Re: [CAD_CAM_EDM_DRO] power suppy cap

Thomas Powell wrote:

>
> Are there any drawbacks to using a larger (farad) cap than
> the formula calls for?
>
> Thanks,
> Thomas

The only drawback is that it is bigger, and more dangerous!

However there are some advantages to going to a larger capacitor:

- obviously there is a bigger power reserve for hard accelerations

- Mariss 'formula' gives about 10% ripple. Doubling *2 (or quadrupling *4)
gives 1/2 (or 1/4) the ripple. Ripple inside the capacitor actually
generates heat which is very bad for capacitor life ( every 10°C increase
in capacitor temperature halves its life).

Therefore, a bigger size means less heating and longer cap life.

On a related note, I suggest everyone have their power supply fan impinge
directly on the capacitor as much as possible, after which the fan blast
should then cool the driver heatsinks. This maximizes the lifespan of the
capacitors.

cheers
Doug Fortune
http://www.cncKITS.com monster 68,000uF 80V/100Vpk 105°C caps now in stock!


























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