The primary function of the electric power distribution system in a building or facility is to receive power at one or more supply points and to deliver it to lighting, elevators, chillers, motors and all other electrical loads.  The selection of a system arrangement has a profound impact upon the reliability and maintainability of the electrical system.  Four basic circuit arrangements are used for the distribution of electric power. They are the radial, primary selective, secondary selective, and secondary network circuit arrangements.  Several commonly-used electrical distribution systems are discussed in this training session. It is usually necessary to combine two or more of these arrangements for increased system reliability.

Learning Objectives:

• Explain the benefits for each type of electrical power distribution system.
• Identify the pros and cons associate with each system.
• Describe the cost versus reliability versus redundancy of each system.

Prerequisites:

Participants should understand basic print reading and one-line diagrams.