Search results
Results from the WOW.Com Content Network
In contrast to a simple light switch, which is a single pole, single throw (SPST) switch, multiway switching uses switches with one or more additional contacts and two or more wires are run between the switches. When the load is controlled from only two points, single pole, double throw (SPDT) switches are used.
Tamper-resistant automotive ignition switches discourage car theft. Vandal-resistant switches are often low-voltage, low current, so-called "signal" types intended to trigger a change in state, perhaps from "off" to "on" and vice versa. The mechanical types often have gold-plated contacts that do not corrode, to allow reliable low-power ...
The 20 A plug has a blade rotated 90° (opposite blade from what would be the "line" blade on a 2-15 or 5-15 plug. This prevents accidental insertion of plugs into outlets that use different voltages), and the 6-20R receptacle has a T-shaped hole to accept both 6-15P and 6-20P plugs (similar to the 5-20R receptacle accepting 5-15P and 5-20P plugs).
The toggle light switch was invented in 1916 by William J. Newton. [2] As a component of an electrical wiring or home wiring system, the installation of light switches is regulated by some authority concerned with safety and standards. In different countries the standard dimensions of the wall mounting hardware (boxes, plates, etc.) may differ.
Weather-resistant. Protects against falling dirt and windblown dust, against weather hazards such as rain, sleet and snow, and is undamaged by the formation of ice. Used outdoors on ship docks, in construction work, and in tunnels and subways. 3R: As 3, but omits protection against windblown dust. 3S: As 3, but also operable when laden with ice.
Lighting and general purpose receptacles are at 120 volts AC, with larger devices fed by three wire single-phase circuits at 240 volts. In commercial construction, three-phase circuits are often used. Common 3 phase configurations within a building are 208v/120 wye, 120/240 center tapped delta and 480v/277v wye. Lighting is usually fed by 277 V ...
The term plug is in general and technical use in all forms of English, common alternatives being power plug, [1] electric plug, [2] and (in the UK) plug top. [3] The normal technical term (in both British and International English) for an AC power socket is socket-outlet , [ 4 ] but in non-technical common use a number of other terms are used.
A residual-current device (RCD), residual-current circuit breaker (RCCB) or ground fault circuit interrupter (GFCI) [a] is an electrical safety device, more specifically a form of Earth-leakage circuit breaker, that interrupts an electrical circuit when the current passing through line and neutral conductors of a circuit is not equal (the term residual relating to the imbalance), therefore ...