Siemens WZU-485E-MOD - Modbus Data Structure and Reading; Modbus Register Data Format; Modbus Data Reading Procedures

WZU-485E-MOD Subject to change without prior notice 4
8. Modbus description
Unless otherwise indicated, all values are in binary format. 2-byte values (signed), and 4-byte values (unsigned), are used.
Note: The module only transmits absolute values of the meter’s parameters.
Data format of a complete meter readout
Register
Number
Data
Address
Value
Name Value
No. of
Bytes
Description
0x40002
1
Tf
Temperature hot side
2
0.01 °C
0x40003
2
Tr
Temperature cold side
2
0.01 °C
0x40004
3
dT
Temperature difference
2
0.01 K
0x40005
4
Q
Actual flow
4
0.001 m³/h
0x40007
6
P
Actual power
4
0.01 kW
0x40009
8
Ecold
Accumulated cold energy (eq. tariff register 1)
4
format and unit according to header
0x4000B
10
Time
Date and time
4
M-Bus type F
0x4000D
12
F
Info code F
2
Meter Error (see table 2)
0x4000E
13
Header
Module info
2
Units and formats (see table 3)
0x4000F
14
E
Accumulated energy (Standard register)
4
format and unit according to header
0x40011
16
V
Accumulated volume
4
format according to header m
3
0x40013
18
N
Serial number
4
0x40015
20
EM
Monthly value - Energy on set day
4
format and unit according to header
0x40017
22
VM
Monthly value - Volume on set day
4
format according to header m
3
0x40019
24
A1
Pulse input 1 accumulated (not used)
4
Not used
0x4001B
26
A2
Pulse input 2 accumulated (not used)
4
Not used
0x4001D
28
I1
Pulse value input 1 (not used)
4
Not used
0x4001F
30
I2
Pulse value input 2 (not used)
4
Not used
0x40021
32
N1
Serial number A1
4
0x40023
34
N2
Serial number A2
4
0x40025
36
Tariff register 1
4
format and unit according to header
0x40027
38
Tariff register 2
4
format and unit according to header
0x40029
40
Tariff register 3
4
format and unit according to header
Table1: Available Modbus registers
Data reading
 The module only responds to data requests with function code 03 (read holding registers).
 Meter values are available at data addresses 1 – 40.
 Any data address from the range can be chosen as a starting point.
 The module does not check the completeness of the variables it sends.
 After receiving a data request, the module reads new data from the meter within 5 seconds.
 After a data request with the broadcast address “0“, the module reads new data from the meter, but sends no message.
 The module does not return exception responses to invalid data requests.