Electricity has helped transform many of the worlds societies from agricultural based economies to industrialized urban centers with infrastructures that feed of the energy it provides. The increase in manufacturing industries has created the need for inventions and adaptions to harness and distribute electricity safely. One of these inventions is the Siemens bus plug.

A Siemens bus plug and bus plug duct act as the gateway in and out of a a power distribution system such as a distribution substation and offer their own circuit protection. A medium voltage switchgear can offer similar protection. A Siemens bus plug in combination with a non segregated phase bus duct have its own circuit protection via a fuse or a circuit breaker. Measured in volts or voltage, U.S. bus plug voltage range from 120 over 240, 208 over 120, 240, 277 over 480, 480, or 600 volts. A Siemens bus plug lessens the number of feeds coming off of electrical switchboards. Bus plug ampere ratings can range from 15 to 1600 amps in the U.S.

Bus plugs often need replacement because of the demanding environments in which they are used. Manufacturing environments, for example, often have high temperatures and high quantities of air contaminants, which shorten the life span of a bus plug.