Installing A Magnetic Contactor At The Power Supply Side; Connecting An Ac Or Dc Reactor - YASKAWA L1000V Technical Manual

8.4 Installing Peripheral Devices
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 from the Power Supply
Shut off the drive with a 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 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. Install a 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. Applications using a braking option should wire a thermal relay so that the output contactor opens when the
thermal relay trips. Inadequate braking circuit protection could result in death or serious injury by fire from overheating resistors.
WARNING! Fire Hazard. Confirm an actual motor overload condition is not present prior to increasing the thermal oL trip detection
setting. Check local electrical codes before making adjustments to motor thermal overload settings. Failure to comply can result in
death or serious injury by fire.
u Connecting an AC or DC Reactor
n
Reactor Placement
When connecting to a power supply transformer with greater than 600 kVA capacity, or when switching a phase advance
capacitor, large peak current can flow through the input power supply circuit and damage converter components in the
drive.
As a preventive measure, install an AC or DC reactor to the input side of the drive. Installing an AC or DC reactor will
also help improve the power factor.
Install an AC or DC reactor if a DC drive or another type of thyristor converter is running from the same power system,
regardless of the power supply conditions shown in
Figure 8.3
210
Figure
4000
Power supply harmonics
reactor required
Power Supply
Capacity (kVA)
600
0
Figure 8.3 Installing a Reactor
YASKAWA EUROPE SIEP
8.3.
Reactor unnecessary
60
Drive Capacity (kVA)
YEG
400
YASKAWA AC Drive L1000V Technical Manual