Vacon 50X User Manual

Contents

Vacon 50X User Manual Manual pdf 27 page image

connections vacon z 2624-hour support +358 (0)40 837 1150 • Email: vacon@vacon.com44.2.5 Single-phase OperationVacon 50X AC drive 230 Vac models are designed for both three-phase and singlephase input power. Ifone of these models is operated with single-phase power, use any two line input terminals. The output ofthe device will always be three-phase.The safe derating of the Vacon 50X series of drives is 50% of the nominal current (hp) rating. Consult thefactory with the particular application details for exact derating by model.4.2.6 Ground Fault Circuit InterruptersVacon 50X drives rated for 230 Vac are not designed to operate with ground fault circuit interrupters (GF-CI). The GFCI breakers are designed for residential use to protect personnel from stray currents toground. Most GFCI breakers will shut off at 5 mA of leakage. It is not uncommon for an AC drive to have30 to 60 mA of leakage.4.2.7 Motor Lead LengthThe distance from the Vacon 50X drive to the motor should not exceed 300 meters. If the leads for motorconnections exceed 30 meters, the motor windings may be subjected to voltage stresses two to threetimes nominal values unless an output filter is utilized. Consult with the motor manufacturer to ensurecompatibility. Line disturbance and noise can be present in motor wiring of any distance. The carrier fre-quency for the drive should also be reduced using parameter 803 (PWM Frequency).Nuisance trips can occur due to capacitive current flow to ground.Some applications can have a restricted lead length because of type of wire, motor type, or wiring place-ment. Consult VACON and the motor manufacturer for additional information.4.2.8 Using Output ContactorsContactors in the output wiring of an AC drive may be needed as part of the approved safety circuit. Prob-lems can arise if these contactors are opened for the safety circuit and the drive is left in run mode ofoperation. When the contactor is open, the drive is in a no-load, no-resistance state, but is still trying tosupply current to the motor. However, when the contactor closes, the drive sees the motor resistance andinstantly demands current. This inrush of current when the contactor closes can fault or cause failure tothe drive.To prevent problems, interlock an auxiliary contact to the drive's Run or Enable circuit to stop the drivewhen the contactor opens. In this way, the drive will be disabled and no inrush will occur when the con-tactor is closed again.