LINK Systems Omni II Automatic Setups Module - Manual (Page 41)

October 16, 2008 Manual Version 1.1
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make a preliminary stop slightly above the desired setpoint. The system
will then incrementally “pulse” the slide adjust motor to achieve the
desired slide setpoint position. The pulse distance value must be set by
trial and error. A good starting point is .010" (.25mm). This value would
turn off the slide adjust motor .010" (.25mm) above any setpoint entered
before the pulse sequence would begin. The final stopping point will be
less than .010" (.25mm) above the setpoint value, and may end up below
the desired setpoint since electrical reaction times and mechanical inertia
will cause the slide to travel slightly further after the signal to stop is
given. The pulse distance selected is too large if the system has to pulse
more than a few times to get into final position after the preliminary stop,
and should be decreased. The pulse distance selected is too small if the
system overshoots the desired slide setpoint position, and should be
increased. No pulses will occur if this happens because the shut height
will already be below the intended setpoint.
Pulse Time
The system pulses the slide adjust motor starter when it gets close to
where it wants to go in order to do fine positioning, i.e., after making the
preliminary stop determined by the pulse distance. The pulse time must
be set by trial and error. A good starting value for this parameter is 30
msecS (milliseconds or 1/1000 of a second). If the system cannot pulse
into position during an auto adjust sequence, then this value should be
increased. A pulse time that produces an average change of about a half a
thousandth of an inch in shutheight for each pulse is desirable. Too long a
pulse time will result in overshooting the setpoint limit by an unacceptable
amount. Reduce the pulse time if significant overshoot occurs.
Resolver Turns
This parameter should be set to the number of turns for the dual resolver
being used for slide height position feedback. Normal setting for this unit
are 100 or 180 turns. See Table 4.1.
Table 4.1: Resolver Turns
Manufacturer Model # Turns
AMCI HTT-20-100 100
AMCI HTT-20-180 180
AMCI HTT-20-1000 100
AMCI HTT-20-1800 180
Section 4.2.2.2 Calibrating a Rotary Slide Adjust System
After setting the parameters in the previous section, the rotary slide system must be calibrated
before it can be used.