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

Briefly explain the conditions of interference fringes, Briefly explain the...

Briefly explain the conditions for clear vision of interference fringes.

Relative veloctiy, The velocity of a motor boat with respect to Still Water...

The velocity of a motor boat with respect to Still Water is 7 m/s and the velocity of water in river is 3 m/s. When the boat starts moving upstream, a float was dropped from it.

#title.laws of motion., in which case there is change in acceleration in ca...

in which case there is change in acceleration in case of pulley?

Proton was discovered, Proton was discovered by: (1)Chadwick (2)Thom...

Proton was discovered by: (1)Chadwick (2)Thomson (3)Goldstein (4)Bohr Ans: (3)Goldstein

Planck constant, Planck constant; h: The fundamental constant equivale...

Planck constant; h: The fundamental constant equivalent to the ratio of the energy of a quantum of energy to its frequency. It refer to the quantum of action. This contains th

Factor, Discuss the Factor affecting limiting current.

Discuss the Factor affecting limiting current.

Find the value of g by free fall method, initial position time the vibra...

initial position time the vibration mean time time period of the bob t time

Explain non-viscous flow, Viscosity in fluids is the analog of friction in ...

Viscosity in fluids is the analog of friction in solids. Both are methods by which the kinetic energy of moving bodies can be changed into thermal power. In the absence of friction

Time dilation, a spacecraft is moving relative to the earth. an observer fi...

a spacecraft is moving relative to the earth. an observer finds that according to her clock 3601 seconds elapse between 1pm and 2pm on the spacecrafts clock. what is the spacecraft

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