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Elektronik GmbH
Page 26 of 45
POS-124-*-PDP-1121
13.02.2013
5.2.17
AIN (Analogue input scaling)
Command
Parameters
Unit
Group
AIN:I
A
B
C
X
i= X1|X2
a= -10000… 10000
b= -10000… 10000
c= -700… 10000
x= V|C
-
-
0.01%
-
STD
This command can be used to scale the individual inputs. The following linear equation is used for
scaling.
= ∙
−
The “
c” value
is the offset (e.g. to compensate the 4 mA in the case of a 4… 20 mA input). The variables
a
and
b
define the gain factor.
e.g.: 2.345 correspond to:
a
= 2345,
b
=1000
The internal measuring resistor for measuring the current (4… 20 mA) is activated via the
x
value and the
evaluation switched over accordingly.
Typical settings:
Command
Input
Description
AIN:X1 1000 1000 0 V
0… 10V
Range: 0… 100%
AIN:X1 10 8 1000 V
OR
AIN:X1 1000 800 1000 V
1… 9V
Range: 0… 100%; 1 V = 1000 used for the offset and gained by 10 /
8 (10V divided by 8 V (9V -1V)
AIN:X1 10 4 500 V
OR
AIN:X1 1000 400 500 V
0,5… 4,5V
Range: 0… 100%; 0,5 V = 500 used for the offset and gained by 10 /
4 (10V divided by 4 V (4,5V -0,5V)
AIN:X1 20 16 2000 C
OR
AIN:X1 2000 1600 2000 C
4… 20mA
Range: 0… 100%
The offset will be compensated on 20% (4 mA) and the signal (16 mA
= 20mA – 4 mA) will be gained to 100% (20 mA).
