Molded Case Circuit Breakers are used to efficiently distribute power throughout an electrical system. They provide a means to manually open or close a circuit, and are designed to protect wiring and equipment by automatically opening under an overload or short circuit condition. In the United States, most Molded Case Circuit Breakers (MCCBs) are listed …
Miniature Circuit Breaker (MCB) are designed to protect the conductors and insulation from damage due to over load and short circuit.The simplest way to visualize a miniature circuit breaker is to think of a load center in a home, the circuit breakers inside are miniature circuit breakers. Components MCBs are made up of 5 components …
The two types of low voltage (LV) busway are feeder and plug-in. They are commonly intermixed on runs of busway and plug into each other. Feeder Busway Sometimes called low impedance busway Used to feed power to a distant point Beneficial because the voltage drop over the run is generally low (somewhat lower than plug-in …
Busway is an economical, modern method of distributing electricity within a building. It is similar to the tracks that an electric model train runs upon, both in look and in function. Train track sections can be snapped together to form a number of different paths for the train to follow. Likewise, sections of busway can …
Single-phase power can be obtained from any three-phase electrical system by connecting any two phase leads. However, it is not possible to obtain three-phase power from a single-phase power source without recourse to either a rotary or static phase converter A rotary phase converter is a machine that can convert single-phase power to three phase …
If AC current and voltage were always in phase, the average power over a complete cycle would be equal to the product of the current and voltage and power could be measured in watts. However, this is a theoretical situation because there is always some reactance present in an AC circuit that keeps the current …
All of the components in an electrical system are designed to operate at their rated voltages for optimum efficiency and long service. An ideal electrical system would provide constant voltage to all customers under all conditions of load. Unfortunately, because of the unpredictable dynamics of a practical system, none is ideal. Thus, it is necessary …
The single-pole, wall-mounted toggle switch, as shown in below Figure , is the most commonly used switch in homes and offices. These wall switch wiring diagrams have the two brass screw terminals on the right side of the switch for the connection of black “hot” wires. It makes no difference which “hot” wire (input or …
The National Electrical Code (NEC 2002) provides guidance for electrical contractors and electricians, but it is really intended for use by governmental agencies that have legal jurisdiction over electrical installations and authorized electrical and insurance inspectors. The many mandatory chapters include Chapter 2, “Wiring and Protection,” Chapter 3, “Wiring Methods and Materials,” and Chapter 4, …
NEC 2002, Article 314, “Outlet, Device, Pull, and Junction Boxes; Conduit Bodies; Fittings; and Manholes,” requires that wire connections or cable splices be contained inside approved metal or plastic boxes. This provision is intended to shield wood building framing members or other adjacent flammable objects from electrical sparks should the wiring be defective. Boxes also …