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If OV is Detected When a Fan is Started or Fan Stalls
Generation of OV (Over Voltage) and stalling can occur if a fan is turning when it is started. The DC injection
braking is insufficient when starting.
This can be prevented by slowing fan rotation by DC injection braking before starting the fan. Increase the
parameter b2-03 (DC injection braking time (initial excitation) at start) setting.
If Output Frequency Does Not Rise to Frequency Reference
The frequency reference is within the jump frequency range.
When the jump frequency function is used, the output frequency does not change within the jump frequency
range. Check to be sure that the Jump Frequency (parameters d3-01 to d3-03) and Jump Frequency Width
(parameter d3-04) settings are suitable.
The frequency reference upper limit has been reached.
The output frequency upper limit is determined by the following formula:
Maximum Output Frequency (E1-04)
×
Frequency Reference Upper Limit (d2-01) / 100
Check to be sure that the parameter E1-04 and d2-01 settings are suitable.