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

Determine the voltage drop across the load, For the circuit shown in Figure...

For the circuit shown in Figure, calculate the current flowing in the 50Ω load and the voltage drop across the load when (a) XS is 3/5 of XY (b) point S coincides with point

Kinematic, A sprinter runs 100.0 m. If he travels at constant acceleration ...

A sprinter runs 100.0 m. If he travels at constant acceleration of 1.95 m/s2 for the first 6.00 s, and then at constant velocity for the remaining time, what was his average veloci

What are the particles that make up an atom, Q. Illustrate what are the thr...

Q. Illustrate what are the three particles that make up an atom? Answer:- Atoms are conjured of neutrons, protons, and electrons. The protons as well as neutrons are found

Define core type transformers, Core type Transformers: In this type of ...

Core type Transformers: In this type of transformer the windings enclose the core (fig. given below). Both the windings are divided and half of every winding is placed on eac

Kohlrauschs law, Kohlrausch's law (F. Kohlrausch): If a salt is dissol...

Kohlrausch's law (F. Kohlrausch): If a salt is dissolved into water, the conductivity of the solution is the total of two values one based on the positive ions & the other dep

What are uses of ultra-violet radiations, Q. What are uses of ultra-violet ...

Q. What are uses of ultra-violet radiations? Uses of ultra-violet radiations: (i) They are utilized to destroy the bacteria and for sterilizing surgical instruments.

Keplers second law, Keplers Second Law After studying a wealth of plane...

Keplers Second Law After studying a wealth of planetary data for the motion of the planets about the sun, Johannes Kepler reasons three laws of planetary motion. Kepler's secon

Experiment of a simple pendulum, A simple pendulum Tie a cord at least ...

A simple pendulum Tie a cord at least 2 m long to some object like a stone or a small metal ball. Suspend this in a doorway or from a hook in the ceiling and begin it swinging

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