Influence To Inverter At Instantaneous Power Failure - Mitsubishi Electric FATEC FR-A800 Manual

7
REVIEW OF INSTALLATION ENVIRONMENT
7.1.6

Influence to inverter at instantaneous power failure

When an instantaneous power failure occurs, the power supply voltage of the control circuit for the
inverter is shut off. To prevent malfunction of control due to this power failure, activate the
instantaneous power failure protection to stop the inverter output and keep the output stopped. The
protective operation differs depending on the instantaneous power failure time. The FR-A800 series
is used as an example here.
(1) Inverter operation depending on the instantaneous power failure time
(a) When the instantaneous power failure time
is within 15 ms
Since the protective function is not
activated, operation can continue normally.
Power
supply
Output
Fig. 7.6 Instantaneous power failure for 15 ms
7.1 Power supply of inverter (harmonics and instantaneous power failure)
96
Within 15 ms
f
N
Operation continues.
or less
(b) When the instantaneous power failure time is
over 15 ms and under 100 ms
The protective function is activated and the
inverter output is stopped. (The motor coasts
to a stop.)
Power
supply
t
f
f
N
N
t
Fault output/display
Fig. 7.7 Instantaneous power failure for more
than 15 ms and less than 100 ms
15 ms to 99 ms
15ms
Output shutoff
Motor coasts to a stop.
Held