Electricity distribution

1.Distribution systems in general

In general, the distribution system is the electrical system between the substation fed by the transmission system and the consumer end. Here relatively lower voltage levels are used since closer proximity to livelihoods. It distributes power to a relatively lower sect and expanse of crowd. Good voltage regulation of a distribution network is probably the most important factor responsible for delivering good service to the consumers. For this purpose, design of feeders and distributors requires careful consideration.

Fun Fact:Distribution systems usually employ such equipment as transformers, circuit breakers, and protective devices. The original electrical distribution system developed by Thomas Edison(or N. Tesla :P) was an underground direct current (DC) system.

Feeders

A feeder is a conductor which connects the substation (or localized generating station) to the area where power is to be distributed. Generally, no tappings(adding new wiring to an existing branch circuit to provide electrical power for added loads such as receptacles or lighting) are taken from the feeder so that current in it remains the same throughout.

A feeder is designed from the point of view of its current carrying capacity while the voltage drop consideration is relatively unimportant. It is because voltage drop in a feeder can be compensated by means of voltage regulating equipment at the substation.

Distributor

A distributor is a conductor from which tappings are taken for supply to the consumers. The current through a distributor is not constant because tappings are taken at various places along its length.

A distributor is designed from the point of view of the voltage drop in it. It is because a distributor supplies power to the consumers and there is a statutory limit of voltage variations at the consumer’s terminals). The size and length of the distributor should be such that voltage at the consumer’s terminals is within the permissible limits.

Service mains

A service main is generally a small cable which connects the distributor to the consumers’ terminals.