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Dave Gray
07-22-2016, 09:30 PM
My Samsung TV blew a cap in the power supply. Funny things is, this TV has worked fine until I hooked up a new Tivo using HDMI. The cap is is a 2200 uF 10v cap. Do you think I would be okay using a 20V cap until I get the right component? I guess the risk is burning up the LDC TV.

Thanks,

David G
07-22-2016, 10:32 PM
I'm no techie. But if it were me... I'd go with a nice knit wool cap. Maybe one of the experts will come along and back me up?

Old Dryfoot
07-22-2016, 11:36 PM
I put new caps of a higher voltage in my Onkyo receiver. So far, so good.

Syed
07-23-2016, 01:49 AM
IMO, should be safe with a higher voltage rating capacitor.

P.I. Stazzer-Newt
07-23-2016, 02:44 AM
So long as it goes in the right way round.....

epoxyboy
07-23-2016, 04:07 AM
Samsung, like any electronics manufacturer (I work for one in an engineering role) will have designed in the cheapest component that does the job, with some reasonable margin to achieve the design lifetime.
Fitting a cap with a higher voltage rating will have a greater margin, and wont cause any problem at all, the capacitance is the important value here.
The higher voltage capacitors are often physically larger, but if it fits, there is absolutely no point whatsoever in replacing it with the "correct" part later on. Just be aware that if it is an electrolytic cap (with a 10v rating, I'm assuming it is) they are polarity sensitive, and will have a stripe on the plastic sheath lining up with one pin. The replacement MUST (I feel like Norman) go in the same way around, or will rupture and ooze corrosive goo all over the innards of your tv.

Pete

Bob Adams
07-23-2016, 06:39 AM
Should be no harm at all in using a higher voltage rating.

Durnik
07-23-2016, 08:00 AM
Pete called it. there is absolutely no harm in using a cap with a higher voltage rating as that is simply the maximum safe voltage the cap can withstand. you might guess - and you would be correct - that in operation a cap usually works at less than its max voltage.

enjoy
bobby

David G
07-23-2016, 08:13 AM
Samsung, like any electronics manufacturer (I work for one in an engineering role) will have designed in the cheapest component that does the job, with some reasonable margin to achieve the design lifetime.
Fitting a cap with a higher voltage rating will have a greater margin, and wont cause any problem at all, the capacitance is the important value here.
The higher voltage capacitors are often physically larger, but if it fits, there is absolutely no point whatsoever in replacing it with the "correct" part later on. Just be aware that if it is an electrolytic cap (with a 10v rating, I'm assuming it is) they are polarity sensitive, and will have a stripe on the plastic sheath lining up with one pin. The replacement MUST (I feel like Norman) go in the same way around, or will rupture and ooze corrosive goo all over the innards of your tv.

Pete

I'm SO disappointed, Pete. I thought YOU of all people, being from the land of merino wool, would back me up <G>

Dave Gray
07-23-2016, 11:13 AM
Thanks everyone. I replaced the cap. There were more blown parts so when I plugged the TV in I got a tripped circuit breaker (again) and sparks, fire cracker noises, and so on. In other words it didn't pass the smoke test. A closer examination of the board revealed some potential areas that were problematic, including a circular item, I have no idea what it is but it is circular, on two legs, and the black plastic casing has the top blown away. Not worth messing around with any more.

David G
07-23-2016, 02:44 PM
Shoulda prolly gone with the merino wool. You can always tell an Orygonian... you just kain't tell 'em much. <G>

PhaseLockedLoop
07-23-2016, 03:26 PM
Thanks everyone. I replaced the cap. There were more blown parts so when I plugged the TV in I got a tripped circuit breaker (again) and sparks, fire cracker noises, and so on. In other words it didn't pass the smoke test. A closer examination of the board revealed some potential areas that were problematic, including a circular item, I have no idea what it is but it is circular, on two legs, and the black plastic casing has the top blown away. Not worth messing around with any more.

Didn't the TV say DO NOT OPEN: NO USER SERVICABLE PARTS INSIDE? Huh? I bet you're one of those people who clip the labels off sofa cushons that say not to clip them off.

...hmm. Blown full-wave rectifier?

Dave Gray
07-23-2016, 04:20 PM
Didn't the TV say DO NOT OPEN: NO USER SERVICABLE PARTS INSIDE? Huh? I bet you're one of those people who clip the labels off sofa cushons that say not to clip them off.

...hmm. Blown full-wave rectifier?

Rebel and bad to the bone, that's me.

I'm not sure the capacitor I replaced was really bad. The component that blew is not one I have seen before but it has been a long time since I tinkered with breadboards and circuits.

willmarsh3
07-23-2016, 08:26 PM
How old is this TV

Captain Intrepid
07-24-2016, 12:53 AM
There's a good chance you should be able to source a new power supply if you look around enough.