Fuji Electric FRENIC-MEGA, Instruction Manual

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The table below shows the conditions for zero speed control to be enabled or disabled.
Speed command Run command Data for d24 Operation
At startup
Below the starting and
stop frequencies
OFF ― Stop (Gate OFF)
ON
0 Stop (Gate OFF)
1 Zero speed control
At stop Below the stop frequency
ON ― Zero speed control
OFF ― Stop (Gate OFF)
„ Stop Frequency (Detection mode) (F38) (Under vector control with speed sensor)
F38 specifies whether to use the detected speed or reference one as a decision criterion to shut down the inverter output.
Usually the inverter uses the detected speed. However, if the inverter undergoes a load exceeding its capability, e.g., an
external excessive load, it cannot stop because the motor cannot stop so that the detected speed may not reach the stop
frequency level. When such a situation could arise, select the reference speed that can reach the stop frequency level even if
the detected speed does not, in order to stop the inverter without fail for general fail-safe operation.
- Data setting range: 0 (Detected speed)
1 (Reference speed)