Omron SYSDRIVE 3G3RV, User Manual

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If the Ground Fault Interrupter Operates When the Inverter Is Run
The
Inverter performs internal switching, so there is a certain amount of leakage current. This may cause the
ground
fault interrupter to operate and cut off the power supply. Change to a ground fault interrupter with a
high
leakage detection level (i.e., a sensitivity current of 200 mA or greater per Unit, with an operating time of
0.1
s or more), or one that incorporates high frequency countermeasures (i.e., one designed for use with Invert-
ers).
It will also help to some extent to change the Inverter's Carrier Frequency Selection (C6-02) to lower the
carrier
frequency. In addition, remember that the leakage current increases as the cable is lengthened.
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If There Is Mechanical Oscillation
Use
the following information when there is mechanical oscillation.
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The machinery is making unusual sounds.
The
following causes are possible.
There may be resonance between the mechanical system's characteristic frequency and the
carrier frequency.
If
the motor is running with no problems and the machinery is oscillating with a high-pitched whine, it may
indicate
that this is occurring. To prevent this type of resonance, adjust the carrier frequency with parameters
C6-02
to C6-05.
There may be resonance between a machine's characteristic frequency and the output fre-
quency of the Inverter.
To
prevent this from occurring, either use the jump frequency functions in parameters d3-01 to d3-04 or install
rubber
padding on the motor base to reduce oscillation.
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The motor vibrates strongly and won't operate normally.
This
may be caused by open phases in the motor output. Failure in one or two of the phases in a three-phase
motor
output will cause extremely strong vibration and prevent the motor from operating. Check for a faulty
motor
power line or disconnection. The same condition will also occur if the Inverter's output transistor is
open
and damaged. Check the balance of the Inverter output voltage.
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Oscillation and hunting are occurring with open-loop vector control.
The
gain adjustment may be insufficient. Reset the gain to a more effective level by adjusting parameters C4-
02
(torque compensation time constant), C2-01 (S-curve Characteristic Time at Acceleration Start), and C3-02
(Slip
Compensation Primary Delay Time) in order. Lower the gain setting and raise the primary delay time
setting.
Vector
control will not perform if autotuning has not been performed. Perform autotuning separately for the
motor,
or set the motor constants through calculations. Alternatively, change the control method selection (A1-
02)
to V/f control (0 or 1).