Use a higher voltage cap?

[bw1]

Recently had a monitor with bad caps in power supply.

It needed a mixture of 680uf/25v and 470uf/25v.
I had the 680uf/25v, but only had 470uf/35v available, and ended up replacing the three 470uf/25's with 470/35's.

Everything seems to work just fine, but what is the risk, if any, in doing this?

Obviously, one risk would be that it just wouldn't work. So, I should re-phrase the question:

If everything seems to work, what risk, if any, is there in doing this? (Assuming you would always use the same or slightly higher voltage cap)

[retiredcaps]

Re: Use a higher voltage cap?

You can go up in voltage with no issues. PCBONEZ explains it more here

https://www.badcaps.net/forum/showpo...30&postcount=7

[bw1]

Re: Use a higher voltage cap?

That brings up another point in the article - size. Not a good idea to replace the smaller one with the bigger one, even though the cap/volt ratings are the same?

(Picture)

[retiredcaps]

Re: Use a higher voltage cap?

I noticed that Pansonic's new FR series is equivalent to or BETTER the FM series, but sometimes in smaller dimensions for the same uF and voltage cap.

[bw1]

Re: Use a higher voltage cap?

Well in the example above, all I've got is the smaller one, and the bigger one is the one that was original. What's the best way to tell what to replace this one with? Normally, as long as the shape is pretty much the same and values on the side match, I just go with it, but when there's an obvious size difference, I'm less likely to do so.

As far as I can tell, the [1000uF 25v 12.5mm ZLG Series] (Rubycon stock link @ badcaps) is what I would really need.

Should I spend the extra and order that (nothing else needed at the moment, so would be a bigger order for a couple caps) or use the smaller one?

[retiredcaps]

Re: Use a higher voltage cap?

Well in the example above, all I've got is the smaller one,

Before you posted this, I re-read and edited my reply above.

The only reason go from Rubycon PX to ZLG is because the electrical application require a low ESR cap like ZLG. PX is not a low ESR cap regardless of it is physical size. See

https://www.badcaps.net/forum/showthread.php?t=2280

So if these caps are part of your power board lcd monitor (i.e. an SMPS application), then you should get the ZLG since it is low ESR.

[PlainBill]

Re: Use a higher voltage cap?

Well in the example above, all I've got is the smaller one, and the bigger one is the one that was original. What's the best way to tell what to replace this one with? Normally, as long as the shape is pretty much the same and values on the side match, I just go with it, but when there's an obvious size difference, I'm less likely to do so.

As far as I can tell, the [1000uF 25v 12.5mm ZLG Series] (Rubycon stock link @ badcaps) is what I would really need.

Should I spend the extra and order that (nothing else needed at the moment, so would be a bigger order for a couple caps) or use the smaller one?

The parameters I use (and my target values) are capacitance (exact match unless several are in parallel, then try to achieve the same total capacitance), voltage (exact match, higher if necessary), dimensions (must fit in available space), ESR (lower is better), life expectancy (higher is better). If the information is available, I will use the ESR of the original as a 'not greater than' target.

If the original was a 2200uF 25V and I have a 2200uF, 35V Panasonic FC on hand I'll use it if it fits. If I'd have to wedge it in, I'll get a proper replacement rather than turn out something sloppy.

PlainBill

[bw1]

Re: Use a higher voltage cap?

Well looking again I've got Samxon 1000uf/25v GT's, Rubycon 1000uf/25v PX's. The one I mentioned I would need to order is the ZLG series.

Are you saying no PX's should go anywhere in a power supply board? Also, what about Samxon GT or GC.

I know I've seen reference charts of ESR values for caps floating around here, but what about a reference for where each type is appropriate? That's what I'm never positive on.

Also, I suppose, are there actual risks to using a higher ESR cap? Obviously, I'm the same way - I want the results the same or better as the original. I'm more curious than anything.

[bw1]

Re: Use a higher voltage cap?

I guess one other question is, and I'm sure there would be inconsistencies here on occasion, but is it safe to say that most/all of the caps sold here are ok to use in a monitor power supply?

[PlainBill]

Re: Use a higher voltage cap?

Well looking again I've got Samxon 1000uf/25v GT's, Rubycon 1000uf/25v PX's. The one I mentioned I would need to order is the ZLG series.

Are you saying no PX's should go anywhere in a power supply board? Also, what about Samxon GT or GC.

I know I've seen reference charts of ESR values for caps floating around here, but what about a reference for where each type is appropriate? That's what I'm never positive on.

Also, I suppose, are there actual risks to using a higher ESR cap? Obviously, I'm the same way - I want the results the same or better as the original. I'm more curious than anything.

Note the link in my signature (above) - 'Which Caps should I buy?'. It takes you to a list of suitable series of caps in the FAQ. If they aren't on that list, don't use them in the power supply secondary. Note that you can recap most 15 - 23" monitors for under $10.00 including shipping.

PlainBill

[retiredcaps]

Re: Use a higher voltage cap?

PCBONEZ talks about ESR and what it is supposed to do

https://www.badcaps.net/forum/showpo...51&postcount=7