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

What is waveguide dispersion in optical fibres, What is waveguide dispersio...

What is waveguide dispersion in optical fibres? Waveguide dispersion (Δτ w ): Waveguide dispersion occurs because of the dependence onto the velocity of propagation of every

Dipole moment, Isn't there any relation to calculate the dipole moment from...

Isn't there any relation to calculate the dipole moment from the electronegativities of the participating atoms? Solution) formulae:-        16(X A -X B )+3.5(X A -X B ) 2

Radio communication , Production of sound messages by a microphone in a rad...

Production of sound messages by a microphone in a radio station (studio). 1) Audio frequency generation. 2) Generation of r.f. carrier wave. 3) Modulation in a transmitter, b) 4

Internal resistance of circuit, Internal Resistance of Circuit: As ment...

Internal Resistance of Circuit: As mentioned earlier in the section on batteries, every source of electricity, such as a cell or generator has resistance to current flow called

Determination of analyte concentration, Determination of Analyte Concentrat...

Determination of Analyte Concentration: One of the most common applications of spectrophotometry is to determine the concentration of an analyte in a solution. There is a rela

Carnots theorem, Carnot's theorem (S. Carnot) The theorem which states...

Carnot's theorem (S. Carnot) The theorem which states that no engine operating among two temperatures can be more capable than a reversible engine.

Tunneling and tunneling applications, Q.   What is quantum mechanical "Tunn...

Q.   What is quantum mechanical "Tunneling"? Give one example. OR What do you mean by quantum mechanical tunneling? Show that the tunneling probability is given by the

Is there enough room in barge toehold this amount of coal, An open barge ha...

An open barge has the dimensions 22x40x12m. If the bargeis made out of 4.0-cm-thick steel plate on each of its four sides and its bottom, what mass of coal can the barge carry in f

Construction of neodymium-yttrium-aluminium-garnet laser, Describe the cons...

Describe the construction of Neodymium-Yttrium-Aluminium-Garnet Laser. Nd-YAG Laser The one of the illustration for solid state lasers is Neodymium-Yttrium-Aluminiu

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