Spark suppression, Physics

Assignment Help:

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.


Related Discussions:- Spark suppression

Explain magnetic dipole moment., Consider a current loop where the circulat...

Consider a current loop where the circulating current is I. This may be for an example of a coil carrying a current. We will assume that the current loop lies within a single plane

How fast must a ring rotate, If a ring were constructed as knid of a space...

If a ring were constructed as knid of a space station. How fast must a 50.0-m-radius ring rotate to simulate Earth's gravity?

Kl, #quuiujiestion..

#quuiujiestion..

Physics Question, Two friends are at the local high school track, a circle ...

Two friends are at the local high school track, a circle measuring 440 yards for one complete lap. Abe can jog at 8.2 miles per hour while Bob’s jogging speed is 4.6 miles per hour

Explain the process of phase changes, Explain the Process of Phase Changes ...

Explain the Process of Phase Changes Matter exists in three forms: as a solid, a liquid or as a gas. These are called phases of matter. If we take a chunk of ice (solid water) fr

Find also the power rating of the kettle - conductors, An electric kettle h...

An electric kettle has a resistance of30?. What current will ?ow when it is connected to a 240V supply? Find also the power rating of the kettle   A current of 5A ?ows i

What are intrinsic and extrinsic semiconductors, What are intrinsic and ext...

What are intrinsic and extrinsic semiconductors? A semiconductor is a material that has an electrical conductivity among that of a conductor and an insulator. In a semiconducto

Experiment of a single fixed pulley, A single fixed pulley Set up a one...

A single fixed pulley Set up a one fixed pulley as shown in the diagram below. By means of weights see how much force is needed to lift weights of 25, 50, 75, 100 and 200 g. Ca

Optic fiber, why the reflective index of cladding is lower then in core of ...

why the reflective index of cladding is lower then in core of a fiber optic?

Object located at the center of curvature- ray diagrams, Ray Diagrams for C...

Ray Diagrams for Concave Mirrors Object Located At the Center of Curvature: Ray diagrams are meaningful tools for denoting the location of an image as generates through a con

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd