Mitsubishi Electric FR-A720-0.4K Instruction Manual page 283

Operation selection at power failure
and instantaneous power failure
(6) Power failure deceleration signal (Y46 signal)
⋅ After deceleration at an instantaneous power failure, inverter cannot start even if the start command is given. In this
case, check the power failure deceleration signal (Y46 signal). (at occurrence of input phase failure protection
(E.ILF), etc.)
⋅ The Y46 signal is ON during deceleration at an instantaneous power failure or during a stop after deceleration at an
instantaneous power failure.
⋅ For the Y46 signal, set "46 (positive logic)" or "146 (negative logic)" in any of Pr. 190 to Pr. 196 (output terminal
function selection) to assign the function.
CAUTION
⋅ When Pr. 30 Regenerative function selection = "2" (FR-HC, MT-HC, FR-CV is used), the power failure deceleration function is
invalid.
⋅ When the (output frequency - Pr. 262) at undervoltage or power failure occurrence is negative, the calculation result is regarded
as 0Hz. (DC injection brake operation is performed without deceleration).
⋅ During a stop or error, the power failure stop selection is not performed.
⋅ Y46 signal turns ON when undervoltage occurs even when the motor is not decelerating at an instantaneous power failure.
For this reason, Y46 signal outputs instantly at powering OFF, which is not a fault.
⋅ When power failure deceleration stop function is selected, undervoltage protection (E.UVT), instantaneous power failure
protection (E.IPF), and input phase loss protection (E.ILF) do not function.
⋅ Changing the terminal assignment using Pr. 190 to Pr. 196 (output terminal function selection) may affect the other functions. Set
parameters after confirming the function of each terminal.
If power-failure deceleration stop function is set, some loads may cause the inverter to trip and the motor to
coast. The motor will coast if enough regenerative energy is given from the motor.
♦ Parameters referred to ♦
Pr. 12 DC injection brake operation voltage
Pr. 20 Acceleration/deceleration reference frequency, Pr. 21 Acceleration/deceleration time increments
Pr. 30 Regenerative function selection
Pr. 57 Restart coasting time
Pr. 190 to Pr. 196 (output terminal function selection)
Pr. 872 Input phase loss protection selection
272
CAUTION
Refer to page 203
Refer to page 207
Refer to page 266
Refer to page 239
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Refer to page 172