SGP/1
Adjustment and alignment English 31
2
1
2
Allen screws
Drive's housing
1
Fig. 15: Changing the position of the cabele or connector outlet
6 Adjustment and alignment
6.1 Potentiometer setting
When correctly connected and switched on, the unit displays the current actual value.
The measuring range of the potentiometer is matched to the total pull-out length of the wire. Ex works value 0 Ω is preset for the pull-out length of
0 mm (wire completely pulled in).
6.2 Alignment of the R/I transformer (MWI)
If the device is equipped with a resistance-current converter, then the potentiometer resistance is converted into a current of 4 to 20 mA. The measuring current is also used for feeding the instrument transformer.
Ex-works, the instrument transformer is aligned to standard values of the potentiometer. Initial position 4 mA (Po), corresponds to 0 mm pull-out length (completely retracted). End position 20 mA (Pe) corresponds to maximum pul-out length (completely pulled out).
Via two trim potentiometers Pe 2 and Po 1
(see Fig. 16
) these values can be adjusted to the application's actual start and end position.
32
SGP/1
Adjustment and alignment English
Setting the instrument transformer
After releasing the hood snap (see chapter 4.3
), the trimming potentiom-
eters can be accessed.
2
1
2
3
Trimming potentiometer Po
Trimming potentiometer Pe
10-turn-potentiometer
3
1
Fig. 16: Setting the trimming potentiometers MWI
• Trim potentiometer Po is used to adjust a current of 4 mA to extension length of 0 to 15 % of the maximum encoder extension length.
• Trim potentiometer Pe is used to adjust a current of 20 mA to extension length of 90 to 100 % of the maximum encoder extension length.
The smallest available transducer range, in which 4 to 20 mA are delivered, is hence 15 to 90 % of the measurement range.
Alignment (
Fig. 17
)
1. Move the machine to the start position.
2. Turn potentiometer Po 1 until start value 4 mA is measured.
3. Move the machine to the end position.
4. Turn potentiometer Pe 2 until end value 20 mA is measured.
The steps 1 to 4 are to be repeated until the values are counterbalanced
(iterative alignment).
Current
20 mA (Pe)
4 mA
0
Fig. 17: Aligment
(Po)
Distance
SGP/1
Adjustment and alignment English 33
6.3 Alignment of the R/U transformer (MWU)
If the device is equipped with a resistance-voltage converter, then the potentiometer resistance is converted into a voltage of 0 to 10 V DC. Connection is via three-wire technology.
Ex-works, the instrument transformer is aligned to standard values of the potentiometer. Initial position 0 V (Po), corresponds to 0 mm pull-out length (completely retracted). End position 10 V (Pe) corresponds to maximum pull-out length (completely pulled out).
The output of the instrument transformer should be wired against GND with a transistor 2 to 10 kΩ, in order that the initial value of 0 V will be reached. However, the output load should be dimensioned in a way that avoids a higher output current than 15 mA in the end position (10 V).
By means of the trim potentiometer Pe 1
(see Fig. 18
), this value can be adjusted to the actual final position of the application.
Setting the instrument transformer
After releasing the hood snap (see chapter 4.3
), the trimming potentiom-
eters can be accessed.
1
1 Trimming potentiometer Pe
2 10-turn-potentiometer
2
Fig. 18: Setting the trimming potentiometers MWU
• An output voltage of 10 V with an extension position of 60 to 100 % of the maximum encoder extension length can be set.
Alignment
1. Move axis to end position.
2. Turn potentiometer Pe 1 until an output voltage 10 V is measured.
