Yaskawa AC Drive-P1000 Industrial Fan - Manual (Page 388)

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 Reactor or DC Link Choke
AC reactors and DC link chokes suppress surges in current and improve the power factor on the input side of the drive.
Use an AC reactor, a DC link choke, or both 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 or DC link choke 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 8.19 Connecting an AC Reactor
n Connecting a DC Link Choke
A DC link choke can be installed to drive models 2A0004 to 2A0081, 4A0002 to 4A0044, and 5A0003 to 5A0032. When
installing a DC link choke, remove the jumper between terminals ⊕1 and ⊕2 (terminals are jumpered for shipment). The
jumper must be installed if not using a DC link choke. Refer to Figure 8.20 for an example of DC link choke wiring.
A
C
D
R/L1
B
S/L2
T/L3
1 + 2 +
A – Power supply
B – MCCB
C – Drive
D – DC link choke
Figure 8.20 Connecting a DC Link Choke
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.
8.5 Installing Peripheral Devices
388 YASKAWA SIEP YAIP1U 01B AC Drive - P1000 Technical Manual