3-6
(9) Pass the power cable through a metal tube or a metal conduit for shielding, and connect a ground
wire to the outer surface of the tube.
(10) Limit the fluctuations of the supply voltage within ±10% of the rated voltage, and also limit the
fluctuations of the frequency within -5% to +3% of the rated value. Although you can run the pump
in these ranges, avoid continuous operation if the voltage is not within the range of ±5% of the
rated value or if the frequency is not within the range of ±2% of the rated value. Failure to observe
this may cause the pump to be overloaded, resulting in motor damage or a fire.
Even if the power fluctuations fall within the allowable ranges, the pump characteristics, motor
characteristics, and the temperature rise of the motor may differ from those at the rated voltage
and frequency.
(11) Precautions for using the inverter drive
• Ensure that the operation current value does not exceed 90% of the rated value.
• Ensure that the minimum frequency is set to 20 Hz.
(Contact us for operation at 20 Hz or below.)
• If the motor is powered at a different voltage, it cannot be inverter-driven. (If it is necessary to
use the motor with an inverter, contact Teral Inc.)
• An inverter-driven motor generates a magnetic sound which may sound more annoying than
those generated by the drives using unconverted commercial power.
• Although this magnetic sound does not cause an adverse effect on the quality of the motor,
some inverters allow the user to adjust the tone by changing the carrier frequency. However,
changing the frequency may reduce the allowable output of the inverter. Pay particular
attention when selecting the inverter.
• If the pump and motor produce resonance during normal operation, do not run them in the
range of the rotation speed.
Caution
Do not run the pump at a frequency exceeding 60 Hz. Failure to observe
this may overload the motor, causing it to burn out.
