Power-Off And Magnetic Contactor (Mc); Installation Of A Reactor - Mitsubishi Electric F700 Instruction Manual

2.3.2

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 3 for selection.))
1) To release the inverter from the power supply when the inverter's protective function is activated 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 rest the inverter for a long time. The control power supply for inverter is always running and consumes a little
power. When stopping the inverter for an extended period of time, powering off the inverter will save power slightly.
4) 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.
REMARKS
The MC may be switched on/off to start/stop the inverter. However, since repeated inrush currents at power on will shorten the
life of the converter circuit (switching life is about 1000,000 times), frequent starts and stops must be avoided. Turn on/off the
inverter start controlling terminals (STF, STR) to run/stop the inverter.
Power
supply
Operation preparation
OFF ON
MC
Start/Stop
MC
Operation
Stop
RA
(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 commercial power supply-inverter switchover operation Pr. 135 to Pr. 139.
2.3.3

Installation of a reactor

When the inverter is connected near a large-capacity power transformer (1000kVA or more and wiring length 10m
max.) or when a power capacitor is to be switched over, an excessive peak current may flow in the power input circuit,
damaging the inverter. To prevent this, always install the optional DC reactor (FR-HEL) or AC reactor (FR-HAL)
MCCB MC
Power
supply
* When connecting the FR-HEL to the 01160 or less, remove the jumper across terminals P-P1.
.
REMARKS
The wiring length between the FR-HEL and inverter should be 5m maximum and minimized. Use the same wire size as that of
the power supply wire (R/L1, S/L2, T/L3). (Refer to page 7)
MCCB
MC
R/L1
S/L2
T/L3
R1/L11
*2
S1/L21
T
*1
Inverter
MC
RA
STF(STR)
PC
RA
AC reactor
Inverter
(FR-HAL)
X
R
R/L1 U
S Y
S/L2 V
T Z
W
T/L3
P/+ P1
DC reactor
(FR-HEL) *
• Inverter start/stop circuit example
U
As shown on the right, always use the start
To the
signal (ON or OFF across terminals STF or
V
motor
STR-PC) to make a start or stop. (Refer to page
W
89)
*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
C1
the MC to hold an alarm signal when the
inverter's protective circuit is activated. At this
B1
time, remove jumpers across terminals R/L1-
A1
R1/L11 and S/L2-S1/L21. (Refer to page 14 for
removal of the jumper.)
1500
Installation
range of reactor
IM
1000
0
Others
Wiring
10
length (m)
31
2