(A) Application parameters
Power failed signal (Y67 signal)
● Y67 signal turns ON when the output is shut off due to detection of power failure (power supply
fault) or undervoltage, or the power failure time deceleration-to-stop function is activated.
● To use the Y67 signal, assign the function by setting "67 (positive logic)" or "167 (negative logic)"
in any of Pr. 190 to Pr. 196 (output terminal function selection).
When "2" is set to Pr. 30 "Regenerative function selection" (for instance, when FR-HC2, FR-CV is
used), the deceleration-to-stop function is invalid at a power failure.
If the "output frequency – Pr. 262" at undervoltage or at power failure is a negative value, it is
regarded as 0 Hz. (DC injection brake operation is performed without deceleration.)
The power failure time deceleration stop function is disabled during a stop or when the breaker is
The Y46 signal turns ON if an undervoltage occurs even if a deceleration at a power failure has not
occurred. For this reason, the Y46 signal is sometimes output instantaneously when the power
supply is turned OFF. This is not a fault.
When the power failure time deceleration-to-stop function is selected, undervoltage protection
(E.UVT), instantaneous power failure protection (E.IPF) and input phase loss protection (E.ILF) are
When the load is high during PM motor control, an undervoltage sometimes causes the inverter to
coast to a stop.
Changing the terminal assignment using Pr. 178 to Pr. 189 (input terminal function selection) or
Pr. 190 to Pr. 196 (output terminal function selection) may affect the other functions. Set parame-
ters after confirming the function of each terminal.
● Even if the power failure time deceleration stop function is set, some loads might cause the
inverter to trip and the motor to coast.
● The motor will coast if sufficient regenerative power is not obtained from the motor.
Parameters referred to
Pr. 190 to Pr. 196
5 - 438
DC injection brake operation voltage
Acceleration/deceleration reference frequency
Acceleration/deceleration time increments
Regenerative function selection
Restart coasting time
(output terminal function selection)
Input phase loss protection selection
page 5-415, page 5-423