00 30
P
norm
(measured)
LSW
MSW
32-bit
float
read-only
bara
50
00 31
513
02 00
Fault status
16-bit
boolean
read-only
1 = no errors
514
02 01
Online status
16-bit
boolean
read-only
1 = online data
available
516
02 03
Error code
LSW
MSW
32-bit bit
field
read-only
0 = no errors
517
02 04
775
03 06
Molar mass of other
gas (set value)
LSW
MSW
32-bit
float
read/write
kg/mol
776
03 07
781
03 0C
Gas mixing ratio
(set value)
LSW
MSW
32-bit
float
read/write
0 …100 % of
SF
6
782
03 0D
783
03 0E
Pressure
normalization
temperature (set
value)
LSW
MSW
32-bit
float
read/write
-100 … 100°C
784
03 0F
1283
05 02
Automatic purge on/off*
16-bit
boolean
read/write
1= automatic
purge on
1284
05 03
Start-up purge on/off*
16-bit
boolean
read/write
1 = start-up
purge on
1285
05 04
Purge in progress*
16-bit
boolean
read/write
1 = purge in
progress, write
1 for manual
start
1537
06 00
Address
16-bit
integer
read/write
1…255 (1 …
247 allowed in
Modbus)
*Device specifications are valid only if purge functions are kept enabled. Do not modify registers 1283, 1284,
and 1285. Regular purge is needed to guarantee accurate measurements. Modify only if instructed to by Vaisala.
PDU address
Actual address bytes used in a Modbus Protocol data unit
LSW
Least significant word (bits 15 … 0)
MSW
Most significant word (bits 31 … 16)
16-bit integer
Numeric value in range 0 … 65535
16-bit boolean
Numeric value, 0 or 1
32-bit bit field
32 individual values, each 0 or 1
32-bit float
Floating point, IEEE 754 format
read-only
Register value cannot be changed with Modbus functions
read/write
Register value can be changed with Modbus functions