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Siemens
Actuators SAX.., SAY.., SAV.., SAL.. for valves
CE1P4040en
Building Technologies
Handling
2018-12-05
3.2.2
Commissioning Modbus RTU
The devices were developed specifically for use with Climatix push-button
configuration as described in document CE1A3975
1)
.
As an alternative, the bus can be configured via the local HMI; see Section
, 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
http://www.siemens.com/bt/download
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
Before change
After change
764
Modbus address
246
12
765
Baud rate
0 = auto
1 = 9600
766
Transmission format
0 = 1-8-E-1
3 = 1-8-N-2
767
Bus termination
0 = Off
0 = Off
768
Bus conf. command
0 = Ready
1 = Load