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Functions/operations using PROFIBUS PA
11.2 Acyclic data transfer
The above target modes are effective when the positioner is in the automatic mode (AUT). If
the positioner is in the manual mode (MAN), they are effective only after an on-site
switchover to the automatic mode (AUT).
These target modes are saved in the positioner in the power failure-safe manner.
Automatic mode
As long as the positioner is not integrated into the cyclic service as a slave, SIMATIC PDM
can be used to send a setpoint to it in a cyclic manner.
Configure the following settings:
1. Go to the "Operating mode" tab.
2. Set the target mode to "Automatic".
3. Enter a value between 0 and 100% for the desired setpoint, quality as "Good" and the
status as "OK".
4. Transfer these settings to the positioner.
The positioner is controlled using the desired setpoint until a cyclic master starts
communication with a slave or you switch over the positioner to the "Manual" mode on-site.
Note
Note that the positioner responds with the "Poor" quality and the "Constant value" status
after sending the data.
If you exit this target mode and no other master sends a setpoint to the positioner, it is
controlled using the configured fail-safe value after the set monitoring time expires.
Manual mode
You can use SIMATIC PDM to send a setpoint to the positioner even when cyclic
communication is active. You must have priority over the cyclic master.
Configure the following settings:
1. Go to the "Operating mode" tab.
2. Set the target mode to "Manual".
3. Enter a value between 0 and 100% as a starting value, quality as "Good" and the status
as "OK".
4. Transfer these settings to the positioner.
The positioner is now controlled using the desired starting value and reports this manual
mode through "MM" on the digital display.
Note that the starting value entered in the manual mode is directly written in the starting
block of the positioner without scaling.
You can switch the positioner to the manual mode on-site and move the actuator using
buttons. The setpoint is tracked as per the current actual value. The manual mode and the
current position are retained after switching back to the automatic mode.
After a power failure, the positioner is controlled in the manual mode depending on the
direction of action of the actuator using the value set in the "YA" or "YE" parameters.
180
SIPART PS2 with PROFIBUS communication
Operating Instructions, 09/2007, A5E00127926-07
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