By Linda Sturdivant on February 16 2018 04:33:19
Cables for industrial, commercial and apartment buildings may contain many insulated conductors in an overall jacket, with helical tape steel or aluminium armour, or steel wire armour, and perhaps as well an overall PVC or lead jacket for protection from moisture and physical damage. Cables intended for very flexible service or in marine applications may be protected by woven bronze wires. Power or communications cables (e.g., computer networking) that are routed in or through air-handling spaces (plenums) of office buildings are required under the model building code to be either encased in metal conduit, or rated for low flame and smoke production.
Each type of switch has a different symbol and so do the various outlets. There are symbols that show the location of smoke detectors, the doorbell chime, and thermostat. On large projects symbols may be numbered to show, for example, the panel board and circuit to which the device connects, and also to identify which of several types of fixture are to be installed at that location.
Some components and symbols of wiring diagram are: Capacitor, used to store electric charge. Toggle Switch, stops the flow of current when open. Push Button Switch, momentarily allows current flow when button is pushed in, breaks current when released. Battery, stores electric charge and generates a constant voltage .Resistor, restricts current flow. Ground wire, used for protection. Circuit breaker, used to protect a circuit from an overload of current. Inductor, a coil that generates a magnetic field. Antenna, transmits and receives radio waves. Surge protector, used to protect a circuit from a spike in voltage. Lamp, generates light when current flows through. Diode, allows current to flow in one direction indicated by an arrowhead or triangle on the wire. Microphone, converts sound into electrical signal. Electrical motor. Transformer, changes AC voltage from high to low or vice versa. Headphone. Thermostat. Electrical outlet. Junction box.
Wiring diagrams use standard symbols for wiring devices, usually different from those used on schematic diagrams. The electrical symbols not only show where something is to be installed, but also what type of device is being installed. For example, a surface ceiling light is shown by one symbol, a recessed ceiling light has a different symbol, and a surface fluorescent light has another symbol.