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

Parameter assignment
9.4 Description of parameters
9.4.2.9

'37.YNRM' Standardization of manipulated variable

Possible settings:
Purpose:
Factory setting:
Figure 9-3
164
• MPOS
• FLoW
Use the '35.YA' Start of manipulated variable limit / '36.YE' End of
manipulated variable limit (Page 163) parameters to limit the ma-
nipulated variable. This limitation causes two different scaling
types 'MPOS' and 'FLoW' for the display and for the position feed-
back 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 '35.YA' Start of manipulated varia-
ble limit / '36.YE' End of manipulated variable limit (Page 163)
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 'IY'. The flow-
proportional display and position feedback 'IY' also result when
using valve characteristics.
In order to calculate the control deviation, the setpoint in the dis-
play 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 %
SIPART PS2 with and without HART
Operating Instructions, 02/2016, A5E00074631-AB