Mitsubishi Electric FR-D720S SC EC Instruction Manual page 287

Parameter
Power failure deceleration signal (Y46 signal)
The Y46 signal is on during deceleration at an instantaneous power failure or during a stop after
deceleration at an instantaneous power failure.
After a power failure stop, the inverter can not start even if power is restored the start command
is given. In this case, check the power failure deceleration signal (Y46 signal) (at occurrence of
input phase loss (E.ILF), etc.).
In case of a power failure, signal Y46 is connected through during the brake time or in standstill
after expiration of the brake time. For the Y46 signal, set "46" (forward operation) or "146" (re-
verse operation) to any of Pr. 190, Pr. 192 or Pr. 197 to assign the function.
NOTES During a stop or trip, the power failure stop selection is not performed.
Signal Y46 is switched on in case of undervoltage, even if the brake is not applied to the
motor during a temporary power failure. For this reason, Signal Y46 is permanently output
during the switch-on routine. This is NOT an error.
Changing the terminal assignment using Pr. 190, Pr. 192 and Pr. 197 may affect the other
functions. Please make setting after confirming the function of each terminal.
b
CAUTION:
If power-failure deceleration operation 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.
FR-D700 SC EC
Operation selection at power failure
6 - 137