capacitor question

[robotgangsta]

what voltage would a 10,000uF 25V Radial Electrolytic Capacitor build up to dont know if question is right but would it be good for the coil gun

 

[Styx]

errr build up to?
its a 25V capacitor, exceed that rating and the dialetric will break-over

capacitors due have memory effect, but that is like 15V for a 600V capcacitor.

dont quite follow what you are asking?

 

[mstechca]

what voltage would a 10,000uF 25V Radial Electrolytic Capacitor build up to...

depends on what voltage is applied to it.

If it is under 25V, then the capacitor will go up to that voltage. If it is over 25V, then I think that the capacitor willgo up to 25V, and possibly be damaged.

the uF means microfarad. It is a rating that contibutes to the time it takes to charge a capacitor. The full formula is resistance * capacitance.

25V is just a warning sign letting you know that you should give it less than 25V.

 

[robotgangsta]

if i put 2 in a curcuit with a 9v battery what would the voltage build up to

 

[Styx]

err no. IF the only voltage avail in the cct is 9V, the maximum voltage those caps will ever reach is 9V (well just less)

what are you trying to do. That might help if we knew

 

[robotgangsta]

just trying to figure out what the best caps to use for a coil gun are

 

[Someone Electro]

Well i used six 10 000 uF 63V caps.There are 3 parallel pairs of 2 in serial.

You need an higher voltage. 60V was not enugh in my case.The caps codnt discharge fast enugh.So i had to put 2 in serial to get an max rating of 126 V i charge then to about 100-110V.

Also an a lot smaller caps is beter then an single huge cap.Becose a lot of parellel smaller caps will have an way lover resistance then on big cap.And so can discharge faster.

Those 1F super caps (aka gold caps) can hold a LLOOTT of charge but they cant put out high curents.1A is probobly the most you can draw form it.

You shod search vasirus component stores.I got my caps for $3.50 each at IC elektronika.You will probobly find them even cheaper since this is an small suplyer.

And i got the SCRs at HTE for about $1.50 each.

I order all of this stuff online.So i have to pay some shiping fees.

 

[zhi_yi]

hi there, i am sorry if this is out of topic.. i have a question about the capacitor..

sometime ago, i try to charge the capacitor with maximum voltage 25V (1000uF - 25V), i charged it more than 25V, it's about 26-27 V, but i see that it's not burned out the capacitor, why??

thank you

 

[Nigel Goodwin]

sometime ago, i try to charge the capacitor with maximum voltage 25V (1000uF - 25V), i charged it more than 25V, it's about 26-27 V, but i see that it's not burned out the capacitor, why??

The death of the capacitor isn't a precision event!, it's simply guaranteed (hopefully?) to be able to withstand it's rated voltage. Any more than that is exceeding it's design specification, and it may well fail - but the exact point will vary from unit to unit, and probably on temperature as well?.

However, you shouldn't exceed it's rated voltage, modern electrolytic capacitors are particularly crap! - they won't usually withstand much extra voltage, and won't generally last very long anyway!.