Metallised paper capacitors, Physics

Assignment Help:

One side of impregnated paper capacitors is sprayed with metal.  When such paper is rolled, its gives higher capacitance for a given value. This capacitor has a self healing property, if the voltage across the capacitor is gradually raised to a value at which sparking occurs, the voltage is held constant at this value, and then the sparking is only momentary. This sparking at week points in paper and thin metal film evaporates from these spots without damaging the paper. Aluminium at high temperatures produces aluminium oxide, which is a good insulator. Aluminium is evaporated on lacquered paper tissue in vacuum. Thickness of film is small. Metallised tissue is passed between metal rollers, across which working voltage is applied to remove week points. Two such tissues are superimposed and wound to form a roll. The demutualised margin serves as insulator between the two electrodes. Both the ends are sprayed with copper so that end connections can be made.

SPECIFICATIONS

Range of values                                  1000 Pf to 1 μF

Tolerances                                                                          25%

Voltage rating up to                                                             1.5 KV

Power factor at 1K Hz                               0.05

Stability                                                                              5 to 10%

Temperature coefficient                                 + 150 to 200 ppm/0C

APPLICATIONS: It is used for decoupling.


Related Discussions:- Metallised paper capacitors

Thermal expansion, When a body is heated, it expands in terms of area, leng...

When a body is heated, it expands in terms of area, length & temperature and volume rises. In a solid, molecules may only have thermal agitation. As temperature of a object enhance

Electricity, Derive expression for total power consumed when three applianc...

Derive expression for total power consumed when three appliances of power p1 p2 nd p3 are connected in series.

Determine joules of heat if energy dissipated by resistor, The potential di...

The potential difference across a 4 ohm resistor is 20 volts.  Assuming that all of the energy dissipated by this resistor is in the form of heat, how many joules of heat are radia

Determine relative permeability of a paramagnetic substance, The relative p...

The relative permeability of a paramagnetic substance is (A) Unity.         (B) Slightly more than unity. (C) Zero.           (D) less than unity. Ans: The relativ

Are machines with the ce mark certified, Are machines with the CE mark cert...

Are machines with the CE mark certified? The CE mark was a good concept in its inception but this has been so much abused which has become practically meaningless for the end u

Moving coil galvanometer, what would be the introduction to a moving ciol g...

what would be the introduction to a moving ciol galvanometer

What do you mean by photo electric effect, What do you mean by photo electr...

What do you mean by photo electric effect? Show the laws of photoelectric effect. Illustrate these laws using Einstein's equation of photo electric effect?

Tools for performance measurement in parallel algorithm, After the parallel...

After the parallel algorithm has been written as well as executed performance of both algorithms is one of other main concerns. In order to examine performance of algorithms there

What is splicing, What is splicing? Splicing: Two optical fibers uti...

What is splicing? Splicing: Two optical fibers utilized for communication are joined with a process termed as Splicing. This must be done very carefully that is the splicing

Non-horizontally launched projectiles, Non-Horizontally Launched Projectile...

Non-Horizontally Launched Projectiles Assume a cannonball being launched at an angle from cannon atop an extremely high cliff. Suppose as well in which the cannonball does not

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