Low voltage and high voltage caps are same size?

[grizedale]

This datasheet states that its 250VDC and 450VDC 470n capacitors are almost exactly the same size.................surely this cannot be right.?

ECWF2474 = 250V, 470n
ECWF2W474 = 450V, 470n

datasheet =
https://panasonic.com/industrial/includes/pdf/ABD0000CE47.pdf

 

[Raza]

Hi grizedale,
Why you doubt for the working voltage can not be low (250V) and high (450V) ?. As the manufacturer says and defined the different identification for both categories. You are hesitating to accept on the voltage for same size?.
It is possible, I have used many like that, rather some time the High voltage size was smaller that the lower voltage one.

 

[grizedale]

higher voltage caps are usually bigger.

The datasheet does say that the higher voltage ones are for filtering, and the lower voltage ones for SMPS/Pulse currents.

So one would guess that that is the reason.

Its a shame the ripple rating for each cap is not stated.

 

[vimalkhanna]

The two voltages are not very different as the double metallized polyester sheet used for winding the capacitors is 600VDC rated .
The same poly. sheet is used for winding the 250VDC //350VDC /400VDC /450VDC as well as 600VDC .
The burn in wave which clears the spacing is different (wider) for the higher voltages like 600V and narrower for the 250V
There is another aspect ..The box case used for encapsulation could be the same as this reduces the overall investment costs of the manufacturer .

 

[Raza]

Hi,
Some times Polyester Double sided film is used to wind the capacitors but to increase the working voltage the Dielectric is changed polyester to Polypropylene. The Polypropylene is best for Pulsed applications and have better service in AC applications too. This is about the mini box capacitors.
And I will say that there no END to technology.