Voltage drop is the reduction in voltage due to the flow of current through the impedance in conducting line. Excessive voltage drop will result in unsatisfactory operation of electrical equipment, and represents energy wasted in the wiring system.
1. Branch Circuits – maximum voltage drop of 3%. (The maximum total voltage drop for a combination of both branch circuit and feeder should not exceed 5%)
2. Feeders – maximum voltage drop of 3%. (The maximum total voltage drop for a combination of both branch circuit and feeder should not exceed 5%)
3. Services - maximum voltage drop of 5%.
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