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

Electricity, help by post offoce box explan rasistance of a wire

help by post offoce box explan rasistance of a wire

Atomic Physics, Assignment Just question and answer Quotation; how much

Assignment Just question and answer Quotation; how much

What is the magnitude of the component, A 105-N suitcase sits on a rubber r...

A 105-N suitcase sits on a rubber ramp at an airport carousel at a 25° angle. The weight vector can be broken into two perpendicular components. a. What is the magnitude of the

What are mass defect and binding energy, What are mass defect and binding e...

What are mass defect and binding energy? How is mass defect related to binding energy? Describe the term ‘decay constant' for a radioactive substance. Reduce the relation betwee

What is meant by the rest mass energy of an electron, What is meant by the ...

What is meant by the rest mass energy of an electron? According to the Einstein's Theory of Relativity, the mass of a body (say a particle) occurs on the energy and on the mom

Motion, a rocket is launched at an angle 53 degree to the horizontal with a...

a rocket is launched at an angle 53 degree to the horizontal with a speed of 100 m/s. it moves along its initial line of motion with an acceleration of 30m/s for 3 seconds. at thi

Explain kirchoff"s current law, Kirchoff"s Current Law states that in any ...

Kirchoff"s Current Law states that in any electrical network, the algebraic sum of the currents  meeting at a point (or junction) is zero, which means that the total current leavi

Bohr magneton, Bohr magneton (N. Bohr) It is the quantum of magnetic mo...

Bohr magneton (N. Bohr) It is the quantum of magnetic moment. Bohr radius (N. Bohr) It is the distance corresponding to the mean distance of an electron through the nuc

Why nichrome is used as heating element, Q. Why nichrome is used as heating...

Q. Why nichrome is used as heating element in electric heating devices? Nichrome, an alloy of nickel as well as chromium is used as the heating element for the following reaso

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