IMO Jaguar CUB, Инструкция по эксплуатации

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9-3
Name of option Function and application
Braking resistors
(Standard model)
(DBRs) A braking resistor converts regenerative energy generated from deceleration
of the motor and converts it to heat for consumption. Use of a braking
resistor results in improved deceleration performance of the inverter.
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 inverter capacity. In this
case, the percentage-reactance of the power source decreases, and
harmonic components and their peak levels increase. These factors
may break rectifiers or capacitors in the converter section of inverter,
or decrease the capacitance of the capacitor (which can shorten the
inverter’s service life).
- Also use a DCR when there are thyristor-driven loads or when
condensive capacitors are being turned on/off.
- Use a DCR when the interphase voltage unbalance ratio of the
inverter power source exceeds 2%.
67
(V) voltage average phase - 3
(V) voltage Min. (V) voltage Max.
= (%) unbalance voltage Interphase
u
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 an inverter. Using a
DCR increases the reactance of inverter’s power source so as to
decrease harmonic components on the power source lines and correct
the power factor of inverter. Using a DCR corrects the input power factor
to approximately 90 to 95%.
Note: At the time of shipping, a jumper bar is connected across the
terminals P1 and P (+) on the terminal block. Remove the jumper bar when
connecting a DCR.
Main opti
o
n
Output circuit filters
(OFLs) Include an OFL in the inverter power output circuit to:
1) Suppress the voltage fluctuation at the motor input terminals
This protects the motor from insulation damage caused by the application
of high voltage surge currents by the 400 V class of inverters.
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
cable lengths. It is recommended that the length of the motor cable be
kept to less than 400 m.
3) Minimize emission and/or induction noise generated from the motor
cable.
OFLs are effective in reducing noise from long power feed lines, such as
those used in plants, etc.
Note: Use an OFL within the allowable carrier frequency range specified by
function code F26. Otherwise, the filter will overheat.