Mitsubishi Electric FR-F720P-0.75K to 110K Instruction Manual page 181

Operation selection at power failure
and instantaneous power failure
(3) Power failure stop function (Pr. 261 = "1, 21")
⋅ If power is restored during power failure deceleration, deceleration to a stop is continued and the inverter remains
stopped. To restart, turn OFF the start signal once, then turn it ON again.
⋅ With the Pr.261 = "21" setting, the deceleration time is automatically adjusted to keep (DC bus) voltage constant in
the converter when the motor decelerates to a stop at a power failure. (The Pr.262 to Pr.266 settings become
invalid.)
Pr.261 = 1
Power
supply
STF
Y46
Turn OFF STF once to make acceleration again
REMARKS
⋅
When automatic restart after instantaneous power failure is selected (Pr. 57
restart after instantaneous power failure operation is performed.
⋅
When the power failure deceleration stop function is active (Pr.261
"1, 21"), the inverter will not start even if the power is turned ON with
the start signal (STF/STR) ON. After switching ON the power supply,
turn OFF the start signal once and then ON again to make a start.
(4) Operation continuation at instantaneous power failure function (Pr. 261 = "2, 22")
⋅ When power is restored during deceleration after an instantaneous power failure, acceleration is made again up to
the set frequency.
⋅ When this function is used in combination with the automatic restart after instantaneous power failure operation,
deceleration is available at a power failure and acceleration is available again after power restoration. When power
is restored after a stop by deceleration at an instantaneous power failure, automatic restart operation is performed
if automatic restart after instantaneous power failure has been selected (Pr. 57 ≠ "9999")
⋅ With the Pr.261="22" setting, the deceleration time is automatically adjusted to keep (DC bus) voltage constant in
the converter when the motor decelerates to a stop at a power failure. The motor re-accelerates to the set
frequency if the power is restored during the deceleration to stop.
⋅ Setting Pr. 261 = "22" disables the settings of Pr. 262 to Pr. 266.
.
When power is restored during
Pr. 261 = 2, 22
deceleration at occurrence of
power failure
Power
supply
Output
frequency
During deceleration
at occurrence of
power failure
Y46
* Acceleration time depends on Pr. 7 (Pr. 44 ).
170
During deceleration at
occurrence of power failure
During stop at
occurrence of
power failure
Time
IPF
Reacceleration*
Time
Pr.261 = 21
Power
supply
STF
Y46
Turn OFF STF once to make acceleration again
≠
"9999"), deceleration to stop function is invalid and the
≠
Power supply
STF
Y46
Pr.261 = 2, 22, Pr.57
9999
During power failure
Power
supply
Output
frequency
During deceleration
at occurrence of
power failure
Y46
During deceleration at
occurrence of power failure
Deceleration time: automatically adjusted
During stop at
occurrence of
power failure
Time
ON
Not started as inverter Output
is stopped due to power frequency
failure
OFF
ON
ON
When used with automatic restart
after instantaneous power failure
Automatic restart
after instantaneous
power failure
Time
Reset time + Pr.57
Time