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CHAPTER 6 - DETAILED PARAMETER DESCRIPTION
Signal type: set P235 according to transducer signal (4-20 mA,
0-20 mA or 0-10 V).
Set P234 according to the variation range of the used feedback signal
(for more details see parameters descriptions P234 to P240).
Example: suppose the following application:
- Full scale of the transducer (maximum value at the transducer
output) = 25 bar (FS = 25);
- Operation range (range of interest) = 0 to 15 bar (FO = 15).
Considering a safety margin of 10 %, the measuring range of the
process variable must be set to: 0 to 16.5 bar.
Thus: FM = 1.1 x FS = 16.5.
In this manner, the P234 parameter must be set to:
P234 =
FS
x 100 =
25
x 100 = 152
FM 16.5
As the operation range starts at zero, P236 = 0.
Thus, a set point of 100 % represents 16.5 bar, i.e., the operation
range, in percentage is: 0 to 90.9 %.
NOTE!
In most of the cases it is not necessary to set the gain and the offset
(P234 = 100 and P236 = 0.0). Thus, the percentage value of the set
point is equivalent to the percentage value of the full scaleused sensor.
However, if the maximum resolution of the analog input AI1 (feedback)
is desired, set P234 per previous explanation.
Setting of the display indication to the process variable measuring
unit (P040): set P528 according to the full scale of the used transducer
(sensor) and defined P234 (see the following description of parameter
P528)
3) Reference (set point):
Local/remote mode.
Reference source: Set P221 or P222 according to last definition.
4) Speed Limits: Set P133 and P134 according to the application.
Start Up
1) Manual Operation (closed DI):
Display indication (P040): check indication based on external
measurement and on the feedback signal (transducer) at AI1.
Vary the frequency reference (F*) until the desired value of the
process variable is reached.
Only then switch to the automatic mode(inverter willset automatically
P525 = P040), if P536 equal to zero.
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