ballast


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Related to ballast: Electrical ballast

ballast

1. any dense heavy material, such as lead or iron pigs, used to stabilize a vessel, esp one that is not carrying cargo
2. crushed rock, broken stone, etc., used for the foundation of a road or railway track
3. Electronics a device for maintaining the current in a circuit

Ballast

Power-regulating device that modifies input voltage and controls current to provide the electrical conditions necessary to start and operate gaseous discharge lamps, especially fluorescents and HID (high-intensity discharge) lamps.

ballast

[′bal·əst]
(aerospace engineering)
A relatively dense substance that is placed in the cab of a balloon and can be thrown out to reduce the load or can be shifted to change the center of gravity.
(civil engineering)
Crushed stone used in a railroad bed to support the ties, hold the track in line, and help drainage.
(electricity)
A circuit element that serves to limit an electric current or to provide a starting voltage, as in certain types of lamps, such as in fluorescent ceiling fixtures.
(materials)
Coarse gravel used as an ingredient in concrete.
(naval architecture)
A relatively heavy material such as lead, iron, or water placed in a ship to ensure stability or to maintain the proper draft or trim.
To pump seawater into empty fuel tanks of a ship to ensure its stability or suitable draft and trim for seaworthiness.

ballast

1. Coarse stone, gravel, slag, etc., used as an underlayer for poured concrete.
2. A device used to provide the required starting voltage and operating current for fluorescent, mercury, or other electric-discharge lamps.
3. Class P: A ballast for a fluorescent lamp which meets the requirements of the Underwriters’ Laboratories, Inc.; includes an automatic resetting thermal protector to remove the ballast from the circuit if its temperature exceeds a specified value.

ballast

Weight installed in an airplane to ensure that the center of gravity is always within the permissible limits. In some aircraft, fuel is used as a ballast. This fuel, however, cannot be burned by the aircraft.
References in periodicals archive ?
The D-1 standard requires ships to exchange their ballast water in open seas, away from coastal waters.
We believe in the vision that Jack and his team have created and we're excited to welcome Ballast Point, to the Constellation Brands family," Mr.
Panasonic's new ballast water management system will be on display at the exhibition of "SEA JAPAN 2014" to be held at Tokyo Big Sight (East Halls 1 and 2) from April 9 to 11, 2014.
However, eventually most ships will need to install an on-board ballast water treatment system.
Assume that you turn off a lighting system 25% of the time, allowing the lighting ballasts and lamps to last 25% longer.
In the interim, the BWM Convention requires that, whenever possible, ships conduct ballast water exchange >200 nautical miles from the nearest land and in water >200 m deep.
Thirty-plus-year-old magnetic ballasts with PCBs leaked in school buildings in New York City and the states of Washington, Massachusetts and others causing hazmat conditions.
The evening-primrose, seen on the Cob and in the Borth y Gest area, is considered to have arrived here from America in the ballast of sailing ships, as also occurred with Welsh mudwort, from the north-east coast of the US, which is seen in muddy pools on parts of the marsh.
The primary objective of the present paper is to show the energy saving potential of the retrofit CDM lamps and the savings obtained on the lamp and ballast system.
The quad-tap core and coil ballast is compatible with most existing 250W luminaires and is fully compliant with the latest version of California Title 20 legislation, governing the energy efficiency standard for metal halide luminaires sold in California since the beginning of this year.
Existing machines remove degraded ballast with the track still in place through a chainsaw-like device that moves underneath the track.
About a third of the 186 invasive species in the Great Lakes are thought to have entered on oceangoing ships in the ballast water they take on for stabilization when carrying little or no cargo Zebra and quagga mussels from the Black Sea clog intake structures for municipal water systems and power plants.