Special use
TM 5-3895-374-24-1
Unidirectional speed
Measurement of the actual motor speed with a tachogenerator allows the speed to be regulated
regulation
This being the case, automatic slip compensation depending on the load incorporated in the
ALTIVARATV-452 is cancelled and replaced by the speed regulation loop
When the motor is used in one direction only, the tachogenerator can be connected to the speed
controller via a simple adaptation circuit
Utilization safety measures
- Comply with the polarities shown for the tachogenerator connections
- The SN+ terminal voltage must be < + 5V
- Link PN to OVN
- Use the controller in the forward direction only (terminal FW)
- Connect the tachogenerator using twisted cables
CAUTION: neither this adaptation circuit, nor that of the tachogenerator are isolated from the
supply
Accuracy + 0,1 % of the maximum speed for - a torque variation from 0,2 Tn to Tn,
- a speed range from 1 to 50/60
Calculation of R1 calculate the maximum voltage provided by the tachogenerator
EXAMPLE motor 1500 rpm at 50 Hz
tachogenerator 0,06 V/rpm \ U = 0,06 x 1500 x 67 = 120,6 V
frequency range 67 Hz
50
R2 slide in median position R1 = 1,5 x 120,6 - 2 = 34 kW Use 33 kW
5
Adjustments
Connect a voltmeter to the tachogenerator terminals
Adjust the R2 potentiometer to its minimum setting, in fully anti-clockwise position
Start the motor and set the maximum speed using the reference potentiometer
Turn R2 clockwise until the corresponding voltage is obtained
(page 3-211)
