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

What wavelength is formed by this pipe, An organ pipe which is open at both...

An organ pipe which is open at both ends resonates at its fundamental frequency.  Neglecting any end effects, what wavelength is formed by this pipe in this mode of vibration i

Write down the electromagnetic wave equation, Write down the electromagneti...

Write down the electromagnetic wave equation for free space in terms of electric field.

Magnetic field is zero, Two parallel wires P and Q situated at a separation...

Two parallel wires P and Q situated at a separation of 6 cm carry electric currents i 1 =5 A and i2 = 2 A in opposite directions as given in fig-. Determine the point on the line

Determine the combined stress distribution, A universal column of 6m carrie...

A universal column of 6m carries a Point Load of (180+n2) kN centrally at its axis. The column also carries one end of a simply supported beam of 5m with a uniformly distributed lo

Explain the energy, Explain the Energy Again, we have all heard about e...

Explain the Energy Again, we have all heard about energy. When the alarm clock rings in the morning we roll over and say, “I do not want to get up, I have no energy this mornin

Specific heat, why specific heat is different at different temperature?

why specific heat is different at different temperature?

Acceleration due to gravity, Who was the first person to show that all obj...

Who was the first person to show that all objects fall toward Earth with constant _________.

Heat transfer, what condition is necessary for heat transfer occur

what condition is necessary for heat transfer occur

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