34.Ynrm' Manipulated Variable Standardization - Siemens SIPART PS2 Operating Instructions Manual

8.3.2.7

'34.YNRM' Manipulated variable standardization

Possible settings:
Purpose:
Factory setting:
Figure 8-1
SIPART PS2 with PROFIBUS PA
Operating Instructions, 05/2019, A5E00127926-AC
● MPOS
● FLoW
Use the '32.YA' Manipulated variable limiting Start / '33.YE' Manip‐
ulated variable limiting End (Page 148) parameters to limit the ma‐
nipulated variable. This limitation causes two different scaling types
'MPOS' and 'FLoW' for the display and for the position feedback
through the current output.
The MPOS scale shows the mechanical positions from 0% to 100%
between the upper and lower endstops of the initialization. The
position is not influenced by the '32.YA' Manipulated variable limit‐
ing Start / '33.YE' Manipulated variable limiting End (Page 148)
parameters. The 'YA' and 'YE' parameters are shown in the MPOS
scale.
The FLoW scale is the standardization from 0% to 100% in the
range between the 'YA' and 'YE' parameters. Over this range, the
setpoint w is also always 0% to 100%. This results in a more or less
flow-proportional display and position feedback. The flow-propor‐
tional display and position feedback also results from the use of
valve characteristics.
In order to calculate the control deviation, the setpoint in the display
is also shown in the corresponding scale.
The following uses the example of an 80-mm linear actuator to
illustrate the dependence of the stroke on the scaling as well as on
the 'YA' and 'YE' parameters; see the following figure.
MPOS
YNRM = MPOS or YNRM = FLoW; default: YA = 0 % and YE = 100 %
Parameter assignment
8.3 Description of parameters
149