Basic System Description; From Power Supply - Hitachi L200 Series Instruction Manual

Basic System Description

A motor control system will obviously include a motor and inverter, as well as a breaker
or fuses for safety. If you are connecting a motor to the inverter on a test bench just to get
started, that's all you may need for now. But a system can also have a variety of
additional components. Some can be for noise suppression, while others may enhance
the inverter's braking performance. The figure and table below show a system with all
the optional components you may need in your finished application.

From power supply

Breaker,
MCCB or
L1 L2 L3
+1
+
Inverter
GND
T1 T2 T3
Motor
Thermal
switch
NOTE: Note that some components are required for regulatory agency compliance (see
Chapter 5 and Appendix D).
Name
Breaker /
disconnect
GFI
Input-side
AC Reactor
Radio noise filter Electrical noise interference may occur on nearby
EMI filter (for
CE applications,
see Appendix D)
Radio noise filter
(use in non-CE
applications)
DC link choke
Radio noise filter Electrical noise interference may occur on nearby
Output-side
AC reactor
LCR filter
L200 Inverter
Function
A molded-case circuit breaker (MCCB), ground fault
interrupter (GFI), or a fused disconnect device. NOTE:
The installer must refer to the NEC and local codes to
ensure safety and compliance.
This is useful in suppressing harmonics induced on the
power supply lines and for improving the power factor.
WARNING: Some applications must use an input-
side AC reactor to prevent inverter damage. See
Warning on next page.
equipment such as a radio receiver. This magnetic
choke filter helps reduce radiated noise (can also be
used on output).
Reduces the conducted noise on the power supply
wiring between the inverter and the power distribution
system. Connect to the inverter primary (input side).
This capacitive filter reduces radiated noise from the
main power wires in the inverter input side.
Suppresses harmonics generated by the inverter.
However, it will not protect the input diode bridge
rectifier.
equipment such as a radio receiver. This magnetic
choke filter helps reduce radiated noise (can also be
used on input).
This reactor reduces the vibrations in the motor caused
by the inverter's switching waveforms, by smoothing
the waveform to approximate commercial power
quality. It is also useful to reduce harmonics when
wiring from the inverter to the motor is more than 10m
in length.
Sine wave shaping filter for output side.
2–7