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User Switches C1 Submenu
95
S-CURVE ABORT
This parameter, S-CURVE ABORT (C1),
addresses how the HPV 900 Series 2’s S-
Curve Speed Reference Generator handles a
reduction
in the speed command before the S-
Curve Generator has reached its target speed.
Note: the default for the S-CURVE ABORT
(C1) parameter is disabled.
S-curve Function with S-CURVE ABORT =
disabled
With a normal S-curve function, a change in
the speed command is never allowed to violate
the defined acceleration or jerk rates. If a
reduction in the speed command is issued
before the S-Curve generator has reached its
target speed, then the jerk rate dictates what
speed is reached before the speed may be
reduced.
Figure 36 below shows this type of operation.
Note the jerk rates are very low to exaggerate
proportion of S in the curve to clearly show the
overshoot in speed so that the maximum jerk
rate is not violated. In this figure, a reduction in
the speed command occurs from a high-speed
command (which was not yet achieved on the
output of the S-Curve) to a low speed
command. Note that the speed reference (S-
Curve output) continued to increase after the
speed command was reduced. This increase
is speed was necessary to avoid violation of
the jerk rate setting.
S-curve Function with S-CURVE ABORT =
enabled
In Figure 37 below, the optional S-Curve abort
has been selected. In this case when the
speed command is reduced, the speed
reference immediately starts to reduce
violating the jerk limit (thus no jerk out phase),
which could be felt in the elevator.
For optional S-Curve abort to be active
requires that:
The speed command source must be
selected as Multi-step (SPD COMMAND
SRC=multi-step).
The S-curve Abort function must be
ENABLED (S-CURVE ABORT = enabled).
Figure 36: Normal S-curve Abort
Figure 37: Optional S-curve Abort
speed command
speed reference
speed reduction
speed command
speed reference
speed reduction