Siemens SIPART PS2 Operating Instructions Manual page 111

Procedure
1. Switch to "Diagnostics" mode.
2. Select the diagnostics parameters.
3. Press the three buttons of the positioner at the same time for at least 2 seconds.
4. Activate the setting function. Press the
The modified diagnostics values are effective immediately. The effects on the controller
results can then be tested.
In order to optimize the controller data, change the values of the diagnostics parameters
listed below.
Diagnostics parameters '23.IMPUP' Impulse length UP / '24.IMPDN' Impulse length DOWN
You can use these diagnostics parameters to determine the smallest impulse lengths for
each actuating direction. The actuator is then moved with these lengths. The optimum value
depends in particular on the volume of the actuator. Small values lead to small controller
increments and frequent activation of the actuator. Large values are advantageous for large
actuator volumes.
Note
Controller increments
• There is no movement if the values are too small.
• Large controller increments also lead to large movements with small actuators.
Diagnostics parameters '28.SSUP' Slow step zone UP / '29.SSDN' Slow step zone DOWN
The slow step zone is the area of mean control deviation. For more information on the slow
step zone, refer to the section "Mode of operation (Page 28)".
Select small values to achieve high speeds of shifting even with small control deviations.
Select large values to reduce overshoots particularly in case of large changes in the setpoint.
NOTICE
Overshoots or too low speeds of shifting
Too small values can result in overshoots.
• Enter a higher value.
Too large values result in too slow speeds of shifting near the adjusted status.
• Enter a smaller value.
SIPART PS2 with and without HART
Operating Instructions, 02/2016, A5E00074631-AB
or button for at least 5 seconds.
Operating
6.2 Operating modes
111