1 Product Information
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1.5.2 Peripheral Electrical Devices
Table 1-4
Description of peripheral electrical devices of the CP700 AC system
Part Name
Mounting Location
Function Description
Circuit breaker
Between power
supply and AC drive
input side
Short circuit breaker: cuts off power supply when
overcurrent occurs on downstream devices, so as to
prevent accidents.
Leakage breaker: provides protection against
potential high-frequency leakage current during AC
drive running to prevent electric shock and even a
fire. Choose proper leakage breaker according to the
field situation.
Fuse
Between power
supply and AC drive
input side
Provides protection in case of short circuit and
protect downstream semiconductor components.
(Electromagnetism)
Contactor
Between the breaker
and AC drive input
side
Used for applying or cutting off power supply of the
AC drive. Do not start and stop the AC drive frequently
by switching the contactor on and off (at least 1-hour
interval) nor use it to directly start the AC drive.
Input reactor
AC drive input side
Used for improving the power factor of power input
side.
Eliminates higher harmonics of the input side
effectively and prevents other devices from being
damaged due to distortion of voltage waveform.
Eliminates input current unbalance caused by inter-
phase unbalance.
EMC filter
AC drive input side
Reduces external conduction and radiation
interference of the AC drive.
Decreases conduction interference flowing from
power supply to the AC drive and improves the anti-
interference capacity of the AC drive.
Output reactor
Between the AC drive
output side and
motor (close to the
AC drive)
The output side of an AC drive usually has much
higher harmonics. When a motor is far away from the
AC drive, much distributed capacitance exists in the
circuit. Certain harmonics may cause resonance in
the circuit, which will:
1) Degrade motor insulation performance and
damage motor in the long run.
2) Generate large leakage current and cause frequent
AC drive protection trips.
If the distance between an AC drive and a motor is
greater than 100 m, it is recommended that an AC
output reactor be installed.
dv/dt reactor
AC drive output side
(close to the AC drive)
The optional dv/dt drive ensures motor insulation
and reduces bearing current.
Output magnetic
loop
AC drive output side
(close to the AC drive) Reduces bearing current.
