1000 uf Caps :)

[best4less]

You have to love 1000uf caps
They are a real easy earner as Arthur Daley would say from Minder

I have changed over 25 of the little buggers today (4 of them out of my own equipment lol )

I wonder why they are so useless in the secondary side of power supply circuits ???

[Godzilla]

Shhh, while they fail, you party mate. LOL

I must have saved myself and freinds a small fortune changing caps and not throwing out equipment lately.

What is it, poor quality cheaply built or minimal voltage ratings to save costs?

[iwacelect]

You have to love 1000uf caps
They are a real easy earner as Arthur Daley would say from Minder

I have changed over 25 of the little buggers today (4 of them out of my own equipment lol )

I wonder why they are so useless in the secondary side of power supply circuits ???

THANK GOD!!!!

those 25v, 35v, 63v buggers are great stuff, just keeps gasping and dieing i say, also make sure you replace with 85deg caps and it'll bounce but at least more than 3 months down the track....LOL

[beer4life]

You have to love 1000uf caps
They are a real easy earner as Arthur Daley would say from Minder

I have changed over 25 of the little buggers today (4 of them out of my own equipment lol )

I wonder why they are so useless in the secondary side of power supply circuits ???

G'Day,
They're a brute force way of ripple smoothing and often under rated for economy.
Surely you're not that young that you do not remember the 300 V power supplies with 16/8 ufd caps and a smoothing choke or speaker coil. Admittedly they often broke down, but were handling far higher ripple voltage.
Arrhh, those were the days.
Kindest Regards, " The Druid "...

[BCNZ]

Heat is the killer of caps. It dries the dielectric out and they lose their capacitance or cease to function completely.

Most equipment uses 85°C caps because they are cheap to manufacture.

If you want something to last, or you are building your own gear, go for the 105°C caps.

I've also seen some dodgy sounding names on these little beasties that lead me to believe they are made in china.

Elna used to be a good brand but rarely see them these days. I think there was a brand called "Nichicon" which is obviously Japanese, but they too are few and far between.

Caps on the secondary side of power supplies have a lot of ripple (AC) to deal with, which does take its toll on them. A good L-R filter can help remove some of this. Some of the older people here who have worked with valves will know only too well the filtering in valve radios for example.

LOL... sorry Druid, didn't read your post first

[gordon_s1942]

I am waiting for a friendly repair man to return after the xmas break to both obtain and fit a 330 uF 25V 105C cap I THINK has gone, (lovely domed top) from the power supply of a Medion LCD monitor.
There is no one locally who carries components anymore except for him and the DS/JC stores 50 ks away only carry bags of 10 assorted and of 85 C according to their adds.
I noted that the circuit board between this cap and possibly a transformer of sorts is very much browner indicating it gets fairly hot so whether it has taken out anything else as the underside of the board has lots of them tiny nasty SMD's all over it is unknown untill its turned on again.
I bought the monitor 3 years ago so it owes me nothing but if I can get it fixed, all the better.
I dont really want to fiddle replacing the cap, desoldering is not one of my strong points.
I have 2 Humaxs that suffered the dead cap problem but luckily nothing else went when they did.

[Uncle Fester]

You have to love 1000uf caps
I have changed over 25 of the little buggers today (4 of them out of my own equipment lol )

That's nothing I used 100 1000µF capacitors today
...but old school as I am, I decided to use one of these instead




I recommend two of them in the power supply if you want to build yourself a nice sounding class A amplifier.

[best4less]

Well i sure would like to see one of them go bang LOL

[LeroyPatrol]

Well i sure would like to see one of them go bang LOL

a fellow had a small electo go bang at work many years ago and hit and blinded him in one eye. Hate to see what this one would do

Leroy

[vbthanks]

Back in the old CB radio days i built my first power supply with the smoothing cap inserted the wrong way around - switched it on via the switch on the front panel and boom ! Paper and oil on the ceiling, floor, me ! Mum came running to the bedroom (I called it my workshop) and banned from from any further electronics inside the house.

After that episode, whenerever I built power supplies, i'd hide under the table and swich on from the mains !

[BCNZ]

As an apprentice I was once made to "catch the cap".

One of the other guys in the workshop had a 10uF 400V cap which he would plug into the mains, charge up then throw to you from across the other side of the workshop. You couldn't see what it was before he threw it and of course the instinct is to grab whatever is thrown at you.

It had big terminals on the end, and when you caught it, you couldn't help but touch the terminals at some point.

It's not a pleasant experience.

[beer4life]

As an apprentice I was once made to "catch the cap".

One of the other guys in the workshop had a 10uF 400V cap which he would plug into the mains, charge up then throw to you from across the other side of the workshop. You couldn't see what it was before he threw it and of course the instinct is to grab whatever is thrown at you.

It had big terminals on the end, and when you caught it, you couldn't help but touch the terminals at some point.

It's not a pleasant experience.

G'Day Cobber,
This story seems to have got embellished over the years.
Did you have DC mains there? It would be hard to determine the charge as it was disconnected from AC.
The other thing, if an electro, wonder it didn't explode if AC mains.

Kindest Regards, " The Druid ".
PS: Come to think of it, was there ever such a thing as a 10 Ufd / 400 Volt Capacitor?
Possibly " motor start ", but would they have pigtails?

[Uncle Fester]

I am no hero and a terrible catch. I always had the instinct to duck or run if somebody throws something at me.
I can dodge flying spanners too

Well i sure would like to see one of them go bang LOL

(un)fortunately it has a safety valve to spoil the fun and it will trip every circuit breaker if you connect it to mains unless it can handle several kA in which case the connectors will just melt.

[WH20]

As an apprentice I was once made to "catch the cap".

One of the other guys in the workshop had a 10uF 400V cap which he would plug into the mains, charge up then throw to you from across the other side of the workshop. You couldn't see what it was before he threw it and of course the instinct is to grab whatever is thrown at you.

It had big terminals on the end, and when you caught it, you couldn't help but touch the terminals at some point.

It's not a pleasant experience.

I remember that when i was at tech,i was the one throwing them.
You just brought back some good memories.

[porkop]

I wonder why they are so useless in the secondary side of power supply circuits ???

I have about 100,000 uF in my PS, it growns a bit with the inrush current when turned on...maybe why I leave it on all the time

[BCNZ]

PS: Come to think of it, was there ever such a thing as a 10 Ufd / 400 Volt Capacitor?
Possibly " motor start ", but would they have pigtails?

Yes, the cap was very real. I still have the vision in my head of it sitting plugged into the hotpoint charging up. This was when I'd come out of my time and it was my turn to throw it at our unsuspecting apprentice.
It may have been a motor start cap, I don't remember - but it had terminals on the end, not pigtails, and was quite happy sitting for 10 minutes plugged straight into the power.

[voltare1]

i found that with lcd's and main boards, if you dont have an exact match go higher. the ones ive fixed had 1000uf 6.3v i believe, replaced with 1500uf/16v and they run well.

[PostScriptum]

Have a read of

I replaced hundreds of motherboards and power supplies in 2003-2005 thanks to a 'industrial espionage foul-up' or so I was told. Nichicon was the name I saw a lot but hopefully they would have fixed their problem since about 2001 on as far as I know. Watch out for old stock though!

EDIT:
"As of May 2005[update],[5] some evidence shows that the failing Nichicon capacitors on the iMac, Intel, and Dell boards are due to a different problem (capacitors overfilled with electrolyte) than the one primarily being discussed on this article (faulty electrolyte formula)."

[best4less]

That's a pisser about the guy who stole the recipe "if that's what you want to call it" for the caps and gets it wrong

I really want to thank him LOL well my pocket does

[z80]

Apparently car ECU's are prone to cap failure and a lot can easily be repaired.

Look for car ECU's in the 2002-2006 vintage...