Installing A Magnetic Contactor At The Power Supply Side; Connecting An Ac Or Dc Reactor - YASKAWA AC Drive-A1000 Technical Manual

8.5 Installing Peripheral Devices
• Size of the AC drive
• AC drive carrier frequency
• Motor cable type and length
• EMI/RFI filter
If the GFCI trips spuriously, consider changing these items or use a GFCI with a higher trip level.
Note: Choose a GFCI designed specifically for an AC drive. The operation time should be at least 0.1 s with sensitivity amperage of at least 200 mA
per drive. The output waveform of the drive may cause an increase in leakage current. This may in turn cause the leakage breaker to malfunction.
Increase the sensitivity amperage or lower the carrier frequency to correct the problem.
u

Installing a Magnetic Contactor at the Power Supply Side

Install a magnetic contactor (MC) to the drive input for the purposes explained below.
n Disconnecting the Power Supply
Shut off the drive with an MC when a fault occurs in any external equipment such as braking resistors.
NOTICE: Do not connect electromagnetic switches or MCs to the output motor circuits without proper sequencing. Improper sequencing of
output motor circuits could result in damage to the drive.
NOTICE: Install an 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. Install an MC to the drive input side to prevent the drive from restarting automatically when power is restored after momentary power loss.
2. Set up a delay that prevents the MC from opening prematurely to continue operating the drive through a momentary power loss.
n 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.
u

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.
n Connecting an AC Reactor
A – Power supply
B – MCCB
368
C
A B
U
V
W
C – AC reactor
D – Drive
Figure 8.9 Connecting an AC Reactor
YASKAWA ELECTRIC SIEP C710616 31B YASKAWA AC Drive – A1000 Technical Manual
D
X R/L1
Y S/L2
Z T/L3