Mitsubishi Electric FR-A820-00046 (0.4K) Instruction Manual page 613

 Power failure stop function (Pr.261 = "1, 11, or 21")
• Even if power is restored during deceleration triggered by a power failure, deceleration stop is continued after which the
inverter stays stopped. To restart operation, turn the start signal OFF then ON again.
Pr.261 = "1"
Power
supply
STF
Turn OFF STF once to make acceleration again
Y46
NOTE
• If the automatic restart after instantaneous power failure is selected (Pr.57 Restart coasting time ≠ "9999") while the power
failure time deceleration stop function is set enabled (Pr.261 = "1, 11, or 21"), the power failure time deceleration stop function
is disabled.
• When the power failure time deceleration stop function is enabled (Pr.261 = "1, 11 or 21"), the inverter does not start even if
the power is turned ON or inverter reset is performed with the start signal (STF/STR) ON. Turn OFF the start signal once and
then ON again to make a start.
Power supply
 Continuous operation function at instantaneous power failure (Pr.261 =
"2, 12, or 22")
• The motor re-accelerates to the set frequency when the power restores during the deceleration to stop.
• Combining with the automatic restart after instantaneous power failure function enables a power failure deceleration stop
and re-acceleration at a power restoration.
If the power is restored after stoppage by a power failure, a restart operation is performed when automatic restart after
instantaneous power failure (Pr.57 ≠ "9999") is selected.
Pr.261 = 2
Power
supply
Output
frequency
During deceleration
at occurrence of
power failure
Y46
*1 Acceleration time depends on Pr.7 (Pr.44)
 Undervoltage avoidance function (Pr.261 = "11 or 12", Pr.294)
• When "11 or 12" is set to Pr.261, the deceleration time is adjusted (shortened) to prevent an undervoltage from occurring
during deceleration at occurrence of power failure.
• Adjust the downward frequency slope and the response level using Pr.294 UV avoidance voltage gain. Setting a large
value improves the response to the bus voltage.
612
5. PARAMETERS
5.14 (A) Application parameters
During deceleration at
occurrence of power failure
During stop at
occurrence of
power failure
ON
Not started as inverter
is stopped due to power
failure
STF
OFF
Y46 ON
When power is restored during
deceleration at occurrence of
power failure
IPF
Reacceleration ∗1
Time
Time
Output
frequency
Time
ON
Pr.261 = 2, Pr.57
During power failure
Power
supply
Output
frequency
During deceleration
at occurrence of
power failure
Y46
When used with automatic restart
9999
after instantaneous power failure
Automatic restart
after instantaneous
power failure
Reset time + Pr.57
Time