uf vs volt which matters ?

[raincatsdogs]

I need some caps for a monitor. 1000 uf 16volt; and 680uf 25volt; the local shop only has 680 34volt; will it be ok if I use that ?

[tom66]

Re: uf vs volt which matters ?

No, it will not be OK unfortunately.

You need to get the capacitance (uF) as close as possible unless you know the power supply can work otherwise (which requires good understand of how it works.)

The voltage should be the same or higher.

However, another factor a lot of people overlook is that the replacements must be low impedance, or low ESR. Otherwise, they will either not work at all or fail in short order.

Digikey and Newark both ship to Canada and provide the caps you need.

[mariushm]

Re: uf vs volt which matters ?

If it's 34v, it's probably fake. You probably mean 35v.

You can go up in voltage a bit, so 35v would be OK
The uF value should be kept the same. In most cases, it's possible to use a capacitor with uF value a bit higher (the next standard value possible), but if you don't know what you're doing you shouldn't do it

Just to test if the capacitors are the problem with that monitor you may use 820uF/16-25v or 1200uF 16-25v capacitors instead of 1000uF 16v, and that 680uF/35v but if you want the monitor to run right and the fix to last, you need proper capacitors.

HOWEVER, with capacitors for monitors and power supplies, another property matters a lot and that one is not listed on them: the ESR. Monitors and power supplies need capacitors with LOW esr, which are generally a bit more expensive.

Your regular store, just like Radioshack in US, is unlikely to keep in stock low esr capacitors and if they do claim to have, they're low quality, no name (or some obscure brand) ones.

[raincatsdogs]

Re: uf vs volt which matters ?

No, it will not be OK unfortunately.

You need to get the capacitance (uF) as close as possible unless you know the power supply can work otherwise (which requires good understand of how it works.)

The voltage should be the same or higher.

However, another factor a lot of people overlook is that the replacements must be low impedance, or low ESR. Otherwise, they will either not work at all or fail in short order.

Digikey and Newark both ship to Canada and provide the caps you need.

Thank you. What would be a low impedance or esr level ?

[selldoor]

Re: uf vs volt which matters ?

The owner of this site sells those caps in low esr and ships to canada
https://www.badcaps.net/pages.php?vid=26 You will need to check the physical size will fit - you will have to do that whatever.

[raincatsdogs]

Re: uf vs volt which matters ?

If it's 34v, it's probably fake. You probably mean 35v.

You can go up in voltage a bit, so 35v would be OK
The uF value should be kept the same. In most cases, it's possible to use a capacitor with uF value a bit higher (the next standard value possible), but if you don't know what you're doing you shouldn't do it

Just to test if the capacitors are the problem with that monitor you may use 820uF/16-25v or 1200uF 16-25v capacitors instead of 1000uF 16v, and that 680uF/35v but if you want the monitor to run right and the fix to last, you need proper capacitors.

HOWEVER, with capacitors for monitors and power supplies, another property matters a lot and that one is not listed on them: the ESR. Monitors and power supplies need capacitors with LOW esr, which are generally a bit more expensive. I should mention the caps I'm replacing are Samxon.

Your regular store, just like Radioshack in US, is unlikely to keep in stock low esr capacitors and if they do claim to have, they're low quality, no name (or some obscure brand) ones.

Oh ok; good to know thank you.

I just phoned the local shop and they have 2: 1000uf 16 volt and 2: 680uf 35 volt; they are both manufactured by Luxon. He said there is no mention of an esr rating. How do I find the esr rating ?

[Pentium4]

Re: uf vs volt which matters ?

G-Luxon aren't that great. The ESR would probably be a little high on those, it's better to order caps from the mentioned sites or from Topcat and buy Japanese capacitors (Panasonic, Chemicon), it will last a lot longer