Overhead(O/H) Power Distribution

Power Distribution is the last part of the delivery of electrical energy to consumers. It is normally done in low voltage, for example 400V/230V denoting 3phase/1phase. In some cases this can be, medium voltages like 11kV/ 33kV.

This can be done by conductors, either drawn OverHead (O/H conductors) or buried underground (Insulated cables). Each have their own advantages and drawbacks. for e.g.: In densely populated areas - undergroung cables are preferred. At the same time, cables are costly than O/H conductors. In addition, faultfinding is a cumbersome process in underground cables. On the other hand, O/H cables are mostly vulnerable to lightning surges, bad weather conditions etc.


Here we will mostly consider about O/H power distribution and its main components:

It mainly consists of Line supports (poles), O/H conductors, Insulators, Earth wire, small distribution transformers etc.


Insulators:
Used to protect the phase conductors reaching the grounded terminals, and as supporting elements. those are classified as:

1. Strain

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2. Pin

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3. Post

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4. Suspension

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5. Shackle

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Poles:
1. Steel poles

2. Wooden poles

3. Reinforced concrete (RC) poles

O/H Conductors:


1. All aluminium conductors (AAC)

2. All aluminum alloy conductors (AAAC)

3. Aluminum conductor, Steel reinforced (ACSR)

4. Arial bundled cables (ABC)