Ac / Dc Reactor - Delta IED-S Series User Manual

Chapter 6 Optional Accessories | IED-S

6-4 AC / DC Reactor

AC Input Reactor
Installing an AC reactor on the input side of an AC motor drive can increase line impedance, improve
the power factor, reduce input current, increase system capacity, and reduce interference generated from
the motor drive. It also reduces momentary voltage surges or abnormal current spikes. For example,
when the main power capacity is higher than 500 kVA, or when using a switching capacitor bank,
momentary peak voltage and current spikes may damage the AC motor drive's internal circuit. An AC
reactor on the input side of the AC motor drive protects it by suppressing surges.
Installation
Install an AC input reactor in series between the main power and the three input phases R S T, as shown
in the figure below:
DC Reactor
A DC reactor can also increase line impedance, improve the power factor, reduce input current,
increase system power, and reduce interference generated from the motor drive. A DC reactor stabilizes
the DC bus voltage. Compared with an AC input reactor, a DC reactor is in smaller size, lower price, and
lower voltage drop (lower power dissipation).
Installation
Install a DC reactor between terminals +1(DC+) and +2/B1(DC+). Remove the DC reactor jumper, as
shown in the figure below, before installing a DC reactor.
Connecting an AC Input Reactor
6-8