Hitachi hitachi series inverter user manual Basic System Description, Gfi, Inverter +

Basic System Description

A motor control system will obviously include a motor and inverter, as well as a circuit 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 might need in your finished application.

Breaker,

MCCB or

GFI

L1	L2	L3
		+1
Inverter +
		GND
T1	T2	T3

From power supply

Breaker /	A molded-case circuit breaker (MCCB), ground fault
disconnect	interrupter (GFI), or a fused disconnect device. NOTE: The
	installer must refer to the NEC and local codes to ensure
	safety and compliance.
Input-side	This is useful in suppressing harmonics induced on the
AC Reactor	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.
Radio noise filter	Electrical noise interference may occur on nearby
	equipment such as a radio receiver. This magnetic choke
	filter helps reduce radiated noise (can also be used on
	output).
EMC filter (for	Reduces the conducted noise on the power supply wiring
CE applications,	between the inverter and the power distribution system.
see Appendix D)	Connect to the inverter primary (input) side.
Radio noise filter	This capacitive filter reduces radiated noise from the main
(use in non-CE	power wires in the inverter input side.
applications)
DC link choke	Suppress harmonics generated by the inverter. However, it
	will not protect the input diode bridge rectifier.
Radio noise filter	Electrical noise interference may occur on nearby
	equipment such as a radio receiver. This magnetic choke
	filter helps reduce radiated noise (can also be used on
	input).
Output-side	This reactor reduces the vibration in the motor caused by
AC Reactor	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.
LCR filter	Sine wave shaping filter for output side.

M

Thermal switch

9