Search FAQs

Altivar Process drive ATV600 Jump frequency function detailed explanation

Jump frequency means that motor cannot be operated at steady speed at the speed range around the jump frequency. Altivar Process ATV6xx allows to configure 3 jump frequencies JPF, JF2, JF3. The range of speed around jump frequency is specified by hysteresis JFH
So the speed range JPF-JFH...JPH+JFH (and likewise for second JF2+-JFH and third jump frequency JF3+-JFH if configured) is only for transient purpose. Motor can pass thru this speed (with respect standard ACC, DEC ramps), but will not be operated continuously at this speed range. If speed reference is within "jump" range JPF -JFH . . . JPF +-FH, the motor speed will achieve steady speed, either JPF -JFH or JPF +JFH depending on what motor speed was (below or above jump range) before speed reference entered "jump range".

Note that in case of sudden change of speed reference that is out of jump range, e.g. from 0 to 60Hz or from 60Hz to 0Hz, the jump frequency will not play the role at all, because speed reference will always be outside the jump range, so motor will fluently cross via this range without noticing any difference.

But if you limit the speed that collides with jump range, the motor will not go to the other side of jump range. For example HSP=50Hz, JPF=47Hz and JFH=5Hz, the motor speed will never exceeds 42Hz, because speed reference will never exceeds 47+5Hz