Distribution transformers reduce the voltage of the
primary circuit to the voltage required by customers. This voltage varies
and is usually:
- 120/240 volts single phase for residential customers,
- 480Y/277 or 208Y/120 for commercial or light industry customers.
Three-phase pad mounted transformers are used with an
underground primary circuit and three single-phase pole type transformers
for overhead service.
Network service can be provided for areas with large concentrations of
businesses. These are usually transformers installed in an underground
vault. Power is then sent via underground cables to the separate customers.
 Figure 1. Air Distribution transformer - commercial facility
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 Figure 2.
Industrial facility distribution transformer
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Figure 3.
Residential distribution transformer |
 Figure 4.
Pad-mounted residential distribution transformer
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