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A separately excited DC generator has a no-load voltage of 127 V, Ra = 0.02 Ω and Rsh = 15Ω Find the armature current when the generator terminal voltage is 120 V on load.

A separately excited DC generator has a no-load voltage of 127 V, Ra = 0.02 Ω and Rsh = 15Ω Find the armature current when the generator terminal voltage is 120 V on load. Correct Answer 350 A

Concept:

Separately excited DC generator circuit is given as,

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Eg = Vt + IaRa

Where, Eg = no-load armature voltage

Vt = terminal voltage under loaded condition

Ia = armature current, and also load current

Ra = armature resistance

Rsh = shunt resistance

Calculation:

Given:

E­g = 127 V, Vt = 120 V, Ra = 0.02 Ω

Eg = Vt + IaRa

127 = 120 + Ia × 0.02

0.02Ia = 7

Ia = 350 A

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