Spark suppression, Physics

Spark suppression:

If we consider a circuit with a large inductance, possibly one using a magnetic relay. At the instant the switch is opened, the current through the coil is changing at maximum rate, therefore the back emf induced in the coil is also at maximum.

This emf is applied to the air gap between the switch contacts and ionises the air, producing a spark which the burns the contacts. This increases their electrical resistance and radiates energy which may cause interference, therefore sparks must be suppressed. Good design of switch contacts can help, but connecting a capacitor in parallel with the switch is the best method of eliminating sparking.

When using a capacitor the energy released by the coil charges the capacitor instead of ionising air. When the switch is closed again the capacitor discharges.

Posted Date: 9/13/2012 6:20:23 AM | Location : United States







Related Discussions:- Spark suppression, Assignment Help, Ask Question on Spark suppression, Get Answer, Expert's Help, Spark suppression Discussions

Write discussion on Spark suppression
Your posts are moderated
Related Questions
Q. What action reaction pair is responsible for pushing a car forward? Ans. The wheels push back on the ground using friction while the ground then pushes forward on the

The resultant of two forces 3P and 2P is R. If the first force is doubled then the resultant is also doubled. then the angle between the two forces us. plz xplain with the solution

The water will not spill Get a small pail and fill it nearly full with water . Swing it around rapidly at arms' length and the water will not spill because of centrifugal force

De?ne Pilling-Bed Worth rule. Write about the applications of carbon nanotubes and nanowires.

Q. How is radiation release from the body? Answer:- The body radiates energy by thermal conduction through the skin to the clothes, air, and so on around the body. A littl

Derive the mathematical expression PV r = constant for an ideal gas undergoing adiabatic reversible expansion.

Work is equal to which of the following? a) The cross product of force and displacement. b) The product of force times time c) Force divided by time d) The dot

In the following experiment, a constant-pressure calorimeter containing 100 ml of H 2 O is used. The initial temperature of the calorimeter is 24.6 o C. If 18.6 g of CaCl 2 is a

Q. In Young's double slit experiment, the width of the fringe obtained with light of wavelength 60000A is 2 mm. Calculate the fringe width if the entire apparatus is immersed in a

what are the combination of clippers ?explain with diagram