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3.3.9.3
UNDERSTANDING HOW WAVEFORMS ARE GENERATED
Waveform are generated by the BOP by producing a series of discrete output levels (points) in a
prescribed pattern. In the case of sine, triangle and ramps, this produces an output that con-
forms to an approximation of the selected waveform type. The number of points available for a
waveform is limited to 3933 for all segments. Since there are a finite number of points, the lower
the frequency, the more points used, and the smoother the output waveform will appear. As the
frequency increases, fewer points are available for each cycle and the resulting waveform may
appear somewhat more jagged. Tables 3-9 and 3-10 list the number of points used for each fre-
quency range of sine, triangle and ramp waveforms and for square waveforms, respectively.
Levels use a maximum of 60 points.
This means that a waveform consisting of a single sinewave segment at 0.1 Hz will use all 3840
points to generate each cycle, while a sinewave at 440 Hz will use 24 points for each cycle.
Note that a single segment between 0.01Hz and 1.8Hz uses all available points, so subsequent
segments will not be accepted. Four segments of 10Hz will be acceptable, while five segments
at 10 Hz will not be accepted. Reducing the segment by using the start and stop angle will also
reduce the number of points used.
Each time a segment is added, the waveform is validated. When a segment is added that
causes the point total to exceed 3933, three asterisks *** will appear to the left of the segment,
and the error message "LIST TOO SMALL" will be displayed briefly. This can be corrected by
either reducing the number of segments, or increasing the frequency of the existing segments
until the point total is acceptable.
3.3.9.4
WAVEFORM SPECIFICATIONS
Refer to Table 1-2 for specifications applicable to waveforms created either locally, using the
BOP front panel (Local) or remotely from a host computer, using LIST commands (Remote). Dif-
ferences between local and remote operation are highlighted.
3-26
FIGURE 3-9.
SAVED WAVEFORMS MENU
BOP HIPWR 080709
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