Search results
Results from the WOW.Com Content Network
Two control knobs for a heating/cooling system. The left knob controls the temperature while the right controls the fan speed. A control knob is a rotary device used to provide manual input adjustments to a mechanical/electrical system when grasped and turned by a human operator, so that differing extent of knob rotation corresponds to different desired input.
The Carter system, also known as the Chicago system, was a method of wiring three-way switches in the era of early knob-and-tube wiring. This now-obsolete wiring method has been prohibited by the USA National Electrical Code since 1923, [2] even in new knob-and-tube installations which are still permitted under certain circumstances. This ...
First-generation wiring systems became susceptible to abuse by homeowners who would replace blown fuses with fuses rated for higher current. This overfusing of the circuits subjects wiring to higher levels of current and risks heat damage or fire. Knob-and-tube wiring may also be damaged by building renovations. [11]
This exhaust fan's operation is interlocked with the concentration of contaminants emitted by internal combustion engines. Mechanical, or forced, ventilation is provided by an air handler (AHU) and used to control indoor air quality. Excess humidity, odors, and contaminants can often be controlled via dilution or replacement with outside air ...
Get AOL Mail for FREE! Manage your email like never before with travel, photo & document views. Personalize your inbox with themes & tabs. You've Got Mail!
A user can even supplement this function with additional cooling components or connect a manual fan controller with knobs that set fans to different speeds. [1] In the IBM PC compatible market, the computer's power supply unit (PSU) almost always uses an exhaust fan to expel warm air from the PSU.
The switch box is covered by a decorative plate. The first light switch employing "quick-break technology" was invented by John Henry Holmes in 1884 in the Shieldfield district of Newcastle upon Tyne. [1] The "quick-break" switch overcame the problem of a switch's contacts developing electric arcing whenever the circuit was opened or closed.
Common circuit diagram symbols (US ANSI symbols) An electronic symbol is a pictogram used to represent various electrical and electronic devices or functions, such as wires, batteries, resistors, and transistors, in a schematic diagram of an electrical or electronic circuit. These symbols are largely standardized internationally today, but may ...