TM 9-6115-604-34
NAVFAC P-8-633-34
1
No load
2
½ rated load
3
No load
4
½ rated load
5
No load
6
½ rated load
7
No load
8
½ rated load
9
¼ rated load
10
3/4 rated load
11
1/4 rated load
12
3/4 rated load
13
1/4 rated load
14
3/4 rated load
15
1/4 rated load
16
3/4 rated load
17
1/2 rated load
18
4/4 rated load
19
1/2 rated load
20
4/4 rated load
21
1/2 rated load
22
4/4 rated load
23
1/2 rated load
24
4/4 rated load
(d) Repeat steps (a) through (c), above, for 50 Hz operation.
d.
Results.
(1)
Prepare a chart for each load change giving the momentary overshoot or undershoot, and the recovery
time. For each constant load, give the maximum voltage variation.
(2)
Referring to Figure 12-9, begin by determining the observed (B), and steady-state (D) voltage bandwidths.
(a)
Numerically mark the stabilizations occurring after each load change, starting with the stabilization
obtained before the first load change.
(b)
Determine the observed voltage band with (B) by marking the maximum trace excursion and
minimum trace excursion in the stabilized portion. Draw two lines parallel to the axis of the chart
movement, one each passing through these maximum and minimum trace excursions, respectively.
(c)
Draw a line (C) parallel to and equidistant from the edges of the observed voltage bandwidth,
determined in step b, above.
(d)
Using the rated voltage of the generator, and the given requirements of Table 12-3, calculate the
steady-state voltage bandwidth (D). Draw this steady-state voltage bandwidth as two parallel lines,
parallel to, and equidistant from, the median (C) at the observed voltage bandwidth.
12-31
