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880 ⏐⏐⏐ POWER (ac)<br />

+<br />

E = 100 V ∠90°<br />

–<br />

I s<br />

+<br />

Load 1<br />

200 VAR (L)<br />

0 W<br />

Load 2<br />

FIG. 19.42<br />

Problem 3.<br />

Load 1<br />

FIG. 19.43<br />

Problem 4.<br />

3. For the system of Fig. 19.42:<br />

a. Find the total number of watts, volt-amperes reactive,<br />

and volt-amperes, and the power factor F p.<br />

b. Draw the power triangle.<br />

c. Find the current I s.<br />

600 VAR (C)<br />

100 W<br />

E = 200 V ∠0° Load 2<br />

–<br />

600 VAR (C)<br />

500 W<br />

+<br />

E = 50 V ∠60°<br />

–<br />

I s<br />

I s<br />

Load 1<br />

1200 VAR (L)<br />

600 W<br />

Load 2<br />

100 VAR (L)<br />

200 W<br />

FIG. 19.44<br />

Problem 5.<br />

Load 3<br />

Load 3<br />

0 VAR<br />

300 W<br />

4. For the system of Fig. 19.43:<br />

a. Find P T, Q T, and S T.<br />

b. Determine the power factor F p.<br />

c. Draw the power triangle.<br />

d. Find I s.<br />

Load 3<br />

200 VAR (C)<br />

0 W<br />

600 VAR (L)<br />

100 W<br />

5. For the system of Fig. 19.44:<br />

a. Find P T, Q T, and S T.<br />

b. Find the power factor F p.<br />

c. Draw the power triangle.<br />

d. Find I s.<br />

100 VAR (L)<br />

200 W<br />

Load 4<br />

200 VAR (C)<br />

100 W<br />

P q<br />

s

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