Delta Electronics VFD-EL manual Silicon Controlled Rectifier, power, reactor

		Appendix B Accessories
Application 2		Question
Silicon rectifier and AC motor drive are		Switching spikes will be generated when the
connected to the same power.		silicon rectifier switches on/off. These spikes
		may damage the mains circuit.
Correct wiring
		Silicon Controlled Rectifier
power	reactor
		DC

AC motor drive

reactor

motor

Application 3		Question
Used to improve the input power factor, to		When the mains power capacity is too large,
reduce harmonics and provide protection from		line impedance will be small and the charge
AC line disturbances. (surges, switching		current will be too high. This may damage AC
spikes, short interruptions, etc.). The AC line		motor drive due to higher rectifier
reactor should be installed when the power		temperature.
supply capacity is 500kVA or more and
exceeds 6 times the inverter capacity, or the
mains wiring distance ≤ 10m.
Correct wiring		small-capacity
large-capacity
		AC motor drive
power	reactor

motor

Revision August 2008, 2ELE, V1.02 B-11