Capacitor voltage rating - Electronic Circuits Projects Diagrams Free

skyymanz · 7th July 2005, 01:52 AM

Hi all,

anyone know wat will be a save range to chose for a capacitor voltage rating? i want to filter a ripple signal from a 48V output rectifier. the capacitor i use should have what voltage rating? thanks!

cheers!
Skyy

instruite · 7th July 2005, 02:27 AM

I assume by 48V you mean RMS value (i.e. constant DC value)
so the Peak voltage of your signal will be 48*(2^0.5) = 68V
and we normally keep safety margin of 1.5
So you requirment will be 68*1.5 = 102V

So I will recommend you to use a capacitor with atleast 100V rating

The following link might be useful for you
http://www.electronics-tutorials.com...wer-supply.htm

shamikrudra · 7th July 2005, 03:14 AM

Quote:

Originally Posted by skyymanz

Hi all,

anyone know wat will be a save range to chose for a capacitor voltage rating? i want to filter a ripple signal from a 48V output rectifier. the capacitor i use should have what voltage rating? thanks!

cheers!
Skyy

u can use 63 V or for more 100V for safty
but consider the space 100V will be bigger in size

skyymanz · 7th July 2005, 03:21 AM

Hi instruite

Thanks for the reply!

mstechca · 7th July 2005, 10:08 PM

personally, I double the applications requirement just incase AC voltage is used. so 48 * 2 = 96. capacitors with higher numbers are much better.

Laplink · 10th July 2005, 06:36 AM

Greetings,
A capacitor with a working voltage of at least 48 volts will work. A 50Volt capacitor will work but as with anything pushed to it's maximum limit, it's life will be limited. A manufacturer may use a 63 Volt capacitor to save their $0.02c worth.
I am with Mstechca, I like to double the rating, so 100 Volts it is!
Also if it will be mounted near anything warm like a heatsink, large resistor or such, use a high temperature capacitor (105 degrees celcius) for longer life. I guess you are rectifing 120 Hz and not high frequency so ESR is of no consideration?

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7th July 2005, 01:52 AM	(permalink)
skyymanz	Capacitor voltage rating Hi all, anyone know wat will be a save range to chose for a capacitor voltage rating? i want to filter a ripple signal from a 48V output rectifier. the capacitor i use should have what voltage rating? thanks! cheers! Skyy

7th July 2005, 02:27 AM	(permalink)
instruite	I assume by 48V you mean RMS value (i.e. constant DC value) so the Peak voltage of your signal will be 48(2^0.5) = 68V and we normally keep safety margin of 1.5 So you requirment will be 681.5 = 102V So I will recommend you to use a capacitor with atleast 100V rating The following link might be useful for you http://www.electronics-tutorials.com...wer-supply.htm __________________ Instruite http://www.icesociety.org ===================== Ideas that work, Concepts that sell. =====================

7th July 2005, 03:21 AM	(permalink)
skyymanz	Hi instruite Thanks for the reply!

7th July 2005, 10:08 PM	(permalink)
mstechca	personally, I double the applications requirement just incase AC voltage is used. so 48 * 2 = 96. capacitors with higher numbers are much better. __________________ -=: The best low-priced components to troubleshoot with are the speaker and the LED :=-

10th July 2005, 06:36 AM	(permalink)
Laplink	Greetings, A capacitor with a working voltage of at least 48 volts will work. A 50Volt capacitor will work but as with anything pushed to it's maximum limit, it's life will be limited. A manufacturer may use a 63 Volt capacitor to save their $0.02c worth. I am with Mstechca, I like to double the rating, so 100 Volts it is! Also if it will be mounted near anything warm like a heatsink, large resistor or such, use a high temperature capacitor (105 degrees celcius) for longer life. I guess you are rectifing 120 Hz and not high frequency so ESR is of no consideration?