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Mercury switches have one or more sets of electrical contacts in a sealed glass envelope that contains a small quantity of mercury. Tilting the switch in the opposite direction moves the mercury away from that set of contacts, breaking that circuit.
What uses a mercury switch?
Mercury switches are used in a variety of consumer, commercial, and industrial products, including appliances, space heaters, ovens, air handling units, security systems, leveling devices, and pumps.
Is mercury still used in switches?
Slightly more mercury was used in switches than in relays during all three reporting years.Mercury Use in Switches and Relays. Float Switch (from a sump pump) Tilt Switch (from a washing machine) Flame Sensor (from a gas range) Photographs Source: Vermont Agency of Natural Resources.
What is a mercury tilt switch used for?
Similar to a tilt switch, a mercury switch is used to detect slight inclinations of a large angle. A mercury switch (also known as a mercury tilt switch) is a switch which opens and closes an electrical circuit through a small amount of liquid mercury.
How does a non mercury tilt switch work?
You may see many tilt switches today labelled as “non-mercury”. This is because tilt switches in the past, and some today, operate by opening and closing the switch using a small piece of mercury to close the circuit.
Do old light switches have mercury?
Manufactured prior to 1991, by many manufacturers, mercury light switches (generally referred to as “silent switches”) contain about 2 grams of mercury. Mainly found in older buildings, these devices look like typical wall switches, but they do not make the audible “click” sound when activated.
How do you test a mercury switch?
Touch the probes to the two leads when you put your multimeter into continuity-test mode. The angle at which the switch opens and closes is determined by tilt. The switch is not continuity when pointing down.
Who invented the mercury switch?
In the 1910s Phelan invented and developed various forms of the mercury switch, on which he obtained 52 patents.
When did they stop making mercury light switches?
Manufacturing was discontinued in the late 1980s because of concern over the health effects of mercury. Mercury tilt switches also may be found in appliances that have interior lights activated by opening a lid. If you can’t see a mechanical on/off connection, there may be an embedded mercury switch.
How does white mercury look like?
Elemental or metallic mercury is a shiny, silver-white metal, historically referred to as quicksilver, and is liquid at room temperature.
How do mercury relays work?
Mercury relays consist of a vertical (usually glass) tube containing liquid mercury. They have isolated contacts at the bottom of the tube and partway up, usually in a side arm of the glass. The relay works by displacement. When energised, this coil attracts the slug, lifting it upwards and out of the mercury pool.
What element is used in a mercury switch?
Mercury tilt switch (position sensor) is a glass container (tube) with two or more electrodes containing mercury (Hg). Mercury, one of only two liquid elements, forms the liquid conductor.
How is mercury used in electronics?
Electronics. Mercury is used in LCD screens and monitors. It is also used in laptop screen shutoffs. Televisions manufactured before 1991 may also contain mercury switches.
How does a tilt switch operate?
Tilt sensors are switches that can detect basic motion/orientation. The metal tube has a little metal ball that rolls around in it, when its tilted upright, the ball rolls onto the contacts sticking out of end and shorts them together.
What is a mercury tilt sensor?
The Mercury Tilt Sensor Switch is a switch that opens and closes an electrical circuit through a small amount of liquid mercury. When the module tilts, it outputs low and the corresponding LED lights up.
How much mercury is in a switch?
How Much Mercury is in a Light Switch? A mercury light switch contains about one drop of mercury.
Where does liquid mercury come from?
Mercury, a liquid metal – once widely referred to as quick silver – is a naturally occurring element released by volcanoes and the weathering of rocks. But most of the mercury that is responsible for polluting Minnesota lakes and the fish that live in them originates as air pollution from coal-burning power plants.
What is a limit switch?
A limit switch is an electromechanical device operated by a physical force applied to it by an object. Limit switches are used to detect the presence or absence of an object. These switches were originally used to define the limit of travel of an object, and as a result, they were named Limit Switch.
How do you test a Mercury outboard power pack?
How to Test a Mercury Power Pack Note the routing and connection points, then disconnect the primary wire or wires from the ignition coil. Select the resistance scale on the multimeter. Repeat the process to ensure that you only probed the proper wires and connectors if tests are out of specification.
Is mercury still used in cars?
Despite practical, inexpensive alternatives and industry commitments to phase out its use, mercury continues to be widely used in new automobiles. Mercury is highly toxic to humans and wildlife and is released when automobiles are scrapped.
What are mercury pellets used for?
Mercury switches were widely used in the automotive industry for trunk lid lights, open door indicators, and anti-lock braking systems, but due to the harmful effects mercury has on the environment their use was discontinued in all American-made cars in 2003.
What happens when mercury touches gold?
That is, if it touches gold it will immediately break the lattice bonds of the precious metal and form an alloy in a process known as amalgamation. Nov 18, 2017.
Is it OK to touch mercury?
Mercury is a very toxic or poisonous substance that people can be exposed to in several ways. If it is swallowed, like from a broken thermometer, it mostly passes through your body and very little is absorbed. If you touch it, a small amount may pass through your skin, but not usually enough to harm you.
Does mercury destroy gold?
Mercury dissolves many metals such as gold and silver to form amalgams.
