What does s/c and 115 ohms mean?

One disadvantage of low power factor is O Reduces conductor sizes Reduces electricity bills O Increases the voltage drop in the system O Reduces copper losses

A 107 hp, 257 V de shunt motor has the magnetization curve in the graph. The armature circuit resistance, including brushes, is .032 ohm. no load rotational losses are 2087 w and the stray loss is 1% of the output The field rheostat is adjusted for a no-load speed of 1107 pm a. What would be the field current at no load when speed is 1100 rpm b. Determine Speed and output in horsepower corresponding to an armature current of 400A c. Now a cumulative series turns 2 (N) per pole is to be added with R negligible and 1000 turns in Shunt field find speed corresponding to an armature current of 400A

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