Kübler A40 Instructions D'utilisation page 10

Trimmpoten-
tiometer Pe
Potentiometer
Trimmpoten-
tiometer Po
Fig. 9: Adjusment of the trimmpotentiometer
4...20 mA (Standard)
• Trimmpotentiometer's Po is used to adjust a current
of 4 mA to extension length of 0 to 15% of the
measurement range.
• Trimmpotentiometer's Pe is used to adjust a current
of 20 mA to extension length of 85% to 100% of
the measurement range.
The smallest available transducer range, in which
4 to 20 mA are delivered, is hence 15% to 85% of the
measurement range.
Current
20 mA
4 mA
0
Fig. 10: Aligment
Alignment
1. Move axis to start position.
2. Turn left potentiometer (Po) until start value
(4 mA) is measured.
3. Move axis to end position.
4. Turn right potentiometer (Pe) until end value
(20 mA) is measured.
The steps 1 to 4 are to be repeated until the values
are counterbalanced.
5.3 Alignment of the R/U-transformers (0...10 V)
If the device is equipped with a resistance-voltage
converter, tehen the potentiometer resistance is
4
converted into a voltage of 0 to 10 VDC. Connection
is via three-wire technology.
At the time of delivery, the instrument transformer
is preset to the standard value 0 V output voltage
(Po) and the end value 10 V output voltage (Pe).
The output of the instrument transformer should
be wired against 0V with a resistor 2 to 10 KΩ to
enable the initial value of 0 V to be set. However,
the output current of 10 mA won't be exceeded in
the end position (10 V). By means of the trimming
potentiometer Pe (see fig. 12), the final value can
be adjusted to the actual final position of the ap-
plication.
Setting the instrument transformer
When the screws (1) are removed and the cover
(2) opended, the trimming potentiometers Pe can
be accessed. Since it is SMD designed, it should
be set up cautiously. An output voltage of 10 V with
an extension position of 60 to 100% of the maximum
encoder extension length can be set.
Measuring range ≤ 1000 mm


(Pe)
Fig. 11: Adjustment of the trimmpotis 0...10 V
Measuring range > 1000 mm
(Po)
Trimmpoten-
tiometer Pe
Distance
Potentiometer
Fig. 12: Adjustment of the trimmpotentiometer