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

Henry, Henry; H (after W. Henry, 1775-1836): The derived SI unit of in...

Henry; H (after W. Henry, 1775-1836): The derived SI unit of inductance, described as the inductance of a closed circuit wherein an electromotive force of 1 V is generated whe

Characteristics of a transmitted pulse, Characteristics of a Transmitted Pu...

Characteristics of a Transmitted Pulse The below animation depicts the boundary behavior of a pulse that is moving along a less dense incident and medium towards that is approa

Types of modulus of elasticity, There are five types of modulus  of elastic...

There are five types of modulus  of elasticity (i) YOUNG'S MODULUS OF ELASTICITY (Y (ii) BULK MODULUS OF ELASTICITY (K) (iii) COMPRESSIBILITY (iv) MODULUS OF RIGIDITY

Formalism of synaptic plasticity, (a) Equation (3) may be viewed as a form...

(a) Equation (3) may be viewed as a formalism of synaptic plasticity - the synapse is able to change in strength in response to either use or disuse of it. We can observe the s

A see-saw lever, A see-saw lever Get a thick plank about 3 m long and b...

A see-saw lever Get a thick plank about 3 m long and bring it into the class room. Balance it over a box or some other suitable device and let the pupils experiment with the se

Similarities in construction of MOSFET and JFET, Similarities in Constructi...

Similarities in Construction of MOSFET and JFET (i)  JFET is a three terminal semiconductor device (source, drain and gate) in which current conduction is by majority carriers

Calculate the feedback fraction, Q. The gain of an amplifier without feed...

Q. The gain of an amplifier without feedback is 100 and the gain of an amplifier with feedback is 200. Calculate the feedback fraction. Solution : Voltage gain after feedba

What are steps in splicing process included, What are steps in splicing pro...

What are steps in splicing process included? Steps involved in splicing process are as follows: For a good quality splicing, the given steps are to be followed. a. Jacke

Draw a free-body diagram for the elevator, Erika is on an elevator and pre...

Erika is on an elevator and presses the button to go down. When the elevator first begins moving, it has an acceleration of 2.5 m/s 2 downward. Erika and the elevator have

Common lead acid battery faults, common lead acid battery faults: Caref...

common lead acid battery faults: Careful treatment of lead acid batteries prevents damage and early failure, however, some common faults associated with lead acid batteries are

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