Endress+Hauser Fieldgate FXA42, Руководство по эксплуатации

Страница: 33 / 118

Fieldgate FXA42 Commissioning
Hauser 33
The values read in from the Datexel server module are in the microampere unit. The values
in the 4 000 to 20 000 µA measuring range must be converted to the current measured
value. The measuring range is linked to the measured pressure range in such a way that a
certain microampere value corresponds to a defined pressure value. The following linear
functional equation is used for this purpose:
f x m x b ( )
= ´ +
A0039591
Here, x corresponds to the incoming measured value in microamperes (µA). m corresponds
to a constant that is calculated according to the following equation:
m
y y
x x
=
-
-
2 1
2 1
A0040990
Where:
• x
2
= upper value of the current range in µA = 20000
• x
1
= lower value of the current range in µA = 4000
• y
2
= measured value at 20000 µA (measured value at 20 mA)
• y
1
= measured value at 4000 µA (measured value at 4 mA)
b corresponds to an additional constant that is calculated according to the following
equation:
b y m x
= - ´
1 1
A0040991
The following diagram for the Web PLC can be created in the editor program on the basis
of this information: