Endress+Hauser Proline Promass 84 MODBUS RS485 Operating Instructions Manual page 45

Proline Promass 84 MODBUS RS485
!
Endress+Hauser
Response time
The response time when accessing the data area (register addresses 5051 to 5081) is typically
between 3 and 5 ms.
Note!
It may take longer for a command to be executed in the device. The data is not updated until the
command has been executed. Especially write commands are affected by this!
Example
The following device parameters should be grouped via the auto-scan buffer and read out by the
master with just one request telegram:
• Mass flow → Register address 2007
• Temperature → Register address 2017
• Totalizer 1 → Register address 2610
• Actual system condition → Register address 6859
1. Configuration of the scan list
• With the local operation or a configuration program (via the function matrix):
BASIC FUNCTION block → MODBUS RS485 function group → SCAN LIST REG. function
→ Entry of the address 2007 under SCAN LIST REG. 1
→ Entry of the address 2017 under SCAN LIST REG. 2
→ Entry of the address 2610 under SCAN LIST REG. 3
→ Entry of the address 6859 under SCAN LIST REG. 4
• Via the MODBUS master (the register addresses of the device parameters are written to the
registers 5001 to 5004 via MODBUS):
1. Write address 2007 (mass flow) to register 5001
2. Write address 2017 (temperature) to register 5002
3. Write address 2610 (totalizer 1) to register 5003
4. Write address 6859 (actual system condition) to register 5004
Slave
Register Value
Fig. 31: Configuration of the scan list via the MODBUS master
MODBUS RS485
Autoscan Buffer
Data Data
Value Register
Scan List
Register
No.
1 5001
2 5002
3 5003
4 5004
Operation
Master
Data
Register
2007
2017
2610
6859
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