A staircase timer is an electrical switch used to control lighting on a staircase, corridor or lobby. A single action turns on the lights and they remain on for long enough to ascend or descend the stairs. The lights then turn themselves off automatically.
In a single occupancy domestic dwelling it is usual to provide multiple switching locations. The lights may be turned on or off from either the top, bottom or intermediate floors of the staircase. They remain on until turned off manually.
In a multiple occupancy dwelling, the drawback is that the cost of shared lighting is usually paid by the landlord. Individual tenants turn lights on, but have little reason to turn them off. Particularly so in the days of incandescent lamps this could be an appreciable cost. For this reason shared dwellings favour timers for staircases instead. [1] The lights are turned on by a push-button switch on any floor. They remain on automatically for an adequate time to climb the stairs, then turn themselves off.
To provide longer lighting times when required the button may be pressed repeatedly. For this reason any timer should be a retriggerable monostable, i.e. the off delay lasts from the time of the last button press. There may also be a switch, sometimes a key switch, that can turn the lights on indefinitely for tasks such as cleaning.
The first staircase timers were pneumatic pushbuttons. A large push-button, distinctly larger than a normal electrical switch, is pressed manually. An internal mechanism provides the delay. The internal piston is depressed by the button and holds the electrical contacts closed. This piston is spring-loaded to return upwards but is prevented from returning quickly by a pneumatic dashpot. This dashpot provides the timing function. [2] [3]
An electronic timer allow simple push-buttons to be used. One timer is installed controlling the lights and any number of push-buttons, without pneumatic timers and connected in parallel, are used to trigger it. [1] [4] With many push-buttons, the cost savings for equipment may be substantial.
PIR sensors may be used to control lighting in such areas. They avoid the need to press a push-button but otherwise operate as for electronic timers. As PIR sensors are not perfectly reliable a timer is needed to avoid the lights flashing off and on as the occupier moves out of detector range. The timer interval is short though compared to a push-button timer; it times the interval between sightings of the occupier, not the time of occupancy.
Such sensors are also used for restrooms. Owing to the variability of occupancy time in a restroom, a simple fixed timer was unworkable. This ability to cope with variably occupancy times is also useful when stairwells, lift lobbies and corridors must grant disabled access as they no longer discriminate in favour of an assumed transit time for an able-bodied person.
A relay is an electrically operated switch. It consists of a set of input terminals for a single or multiple control signals, and a set of operating contact terminals. The switch may have any number of contacts in multiple contact forms, such as make contacts, break contacts, or combinations thereof.
In electrical engineering, a switch is an electrical component that can disconnect or connect the conducting path in an electrical circuit, interrupting the electric current or diverting it from one conductor to another. The most common type of switch is an electromechanical device consisting of one or more sets of movable electrical contacts connected to external circuits. When a pair of contacts is touching current can pass between them, while when the contacts are separated no current can flow.
X10 is a protocol for communication among electronic devices used for home automation (domotics). It primarily uses power line wiring for signaling and control, where the signals involve brief radio frequency bursts representing digital information. A wireless radio based protocol transport is also defined.
In electrical wiring, a light switch is a switch most commonly used to operate electric lights, permanently connected equipment, or electrical outlets. Portable lamps such as table lamps may have a light switch mounted on the socket, base, or in-line with the cord. Manually operated on/off switches may be substituted by dimmer switches that allow controlling the brightness of lamps as well as turning them on or off, time-controlled switches, occupancy-sensing switches, and remotely controlled switches and dimmers. Light switches are also found in flashlights, vehicles, and other devices.
An emergency light is a battery-backed lighting device that switches on automatically when a building experiences a power outage. Emergency lights are standard in new commercial and high occupancy residential buildings, such as college dormitories, apartments, and hotels. Most building codes require that they be installed in older buildings as well.
A push-button or simply button is a simple switch mechanism to control some aspect of a machine or a process. Buttons are typically made out of hard material, usually plastic or metal. The surface is usually flat or shaped to accommodate the human finger or hand, so as to be easily depressed or pushed. Buttons are most often biased switches, although many un-biased buttons still require a spring to return to their un-pushed state. Terms for the "pushing" of a button include pressing, depressing, mashing, slapping, hitting, and punching.
A dashpot is a mechanical device, a damper which resists motion via viscous friction. The resulting force is proportional to the velocity, but acts in the opposite direction, slowing the motion and absorbing energy. It is commonly used in conjunction with a spring. The process and instrumentation diagram (P&ID) symbol for a dashpot is
In 1920 PIR SENSOR was invented by Herbert Berman. It was great contribution in motion detection field. A passive infrared sensor is an electronic sensor that measures infrared (IR) light radiating from objects in its field of view. They are most often used in PIR-based motion detectors. PIR sensors are commonly used in security alarms and automatic lighting applications.
Building automation is the automatic centralized control of a building's heating, ventilation and air conditioning, lighting and other systems through a building management system or building automation system (BAS). The objectives of building automation are improved occupant comfort, efficient operation of building systems, reduction in energy consumption and operating costs, and improved life cycle of utilities.
A motion detector is an electrical device that utilizes a sensor to detect nearby motion. Such a device is often integrated as a component of a system that automatically performs a task or alerts a user of motion in an area. They form a vital component of security, automated lighting control, home control, energy efficiency, and other useful systems.
A lighting control system is an intelligent network based lighting control solution that incorporates communication between various system inputs and outputs related to lighting control with the use of one or more central computing devices. Lighting control systems are widely used on both indoor and outdoor lighting of commercial, industrial, and residential spaces. Lighting control systems serve to provide the right amount of light where and when it is needed.
Over illumination is the presence of lighting intensity higher than that which is appropriate for a specific activity. Over illumination was commonly ignored between 1950 and 1995, especially in office and retail environments. Since then, however, the interior design community has begun to reconsider this practice. Over illumination encompasses two separate concerns:
An occupancy sensor is an indoor motion detecting device used to detect the presence of a person to automatically control lights or temperature or ventilation systems. The sensors use infrared, ultrasonic, microwave, or other technology. The term encompasses devices as different as PIR sensors, hotel room keycard locks and smart meters. Occupancy sensors are typically used to save energy, provide automatic control, and comply with building codes.
A pneumatic circuit is an interconnected set of components that convert compressed gas into mechanical work. In the normal sense of the term, the circuit must include a compressor or compressor-fed tank.
A time switch is a timer that operates an electric switch controlled by the timing mechanism.
Vandal-resistant switches are electrical switches designed to be installed in a location and application where they may be subject to abuse and attempts to damage them, as in the case of pedestrian crossing switches. Vandal-resistant switches located on devices that are outdoors must be able to withstand extreme temperatures, dust, rain, snow, and ice. Many vandal-resistant switches are intended to be operated by the general public, and must withstand heavy use and even abuse, such as attempts to damage the switch with metal tools. These switches must also resist dirt and moisture.
A placebo button is a push-button or other control which has apparent functionality but has no physical effect when pressed. Such buttons can appear to work, by lighting up or otherwise reacting, which rewards the user by giving them an illusion of control. They are commonly placed in situations where it would have once been useful to have such a button but the system now operates automatically, such as a manual thermostat in a temperature-regulated office. Were the control removed entirely, some users would feel frustrated at the awareness they were not in control.
Smart lighting is a lighting technology designed for energy efficiency. This may include high efficiency fixtures and automated controls that make adjustments based on conditions such as occupancy or daylight availability. Lighting is the deliberate application of light to achieve some aesthetic or practical effect. It includes task lighting, accent lighting, and general lighting.
The first automatic timer, the dashpot timer has been used in many different machines and has many variations. Pneumatic, hydraulic-action, and mercury displacement timers. Being used in a variety of things such as printing presses, motors, and even irrigation systems, the dashpot timer has seen many applications. Even in modern times with electrical and digital timers, these old mechanical timers are still in use due to their simplicity and ability to function in tough environments.
A twilight switch is an electronic component that allows the automatic activation of a lighting circuit when natural light drops in a given environment. Among a large number of uses, the most common is to enable automatic lighting of streets, roads, highways, roads, gardens, courtyards, etc., when sunlight drops below a certain level.
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