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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.
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Connecting an AC Reactor
B
A
C
D
R/L1
U
V
W
X
Y
Z
S/L2
T/L3
A – Power supply
B – MCCB
C – AC reactor
D – Drive
Figure 8.3 Connecting an AC Reactor
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Connecting a DC Reactor
Ensure the jumper between ter1 and +2 (terminals are jumpered for shipment) is removed when connecting a DC
reactor. The jumper must be installed if no DC reactor is used.
Refer to Connecting a DC Reactor on page 279
for an
example of DC reactor wiring.
A
C
D
R/L1
+1
+2
B
S/L2
T/L3
A – Power supply
B – MCCB
C – Drive
D – DC reactor
Figure 8.4 Connecting a DC Reactor
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Connecting a Surge Protector
A surge protector suppresses surge voltage generated from switching an inductive load near the drive. Inductive loads
include magnetic contactors, relays, valves, solenoids and brakes. Always use a surge protector or diode when operating
with an inductive load.
Note:
Never connect a surge protector to the drive output.
u
Connecting a Noise Filter
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Input-Side Noise Filter
Drive outputs generate noise as a result of high-speed switching. This noise flows from inside the drive back toward the
power supply, possibly affecting other equipment. Installing a noise filter to the input side of the drive can reduce the
amount of noise flowing back into the power supply. This also prevents noise from entering the drive from the power
supply.
• Use a noise filter specifically designed for AC drives.
• Install the noise filter as close as possible to the drive.
8.4 Installing Peripheral Devices
SIEP C710606 20 OYMC AC Drive - V1000 User Manual
279
8
Peripheral Devices & Options
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