Yaskawa Z1000 AC Drive HVAC - Manual (Page 245)

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.
u Connecting an AC Reactor
AC reactors suppress surges in current and improve the power factor on the input side of the drive.
Use an AC reactor in the following situations:
• 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 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
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 6.9 Connecting an AC Reactor
u Connecting a Surge Absorber
A surge absorber 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 absorber or diode when operating with an
inductive load.
WARNING! Fire Hazard. Due to surge absorber short circuit on drive output terminals U/T1, V/T2, and W/T3, do not connect surge absorbers
to the drive output power terminals. Failure to comply may result in serious injury or death by fire or flying debris.
u Connecting a Noise Filter
n Input-Side Noise Filter
Drive outputs generate noise as a result of high-speed switching. This noise flows from inside the drive back to 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.
6.5 Installing Peripheral Devices
YASKAWA ELECTRIC TOEP YAIZ1U 03A YASKAWA AC Drive – Z1000 User Manual 245
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Peripheral Devices & Options