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

Define the physical significance of damping coefficient, Define the physica...

Define the physical significance of damping coefficient and how can we caluclate it? What is its unit

Hvac, determine the pressure of a 20 lb force applied to an area of 10 inch...

determine the pressure of a 20 lb force applied to an area of 10 inch squared

State and explain flemings left hand rule, What is the net force on a condu...

What is the net force on a conductor of length l carrying current 'i' when it is situated in a magnetic field of induction B? When is it maximum? State and explain Fleming's l

Ohms law, Ohm's law (G. Ohm; 1827): The ratio of the potential differe...

Ohm's law (G. Ohm; 1827): The ratio of the potential difference among the ends of a conductor to the current passing through it is constant; the constant of proportionality is

Intersections, about beam intersection in gama and alpha beam?

about beam intersection in gama and alpha beam?

What is dychroic filter, What is dychroic filter? A thin flat piece of ...

What is dychroic filter? A thin flat piece of glass along with a metal deposition in one of the surfaces applied into a high vacuum environment. There metal layer, only some at

Does weight influence how far you jump, For the same leg strength / jumping...

For the same leg strength / jumping technique weight affects how far one can jump. Acceleration = Force / Mass With more mass you can't accelerate yourself as much when you j

IR frequencies of various functional groups, What are the ir frquencies of ...

What are the ir frquencies of various functional groups

Newton rings, on newtons ring determine the refractive indexl of a liquid

on newtons ring determine the refractive indexl of a liquid

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