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5.2.1 Correction of the analogue current output
The minimum of analogue current output is 4 mA. A lower current is not possible. When calibrating, the
zero-point current has to be set to 4,1 mA with the potentiometer “NULLPUNKT”. Now the range of the
current output can be set to 16 mA by using the potentiometer P-03. With an adjusted range of 16 mA
the output has to read 20,1 mA at maximum load. After adjusting the range the zero shall be set back
to 4,0 mA.
5.2.2 Calculation of amplification determing resistor
The amplification is:
Gtotal = Gdifferential amplifier x Goutput stage
The amplification of the output stage is adjustable with the potentiometer P-02 (GAIN). The
adjustable range is:
G
output stage
=
9,5 … 10,5
Calculation of the coarse amplification resistor RG (applies for 10 Volts output):
G
differential amplifier
=
1000 mV
Exc. (V) x Signal (
mV
V
)
R
G
=
50 kOhm
(G differential amplifier –1)
Example:
Transducer:
2,5000 mV/V (0,0025V/V)
Excitation:
10,000 V
R
G
=
50 kOhm
(
1V
10 V x 0,0025 V
-1)
=
1282 Ohm
