how i know what type of capacitor

What is the maximum working voltage in your system? How accurate do you need the value to be? Is this a power supply type application, or something else (please explain your setup).

regards, John

thanks for your cooperation..;p my title of my project is 'automatic power factor correction'. so i used this capacitor in my control circuit. i have current input circuit by using current transformer to sense a current in my circuit.

Sorry, but still don't know enough - what is the maximum working voltage?

BTW - the colour really doesn't matter - you can paint them white after testing if you must !

Because he's specified a colour, I'd guess that he's trying to identify an actual part that he has already used.

Am I right missalina?

If you are trying to find out what the capacitance of the part is an RC meter would help a lot. But it's not going to tell you the max voltage. Why can't you get a part that is labeled?

If you are trying to get help specifying a part we are going to need a lot more information.

Go to website www.Kemet.com and you will have the knowledge base which also deals with capacitor selection. Life will be very easy as far as selection goes.

Hello are you doing powerfactor correction? if so first you have to find out the leading KVAR to be supplied by the capacitor bank to get your desired power factor. from that you can find out no of capacitor needed and its rating.

shinerajcet@gmail.com

You can get all these thing and more when you go to www.Kemet.com for capacitor selection guide. I have been able to get the full range of querry I had connected with the capacitor size, number, power and losses and more. This is very good and handy website with knowledge base, frequently asked question and then selection of size type and numbers to make use in your project

Metalised polyester or PP capacitors probably will do, but you have to define your waveform: a) pure AC b) pure DC (small ripple) c1) DC with superimposed AC, no (or very small) voltage reversal c2) idem, with voltage reversal... and of course your frequency.

Hi missalina,

For the large values you show, they will probably need to be electrolytic capacitors. They are normally polarized, but you can connect them back to back (in series). For example, connect both negative ends together and use the positive ends for your circuit. Both capacitors must be rated at the voltage across the two. Nonpolarized are sometimes available.

regards,

-S