company news

1. Insulation inspection of motor

When firstly using motor, using motor again after putting for a long time and regularly checking motor, insulation inspection of motor is essential to prevent damaging frequency convertor due to invalid insulation of motor winding. During insulation inspection, separate motor wire from frequency convertor. 500V voltage-type tramegger is suggested and ensure measured insulation resistance≥5MΩ.

2. Thermal protection of motor

If selected motor does not match with rated capacity of frequency convertor, especially if rated power is larger than that of frequency convertor, please adjust related parameter values of motor protection or install thermal relay in front of motor for protection.

3. Operation above power frequency

The frequency convertor offers output frequency at 0Hz～3200Hz. If users need to operate at above 50Hz, please consider the tolerance of mechanical device.

4. Vibration of mechanical device

Mechanical resonance point of load device may exist at certain output frequency of frequency convertor, and hopping frequency parameter can be set to avoid.

 5. About heating and noise of motor

Output voltage of frequency convertor is PWM wave containing certain harmonic, so temperature rise, noise and vibration of motor will slightly increase when comparing with power frequency operation.

6. Voltage-sensitive parts or capacitance of improving power factor exist on output side

Output of frequency convertor is PMB wave. If capacitance of improving power factor or voltage dependent resistor for thunder prevention is installed on output side, instantaneous over current and even damage of frequency convertor can be caused easily. Please do not use.

7. Switching devices such as contactor for input and output terminals of frequency convertor

          If contactor is installed between power and input terminal of frequency convertor, this contactor is not allowed to control the start and stop of frequency convertor. If this contactor is required to control the start and stop of frequency convertor, the interval should be not less than one hour. Frequent charging and discharging will easily reduce the lifespan of capacitor within frequency convertor. If switching devices such as contactor are installed between output terminal and motor, ensure the operation of frequency convertor without output, otherwise module damage may occur easily.

8. Use beyond rated voltage value

It’s not suitable to use VFD-200G series frequency convertor beyond operating voltage range allowed by the manual, otherwise device damage may be caused. If necessary, please use corresponding voltage boosting or dropping equipment for voltage transformation.

9. Three-phase input changes to be two-phase input

Do not change three-phase frequency convertor to be two-phase, otherwise fault or damage may occur.

10. Lightening impulse protection

          There’s lightening stroke over-current protection device in frequency convertor, so it has certain self-protection ability for inductive thunder. If lightening stroke is frequent in the place of client, additional protection in front of frequency convertor is essential.

11. Altitude and derating use

In the region with altitude exceeding 1,000m, the heat dissipation effect of frequency convertor weakens due to thin air, so it’s necessary to derate for use. Please contact our company for consultation.