Installing A Magnetic Contactor - YASKAWA A1000 Technical Manual

 Installing a Magnetic Contactor
Install a magnetic contactor to the drive input for the purposes explained below.

Disconnecting the Power Supply
The drive should be shut off with a magnetic contactor (MC) when a fault occurs in any external equipment such as
braking resistors.
NOTICE: Do not connect electromagnetic switches or magnetic contactors to the output motor circuits without proper sequencing.
Improper sequencing of output motor circuits could result in damage to the drive.
NOTICE: Install a MC on the input side of the drive when the drive should not automatically restart after power loss. To get the full
performance life out of the electrolytic capacitors and circuit relays, refrain from switching the drive power supply off and on more than
once every 30 minutes. Frequent use can damage the drive. Use the drive to stop and start the motor.
NOTICE: Use a magnetic contactor (MC) to ensure that power to the drive can be completely shut off when necessary. The MC should
be wired so that it opens when a fault output terminal is triggered.
Note: 1. To keep the drive from restarting automatically when power is restored after momentary power loss, install a magnetic contactor to
the drive input.
2. To have the drive continue operating through momentary power loss, set up a delay for the magnetic contactor so that it does not open
prematurely.

Protecting the Braking Resistor or Braking Resistor Unit
Use an MC on the input side of the drive to protect a braking resistor or braking resistor unit from overheat or fire.
WARNING! Fire Hazard. When using a braking unit, use a thermal relay on the braking resistors and configure a fault contact output
for the braking resistor unit to disconnect drive main power via an input contactor. Inadequate braking circuit protection could result in
death or serious injury by fire from overheating resistors.
 Connecting an AC or DC Reactor
AC and DC reactors suppress surges in current and improve the power factor on the input side of the drive.
Use a DC reactor or AC reactor or both:
• To suppress harmonic current or improve the power factor of the power supply.
• When using a phase advancing capacitor switch.
• With a large capacity power supply transformer (over 600 kVA).
Note: Use an AC or DC reactor when also connecting a thyristor converter (such as a DC drive) to the same power supply system,
regardless of the conditions of the power supply.

Connecting an AC Reactor
Note: Set C6-02 to 1 (Carrier Frequency Selection to 2.0 kHz) when connecting an AC reactor to the output side (secondary side) of the
drive.
Figure 8.22
YASKAWA ELECTRIC SIEP C710616 27G YASKAWA AC Drive A1000 Technical Manual
C
A B
U
V
W
A – Power supply
B – MCCB
Figure 8.24 Connecting an AC Reactor
8.5 Installing Peripheral Devices
D
X R/L1
Y S/L2
Z T/L3
C – AC reactor
D – Drive
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