Fuji Electric FRENIC-VG Series, Руководство пользователя

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Maintenance and inspection, and parts replacement
• Before proceeding to the maintenance/inspection jobs, turn OFF the power and wait at least five minutes for
inverters with a capacity of 22 kW or below, or at least ten minutes for inverters with a capacity of 30 kW or
above . Make sure that the LED monitor and charging lamp are turned OFF. Further, make sure, using a multimeter or a
similar instrument, that the DC link bus voltage between the terminals P(+) and N(-) has dropped to the safe level (+25
VDC or below).
Otherwise, an electric shock could occur.
• Maintenance, inspection, and parts replacement should be made only by qualified persons.
• Take off the watch, rings and other metallic objects before starting work.
• Use insulated tools.
Otherwise, an electric shock or injuries could occur.
• Never modify the inverter.
Doing so could cause an electric shock or injuries.
Disposal
• Treat the inverter as an industrial waste when disposing of it.
Otherwise injuries could occur.
Speed control mode
• If the control parameters of the automatic speed regulator (ASR) are not appropriately configured under speed control,
even turning the run command OFF may not decelerate the motor due to hunting caused by high gain setting.
Accordingly, the inverter may not reach the stop conditions so that it may continue running.
Even if the inverter starts deceleration, the detected speed deviates from the zero speed area before the zero speed
control duration (F39) elapses due to hunting caused by high response in low speed operation. Accordingly, the inverter
will not reach the stop conditions so that it enters the deceleration mode again and continues running.
If any of the above problems occurs, adjust the ASR control parameters to appropriate values and use the speed
mismatch alarm function in order to alarm-trip the inverter, switch the control parameters by speed, or judge the
detection of a stop speed by commanded values when the actual speed deviates from the commanded one.
An accident or injuries could occur.
Torque control mode
• When the motor is rotated by load-side torque exceeding the torque command under torque control, turning the run
command OFF may not bring the stop conditions so that the inverter may continue running.
To shut down the inverter output, switch from torque control to speed control and apply a decelerate-to-stop or
coast-to-stop command.
An accident or injuries could occur.
GENERAL PRECAUTIONS
Drawings in this manual may be illustrated without covers or safety shields for explanation of detail parts. Restore the
covers and shields in the original state and observe the description in the manual before starting operation.