51
Installation of a reactor
3
PRECAUTIONS FOR USE OF THE INVERTER
3.2 Installation of a reactor
When the inverter is connected near a large-capacity power transformer (100 0kVA or more) or when a power capacitor is to
be switched over, an excessive peak current may flow in the power input circui t, damaging the converter circuit. To prevent
this, always install the AC reactor (FR-HAL)
3.3 Power-OFF and magnetic contactor (MC)
(1) Inverter input side magnetic contactor (MC)
On the inverter input side, it is recommended to provide an MC for the following purposes.
(Refer to page 4 for selection.)
1)To release the inverter from the power supply when the fault occurs or when the drive is not functioning (e.g.
emergency stop operation).
2)
To prevent any accident due to an automatic restart at restoration of power after an inverter stop made by a power failure
3)To separate the inverter from the power supply to ensure safe maintenance and inspection work
The inverter's input side MC is used for the above purpose, select class JEM1038-AC3MC for the inverter input side
current when making an emergency stop during normal operation.
(2) Handling of the inverter output side magnetic contactor
Switch the magnetic contactor between the inverter and motor only when both the inverter and motor are at a stop.
When the magnetic contactor is turned ON while the inverter is operating, overcurrent protection of the inverter and
such will activate. When an MC is provided to switch to a commercial power supply, for example, it is recommended to
use bypass operation Pr. 135 to Pr. 139 (Refer to page 293).
REMARKS
The wiring length between the FR-HEL and inverter should be 5m maximum and minimized. U se the same wire size as that of the
power supply wire (R/L1, S/L2, T/L3). (Refer to page 21)
REMARKS
Since repeated inrush current at power ON will shorten the life of the converter circuit (switching life is 100 million times (about
500,000 times for FR-F720-01540 or more)), frequent starts/stops must be avoided . Turn ON/OFF the inverter start controlling
terminals (STF, STR) to run/stop the inverter.
• Inverter start/stop circuit example
As shown on the left, always use the start signal
(ON or OFF of STF (STR) signal) to make a start
or stop. (Refer to page 126)
*1 When the power supply is 400V class, install a step-
down transformer.
*2 Connect the power supply terminals R1/L11, S1/L21
of the control circuit to the primary side of the MC to
hold an alarm signal when the inverter's protective
circuit is activated. At this time, remove jumpers
across terminals R/L1 and R1/L11 and S/L2 and S1/
L21. (Refer to page 25 for removal of the jumper.)
MCCB MC Inverter
AC reactor
(FR-HAL)
Power
supply
R
S
TZ
Y
XU
V
W
P1
DC reactor (FR-HEL) *
R/L1
S/L2
T/L3
P/+
IM
5000
5300
4000
3000
2000
1000
110165 247 330 420 550kV
A
Capacities requiring
installation of
AC reactor
Inverter capacity
Power supply system
capacity
(kVA)
* When connecting the FR-HEL to the FR-F720-02330 (FR-F740-01160) or less, remove the jumper across terminals P/+ and P1.
For the FR-F720-03160 (FR-F740-01800) or more, a DC reactor is supplied. Always install the reactor.
Power
supply
MCCB
RA
U
V
A1
B1
C1
W
To the
motor
Inverter
MC
STF(STR)
R/L1
S/L2
T/L3
R1/L11
S1/L21
OFF ON
MC
Stop
Start
RA
MC
Operation preparation
Start/Stop
MC
RA SD
T
*1
*2