MITSUBISHI ELECTRIC FR-S520 - Manual (Page 26)

17
1
1
.5.5 Power-off and magnetic contactor (MC)
CAUTION
Do not use the inverter power supply side magnetic contactor to start or stop the
inverter.
As shown on the right,
always use the start signal
(ON or OFF across
terminals STF or STR-SD)
to make a start or stop.
(Refer to page 28)
Power
supply
NFB
F
OFF
ON
MC
MC
RA
R
1
>
S
T
U
V
W
Inverter
STF (STR)
SD
MC
To
motor
OFF
ON
RA
RA
MC
OFF
B
C
Inverter Start/Stop Circuit Example
(1) Inverter's primary side magnetic contactor (MC)
On the inverter's primary side, it is recommended to provide an MC for the following
purposes (Refer to page 13 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 an accident caused by an automatic restart made at power restoration
after an inverter stop due to 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 a long time, switching inverter power off
saves power slightly.
4) To separate the inverter from the power supply to ensure safety of
maintenance/inspection work.
As the inverter's primary MC is used for the above purposes, it is equivalent to the
standard duty and select the one of class JEM1038-AC3 for the inverter input side
current.