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

How much does the temperature rise, When a driver brakes an automobile, the...

When a driver brakes an automobile, the friction between the brake drums and the brake shoes converts the car's kinetic energy to thermal energy. If a 1450 kg automobile traveling

What are solid core or multicore, What are Solid core or multicore? It ...

What are Solid core or multicore? It will depend on the use to that the optic is put and the actual installation conditions. Solid core optics has usually, a larger bending rad

Evaluate the percent error, Q When calculate Planck's constant, a student's...

Q When calculate Planck's constant, a student's calculations produce values of 5.78 × 10 -34   J·s and 7.29 × 10 -34 J·s. If the accepted value is 6.63 × 10 -34  J·s, what is

Young'';s Moudulus, filled observation of youngs modulus using searles appa...

filled observation of youngs modulus using searles apparatus?

What is nucleus, What is nucleus?               It is the type of an ato...

What is nucleus?               It is the type of an atom where whole mass of the atom is supposes to be concentrated. Or it is the central part of an atom which have proton and

Explain spring force (fspring), Explain Spring Force (Fspring) Force ex...

Explain Spring Force (Fspring) Force exerted by a compressed or stretched spring upon any object that attached to it. An object that compresses or stretches a spring is always

Fermi dirac statistics, It determines the probability of an electron occupy...

It determines the probability of an electron occupying a state at an energy level E. This takes into account that a collection of electron must obey the Pauli Exclusion Principle.

Magnification in scanning electron microscope, How is magnification in scan...

How is magnification in scanning electron microscope controlled? Magnification in scanning electron microscope: Magnification into a SEM (scanning electron microscope) can b

Which material has the highest melting point, Which of the following materi...

Which of the following material has the highest melting point (A) Copper. (B) Aluminium. (C) Tungsten. (D) Gold. Ans: Tungsten has the highest melting point.

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