15
Service manual
www.microphase.eu
Mini Dc
3.2
Setting with tachogenerator
feedback
RDT (Kohm) = Kdt * N * 9,7
1000 * Vref
- 7,9
Example: Brush DC motor with the tachogenerator costant Kdt=10V/KRPM, max. speed 2500RPM at
10V of speed reference. The result is below:
RDT (Kohm) = 10 * 2500 * 9,8
1000 * 10
- 7,9 = 16.6 Kohm
Insert the commercial value resistance 18Kohm. Prefer resistance with 1% tolerance.
Note:
RDT is the value of resistor expressed in Kohm with a power rating of 1/8 or 1/4w.
Kdt is the tachogenerator costant V/KRPM
N is the max speed express in RPM.
Vref is the max v/-REF reference express in Volts.
To calculate RDT resistor, please use the following formula:
Once the resistor RDT is inserted, proceed with final speed adjustment.
Operate using trimmer SPEED on the front of the drive. With Clockwise Rotation the speed increases.
With Counter Clockwise Rotation the speed decreases. The Range of regulation is about +/- 20%.
RDT resistor calculations
In this configuration, the drive must set with the following Dip Switch and below internal setting:
DS1 Switch set for:
- Tachogenerator feedback
- Ramp time disabled
- Standard Dynamic constant
Note: On the adjustement zone are not
considered here the other components used
to determine other calibrations "for example.
Calibration current rating etc.".
DS1
7 6 5 4 3 2 1
DS1 SWITCH
ADJUSTEMENT PADS
