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

Ratio of velocities of two light waves, Given the ratio of velocities of tw...

Given the ratio of velocities of two light waves traveled in vacuum and having wave lengths 5000A o and 6000A o . Can you explain by working of diamonds sparkle?

Uses of radar, Uses of Radar: Radar is used to locate and recognize war...

Uses of Radar: Radar is used to locate and recognize war planes and missiles, to guide ships or submarine to see position of a satellite in space.

What value must you use for the focal length f of the lens, Presume that yo...

Presume that you are asked to find the image position in a problem involving a lens. You are specified the object position and you are told that the lens is a concave lens whose fo

Gravitational Force Word Problems, A 2.5 kg rock is located on the Earth''s...

A 2.5 kg rock is located on the Earth''s surface. If the mass of the moon is 7.4 E 22 kg, and the separation distance between the center of the rock and the center of the moon is 3

Explain isolated system, ISOLATED SYSTEM: "When a number of bodies are ...

ISOLATED SYSTEM: "When a number of bodies are like that they can exert force upon one another and no external agency exerts a force on them, they are said to form an isolated s

The mass of 1 mole of electrons is, The mass of 1 mole of electrons is: ...

The mass of 1 mole of electrons is: (1) 9.1x 10 -28 g (2) 1.008mg (3) 0.55mg (4) 9.1x 10 -27 g Ans:  (3)0.55mg

Time Period, what is the time period of a liquid in U tube ?

what is the time period of a liquid in U tube ?

Explain about the term simulated absorption in brief, Explain about the ter...

Explain about the term simulated absorption in brief. Stimulated absorption: a. For the photon-atom interaction to happen, the energy of the interacting photon h? must match

Describe the magnetic moment of a bar magnet, Describe the magnetic moment ...

Describe the magnetic moment of a bar magnet. What is its direction? Can you find two magnetic field lines intersecting? Why?

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