GE Fuji Electric MICRO-SAVER AF-300, Руководство для стартапов

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9-2 9-3
Name of option Function and application
Main option
Braking resistors
(Standard model)
(DBRs)
A braking resistor converts regenerative energy derived from deceleration of the motor and converts
it to heat for dissipation. Use of a braking resistor results in improved deceleration performance of the
drive.
DC reactors
(DCRs)
A DCR is mainly used for power supply normalization, and for supplied power factor correction (for
reducing harmonic components).
1) For power supply normalization
– Use a DCR when the capacity of a power supply transformer exceeds 500 kVA and is 10 times
or more the rated drive capacity. In this case, the percentage-reactance of the power source
decreases, and harmonic components and their peak levels increase. These factors may damage
rectifiers or capacitors in the converter section of drive, or degrade the capacitor (which can
shorten the drive’s service life).
– Also use a DCR when there are thyristor-driven loads or when power factor correction capacitors
are being turned on/off.
– Use a DCR when the interphase unbalance ratio of the drive power source exceeds 2%.
2) For supplied power factor correction (harmonic component reduction)
Generally a capacitor is used to correct the power factor of the load. However it cannot be used in
a system that includes a drive. Using a DCR increases the reactance of the drive’s power source
so as to decrease harmonic components on the power source lines and correct the drive’s power
factor. Using a DCR corrects the input power factor to approximately 95%.
Note: As shipped, the drive has a jumper bar connected across the terminals P1 and P (+) on the
terminal block. Remove the jumper bar when connecting a DCR.
Output circuit filters
(OFLs)
Include an OFL in the drive power output circuit to:
1) Suppress voltage fluctuation at the motor input terminals
This protects the motor from insulation damage caused by the application of high voltage surge
currents in 460 V drives.
2) Suppress leakage current from the power output lines (due to harmonic components)
This reduces the leakage current when the motor is connected by long power feed lines. It is
recommended that the length of the power feed line be kept to less than 1200 feet (400 m).
3) Minimize emission and/or induction noise in the power feed lines
OFLs are effective in reducing noise from long power feed lines, such as those used in plants, etc.
Note: Use an ACR within the allowable carrier frequency range specified by function code F26. The filter
will overheat is any other ACR is used.
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