Capacitors in PSU are dangerous?

"Regal" wrote in message
...
I read on some website that the capacitors in a PC's PSU can hold a
charge for long after they have been switched off and that the
charge could be fatal.

Is this really so? Surely that is exaggerating?

Isn't that CRT monitors not PC PCUs?
--

Niel Humphreys

Niel Humphreys wrote:
"Regal" wrote in message
...

I read on some website that the capacitors in a PC's PSU can hold a
charge for long after they have been switched off and that the
charge could be fatal.

Is this really so? Surely that is exaggerating?

Isn't that CRT monitors not PC PCUs?

Both. They're used in the AC-DC transformer.

--
Paul

Paul Hill wrote:
Niel Humphreys wrote:

"Regal" wrote in message
...

I read on some website that the capacitors in a PC's PSU can hold a
charge for long after they have been switched off and that the
charge could be fatal.

Is this really so? Surely that is exaggerating?


Isn't that CRT monitors not PC PCUs?


Both. They're used in the AC-DC transformer.


And what are the voltages and capacitances?

Some switched mode power supplies start by rectifying the mains voltage to
350+volts dc and storing this on a capacitor.That is enough to kill you in
certain circumstances.All capacitors from main powered equipment should be
treated with respect.
Ken Reynolds

"Regal" wrote in message
...
I read on some website that the capacitors in a PC's PSU can hold a
charge for long after they have been switched off and that the
charge could be fatal.

Is this really so? Surely that is exaggerating?
No they are serious, I had the Unfortunate experience not too long ago of
puncturing one on accident. Nasty little shock, let me tell ya. Some nice
electrical burns as well.

Chris Stolworthy wrote:
"Regal" wrote in message

I read on some website that the capacitors in a PC's PSU can
hold a charge for long after they have been switched off and
that the charge could be fatal.

Is this really so? Surely that is exaggerating?

No they are serious, I had the Unfortunate experience not too
long ago of puncturing one on accident. Nasty little shock,
let me tell ya. Some nice electrical burns as well.

We used to take a 200V 0.1 uF capacitor and stick the leads into a
110 V a.c. socket. Everyone knows you can't charge a cap from an
a.c. supply, right? Then hand it to someone to hold. Carefully.

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"CBFalconer" wrote in message
...
Chris Stolworthy wrote:
"Regal" wrote in message

I read on some website that the capacitors in a PC's PSU can
hold a charge for long after they have been switched off and
that the charge could be fatal.

Is this really so? Surely that is exaggerating?

No they are serious, I had the Unfortunate experience not too
long ago of puncturing one on accident. Nasty little shock,
let me tell ya. Some nice electrical burns as well.

We used to take a 200V 0.1 uF capacitor and stick the leads into a
110 V a.c. socket. Everyone knows you can't charge a cap from an
a.c. supply, right? Then hand it to someone to hold. Carefully.


Presumably it depends when you remove it from the AC supply on how
much of a shock you get. If you are lucky you might not get
any shock at all. Unlucky if you get the full 110V. Or 240 in the UK.
Who uses 110V?


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On Sat, 17 Apr 2004 23:38:57 +0100, "half_pint"
wrote:

Presumably it depends when you remove it from the AC supply on
how much of a shock you get. If you are lucky you might not
get any shock at all. Unlucky if you get the full 110V.
Or 240 in the UK. Who uses 110V?

All Europe use 230V today. UK adapted from 240V to 230V
and the other countries from 220V to 230 volts.

Ken wrote:

All Europe use 230V today. UK adapted from 240V to 230V
and the other countries from 220V to 230 volts.

Nobody ACTUALLY changed their voltage, at least initially.

UK voltage used to be 240V nominal, tolerance -6%, +6%. Actual voltage
was typically 240V.

After the change UK voltage was 230V nominal, tolerance -6% +10%. Actual
voltage was typically 240V.

Best wishes,
--
Michael Salem

"CBFalconer" wrote in message
...
Chris Stolworthy wrote:
"Regal" wrote in message

I read on some website that the capacitors in a PC's PSU can
hold a charge for long after they have been switched off and
that the charge could be fatal.

Is this really so? Surely that is exaggerating?

No they are serious, I had the Unfortunate experience not too
long ago of puncturing one on accident. Nasty little shock,
let me tell ya. Some nice electrical burns as well.

We used to take a 200V 0.1 uF capacitor and stick the leads into a
110 V a.c. socket. Everyone knows you can't charge a cap from an
a.c. supply, right? Then hand it to someone to hold. Carefully.

Thats quite a good laugh unless you wnd up on a manslaughter charge.


--
A: Because it fouls the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing on usenet and in e-mail?