Rockwell Automation GV3000/SE AC Gen. Purpose and Vector Drive Software Start-Up and Ref. Manual - Manual (Page 148)

4-62 GV3000/SE AC Drive Software Reference, Version 6.06
The avoided frequency range is:
(Avoidance freq. midpoint ‘n’ - freq. band ‘n’/2) < range < (avoidance freq. midpoint ‘n’ + freq. band ‘n’/2)
where n = 1, 2, or 3.
Note that when Forward/Reverse Configuration (P.027) is set to 1, setting this
parameter to r, Fr, or rF may still cause the motor to operate in the reverse direction.
H.011, H.013, and H.015 Avoidance Frequency Band 1, 2, and 3
This parameter
specifies the
avoidance frequency
band that will be
applied to each
avoidance frequency
midpoint selected in
H.010, H012, and
H.014.
Parameter Range: 0.2 to 10 Hz
Default Setting: 2.0
Parameter Type: Tunable
Refer also to parameters: H.009 Avoidance Frequency Enable
H.010, H.012, H.014 Avoidance Frequency Midpoint
1, 2, and 3
H.016 Sync Direction
When starting into a
rotating load is
required, this
parameter selects the
direction in which the
drive will search in
order to synchronize
to motor speed.
Parameter Range: OFF = Disable synchronization
F = Search starts in motor forward direction
r = Search starts in motor reverse direction
Fr = Search starts in motor forward then reverse
direction
rF = Search starts in motor reverse then forward
direction
Default Setting: OFF
Parameter Type: Configurable
Refer also to parameters: N/A
!
ATTENTION: When starting with search enabled, there will be a several
second delay, and the motor may drift in the forward and reverse direction,
before the motor begins operating in the desired direction even if reverse
has been disabled in P.027. Stay clear of rotating machinery. Failure to
observe this precaution could result in bodily injury.