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
Collins Discovery Encyclopedia, 1st edition © HarperCollins Publishers 2005

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.
Illustrated Dictionary of Architecture Copyright © 2012, 2002, 1998 by The McGraw-Hill Companies, Inc. All rights reserved

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.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

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.
McGraw-Hill Dictionary of Architecture and Construction. Copyright © 2003 by McGraw-Hill Companies, Inc.

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.
An Illustrated Dictionary of Aviation Copyright © 2005 by The McGraw-Hill Companies, Inc. All rights reserved
References in periodicals archive ?
? The scene of the collision on the Chester to Crewe railway line near Cholmondeston and (inset) the ballast distributor involved
Ballast-Check 2 is a small, lightweight, highly durable handheld fluorometer ideal for quick indicative compliance checks of ballast water.
More particularly, a distinct loading program is necessary to characterize the ballast behavior subjected to dynamic reciprocated changes in track configurations since it allows reproduction of testing conditions that are very close to the service ones.
The D-1 standard requires ships to exchange their ballast water in open seas, away from coastal waters.
View of Swan Hunter from Hebburn ballast hill in 1964, from Hebburn Through Time by Derek Dodds.
"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.
In the newly developed ballast water management system, called "ATPS-BLUE sys", an electrolysis unit is placed in the main ballast water pipe.
| MANAMA, Dec 5 (KUNA) -- The ministers and senior officials in charge of environment affairs in the Gulf Cooperation Council (GCC) unveiled Thursday plans to join the International Convention for the Control and Management of Ships' Ballast Water and Sediments (BWM) to protect the marine environment in the Arabian Gulf.
Ballast Nedam N.V (FRA:BNZ.F) (AMS:BALNE.AS) announced today plans to build its first 700-bar hydrogen refuelling station for the Flemish-Dutch WaterstofNet.
The Asian ballast water treatment systems market is highly lucrative and is expected to show tremendous growth over the next 6 - 7 years.
International Resource News-February 21, 2013--State Systems selects Green Ballast's daylight harvesting fluorescent light ballasts(C)1994-2013 ENPublishing - http://www.enpublishing.co.uk
Organisms, including Vibrio cholerae, can be transferred between harbors in the ballast water of ships.