Selec VFD Series

56
User Manual
Hopping action is required in cases where the VFD could drive the motor through a frequency that
matches the resonant frequency of the system that is being controlled. This matching could cause
the entire system to vibrate which could prove to be harmful in the long run. The hopping feature
allows the user to skip through such resonant frequency values. The below diagram will make this
operation clearer. Note that in case of an overlap between the 2 hopping frequency ranges, band 1
will get a higher priority.
Output frequency
Hopping frequency band 1
Hopping frequency band 2
Set frequency
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PC-12
FDT Level
Detection Value
Lower Limiting Frequency (P0-10)
– Upper Limiting Frequency (P0-09)
Default:
0.0 Hz
PC-13
FDT Level
Lagged Value
Lower Limiting Frequency (P0-10)
– FDT Level Detection Value (PC-12)
Default:
0.0 Hz
These 2 parameters indicate that a particular frequency has been achieved. The operation is
explained in the diagram below.
Output frequency
FDT lagged value
FDT level
Frequency level
detection FDT
Time
Time
ON
}