Commissioning Modbus Rtu - Siemens Acvatix SAX Series Basic Documentation

Siemens
Building Technologies
3.2.2

Commissioning Modbus RTU

The devices were developed specifically for use with Climatix push-button
configuration as described in document CE1A3975
As an alternative, the bus can be configured via the local HMI; see Section User
interface, pg. 50.
Check the following during commissioning:
· Bus configuration (address, baud rate, type of transmission and optional
termination). Standard address 255 allows for installation and
commissioning of several actuators simultaneously without mutual
interference.
· The actuator parameters (direction for opening, position limits, position
adjustment etc.) can be read via the Modbus register.
1)
Documents can be downloaded at
Full or partial configuration via bus
The actuators can be configured via bus connection if the settings prior to
commissioning allow for a connection to the Modbus master/programming tool (no
address conflicts and correct baud rates/transmission format settings).
· Full configuration via bus: With a unique Modbus address, a connection can
be established from Modbus master/programming tool following startup by
means of the preset transmission format and baud rate (or auto-baud).
· Partial configuration via bus: If the Modbus address is not unique, it must
first be set to a unique value, either by using the address input with push
button (cf. page 51) or by setting the address to 246 with push button press
> 5s und < 10s (cf. page 50). Full configuration via bus: With a unique
Modbus address, a connection can be established from Modbus
master/programming tool following startup by means of the preset
transmission format and baud rate (or auto-baud)..
With an existing connection, the bus and actuator parameters can be set to target
values via the bus. During write access to the bus parameters,
"1 = Load" must be written to register 768 within 30 seconds to ensure the changes
are not discarded.
Example: The table shows the register values before and after the change via bus
access.
Reg. Name
764
Modbus address
765
Baud rate
766
Transmission format
767
Bus termination
768
Bus conf. command
Actuators SAX.., SAY.., SAV.., SAL.. for valves
Handling
1)
http://www.siemens.com/bt/download
Before change
246
0 = auto
0 = 1-8-E-1
0 = Off
0 = Ready
.
After change
12
1 = 9600
3 = 1-8-N-2
0 = Off
1 = Load
CE1P4040en
2018-12-05
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