Hi,

I'm going to do some experimentation on high voltage equipments
( transformers, power supplies, capacitor banks, lasers , etc.. ).

Does anyone know where I could find some safety guidelines or notes
about working with this dangerous stuff ?

( I wouldn't like to die because of a spark jump and make my wife a
widow... )

Thanks

Stef

wrote:
Hi,

I'm going to do some experimentation on high voltage equipments
( transformers, power supplies, capacitor banks, lasers , etc.. ).

Does anyone know where I could find some safety guidelines or notes
about working with this dangerous stuff ?

( I wouldn't like to die because of a spark jump and make my wife a
widow... )

Thanks

Stef

Oh, brother. Do her a favour and take up welding instead.

Cheers

Phil Hobbs

On Mon, 04 May 2009 13:04:40 -0400, Phil Hobbs
wrote:

wrote:
Hi,

I'm going to do some experimentation on high voltage equipments
( transformers, power supplies, capacitor banks, lasers , etc.. ).

Does anyone know where I could find some safety guidelines or notes
about working with this dangerous stuff ?

( I wouldn't like to die because of a spark jump and make my wife a
widow... )

Thanks

Stef

Oh, brother. Do her a favour and take up welding instead.

Cheers

Phil Hobbs

Wonder what his wife's take on this experiment is? Maybe she's all for
it? g

http://video.google.com/videoplay?do...01008541895226

On May 4, 5:59*pm, "Charles" wrote:
http://video.google.com/videoplay?do...01008541895226

Two deathly dangers - one from actual electrical shock, one from
impaling yourself on something sharp when you jump from the shock and
bleed to death

On 05/04/2009 04:52 AM, sent:
Hi,

I'm going to do some experimentation on high voltage equipments
( transformers, power supplies, capacitor banks, lasers , etc.. ).

Does anyone know where I could find some safety guidelines or notes
about working with this dangerous stuff ?

( I wouldn't like to die because of a spark jump and make my wife a
widow... )

Thanks

Stef

Hello Stef:

Please define the levels of high voltage you are referring to.

Laser safety is also an entirely different subject. What type & class
laser?

Pete
--
1PW @?6A62?FEH9E=6o2@=]4@ [r4o7t]

hr(bob) wrote:
On May 4, 5:59 pm, "Charles" wrote:
http://video.google.com/videoplay?do...01008541895226

Two deathly dangers - one from actual electrical shock, one from
impaling yourself on something sharp when you jump from the shock and
bleed to death

Heh. The second point is the one that tends to catch telco tech's when
the phone rings while they're working on the MDF. ;^)

--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------

Bob Larter wrote:

hr(bob) wrote:
On May 4, 5:59 pm, "Charles" wrote:
http://video.google.com/videoplay?do...01008541895226

Two deathly dangers - one from actual electrical shock, one from
impaling yourself on something sharp when you jump from the shock and
bleed to death

Heh. The second point is the one that tends to catch telco tech's when
the phone rings while they're working on the MDF. ;^)

If the 'phone rings while you are doing the ironing, you can get a badly
burned ear.

--
~ Adrian Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

Two deathly dangers - one from actual electrical shock, one from
impaling yourself on something sharp when you jump from the shock and
bleed to death

A good reason to find another line of work. Just remember, a live circuit
looks exactly like a dead circuit. Also HV caps can hold a charge enough to
bang you too. If you learned on tube gear, then maybe you know enough, but
LV circuits just don't have the urgency required to heighten your paranoia
for survivability. You essentially have to develop a checklist in your head
for each time you put a hand (only one) into the dead equipment and never
fail. Instructions are normally in the Service Manual of all HV equipment.

JB wrote:
Two deathly dangers - one from actual electrical shock, one from
impaling yourself on something sharp when you jump from the shock and
bleed to death

My classic screwup was a time, as a smartarse teenager, when I was
working on a 28" display monitor, & /thought/ I'd discharged the CRT
correctly via the ultor cap. I lifted the ultor cap to unhook it, & a
giant spark bit me. The shock threw me clear across the room, & I just
missed slamming into a bench.

A good reason to find another line of work. Just remember, a live circuit
looks exactly like a dead circuit. Also HV caps can hold a charge enough to
bang you too. If you learned on tube gear, then maybe you know enough, but
LV circuits just don't have the urgency required to heighten your paranoia
for survivability. You essentially have to develop a checklist in your head
for each time you put a hand (only one) into the dead equipment and never
fail. Instructions are normally in the Service Manual of all HV equipment.

All good advice.


--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------

Bob Larter wrote:

My classic screwup was a time, as a smartarse teenager, when I was
working on a 28" display monitor, & /thought/ I'd discharged the CRT
correctly via the ultor cap. I lifted the ultor cap to unhook it, & a
giant spark bit me. The shock threw me clear across the room, & I just
missed slamming into a bench.


This explains a lot! ;-)


--
You can't have a sense of humor, if you have no sense!

Michael A. Terrell wrote:
Bob Larter wrote:
My classic screwup was a time, as a smartarse teenager, when I was
working on a 28" display monitor, & /thought/ I'd discharged the CRT
correctly via the ultor cap. I lifted the ultor cap to unhook it, & a
giant spark bit me. The shock threw me clear across the room, & I just
missed slamming into a bench.


This explains a lot! ;-)

I suppose you've never zapped yourself? ;^)

--
W
. | ,. w , "Some people are alive only because
\|/ \|/ it is illegal to kill them." Perna condita delenda est
---^----^---------------------------------------------------------------

Bob Larter wrote:

Michael A. Terrell wrote:
Bob Larter wrote:
My classic screwup was a time, as a smartarse teenager, when I was
working on a 28" display monitor, & /thought/ I'd discharged the CRT
correctly via the ultor cap. I lifted the ultor cap to unhook it, & a
giant spark bit me. The shock threw me clear across the room, & I just
missed slamming into a bench.


This explains a lot! ;-)

I suppose you've never zapped yourself? ;^)


Not like that. The HV I worked with wasn't measured in micro amps.
It was inside the TV transmitter. One touch, and you're dead. Think
what a HV DC power supply for three 65 KW Klystrons would do to you,
when the power supply put out a continuous 195 KW. In fact, you
wouldn't even need to touch it.


--
You can't have a sense of humor, if you have no sense!

"Michael A. Terrell" wrote in message
...

Bob Larter wrote:

Michael A. Terrell wrote:
Bob Larter wrote:
My classic screwup was a time, as a smartarse teenager, when I was
working on a 28" display monitor, & /thought/ I'd discharged the CRT
correctly via the ultor cap. I lifted the ultor cap to unhook it, & a
giant spark bit me. The shock threw me clear across the room, & I just
missed slamming into a bench.


This explains a lot! ;-)

I suppose you've never zapped yourself? ;^)


Not like that. The HV I worked with wasn't measured in micro amps.
It was inside the TV transmitter. One touch, and you're dead. Think
what a HV DC power supply for three 65 KW Klystrons would do to you,
when the power supply put out a continuous 195 KW. In fact, you
wouldn't even need to touch it.


--
You can't have a sense of humor, if you have no sense!


Scares the crap out of me just thinking about it! I've only ever worked
consumer electronics, never had any training on high voltage / high
frequency power circuits.

I once got shocked by a GE 35" tv by only getting near the anode wire. The
wire had cracks in it, and I didn't know until it was too late. Felt like it
took my arm off!

More than once grazed some skin across 120 volts AC whilst working on
equipment; never got much more than a "Huh? What was that? Oh, crap. Gotta
be more careful..."


Mark Z.

On Fri, 8 May 2009 06:04:06 -0500, "Mark Zacharias"
wrote:



More than once grazed some skin across 120 volts AC whilst working on
equipment; never got much more than a "Huh? What was that? Oh, crap. Gotta
be more careful..."


Mark Z.

Funny thing is that 120 volts AC is actually more likely to kill you
than 240 volts!

Mark Zacharias wrote:

Michael A. Terrell wrote:

Not like that. The HV I worked with wasn't measured in micro amps.
It was inside the TV transmitter. One touch, and you're dead. Think
what a HV DC power supply for three 65 KW Klystrons would do to you,
when the power supply put out a continuous 195 KW. In fact, you
wouldn't even need to touch it.

Scares the crap out of me just thinking about it! I've only ever worked
consumer electronics, never had any training on high voltage / high
frequency power circuits.

I once got shocked by a GE 35" tv by only getting near the anode wire. The
wire had cracks in it, and I didn't know until it was too late. Felt like it
took my arm off!

More than once grazed some skin across 120 volts AC whilst working on
equipment; never got much more than a "Huh? What was that? Oh, crap. Gotta
be more careful..."


That is why there are so many safety interlocks in big transmitters.
I was moving a RCA TTU-25B transmitter about 15 years ago, and found a
small screwdriver jammed in one of the interlock switches. Luckily, the
highest voltage in that cabinet was around 350 volts DC, but several of
the other cabinets had 7000 VDC for the two water cooled power
tetrodes. The transmitter was in nine, four foot square aluminum
cabinets that were about seven feet tall. There were two, two foot wide
sections that held the special rubber pipe that isolated the HV from
ground. That made the entire transmitter 4 feet deep, 40 feet wide and
seven feet tall.


--
You can't have a sense of humor, if you have no sense!

"PeterD" wrote in message
...
On Fri, 8 May 2009 06:04:06 -0500, "Mark Zacharias"
wrote:



More than once grazed some skin across 120 volts AC whilst working on
equipment; never got much more than a "Huh? What was that? Oh, crap.
Gotta
be more careful..."


Mark Z.

Funny thing is that 120 volts AC is actually more likely to kill you
than 240 volts!

Only because you may be exposed to it a lot more often. Consider that at
240v you will be dissipating 4 times the power through your bod!

On Fri, 8 May 2009 06:04:06 -0500, "Mark Zacharias"
wrote:

"Michael A. Terrell" wrote in message
...

Bob Larter wrote:

Michael A. Terrell wrote:
Bob Larter wrote:
My classic screwup was a time, as a smartarse teenager, when I was
working on a 28" display monitor, & /thought/ I'd discharged the CRT
correctly via the ultor cap. I lifted the ultor cap to unhook it, & a
giant spark bit me. The shock threw me clear across the room, & I just
missed slamming into a bench.


This explains a lot! ;-)

I suppose you've never zapped yourself? ;^)


Not like that. The HV I worked with wasn't measured in micro amps.
It was inside the TV transmitter. One touch, and you're dead. Think
what a HV DC power supply for three 65 KW Klystrons would do to you,
when the power supply put out a continuous 195 KW. In fact, you
wouldn't even need to touch it.


--
You can't have a sense of humor, if you have no sense!


Scares the crap out of me just thinking about it! I've only ever worked
consumer electronics, never had any training on high voltage / high
frequency power circuits.

I once got shocked by a GE 35" tv by only getting near the anode wire. The
wire had cracks in it, and I didn't know until it was too late. Felt like it
took my arm off!

More than once grazed some skin across 120 volts AC whilst working on
equipment; never got much more than a "Huh? What was that? Oh, crap. Gotta
be more careful..."


Mark Z.

Oh, you should try working the CO frame in Palm Desert! Temperature
is about 90, even with the HVAC running full out, and you put your arm
across a set of pins just as ring voltage comes through.

ZAP! your arm jerks up...

OUCH! as you impale your arm on the pins above

ZAP! as your arm comes back down on the pins below just as another
ring hits...

OUCH!!!! as you impale your arm on the pins above again!

Usually, after about two hits you get control... ;-)

Charlie

On May 7, 8:56*am, Bob Larter wrote:
My classic screwup was a time, as a smartarse teenager, when I was
working on a 28" display monitor, & /thought/ I'd discharged the CRT
correctly via the ultor cap. I lifted the ultor cap to unhook it, & a
giant spark bit me. The shock threw me clear across the room, & I just
missed slamming into a bench.

Mine was moving the meter probe tips slightly while looking over at
the meter. Diodes explode into many fast moving pieces, and melt your
probe tips. Wear a full face shield, not just goggles, and a heavy
duty full sleeve lab coat. Remove watches, rings, necklaces, etc. If
you don't want a spark to hit it, don't put metal on it.

On 5/8/2009 3:06 PM Charlie E. spake thus:

Oh, you should try working the CO frame in Palm Desert! Temperature
is about 90, even with the HVAC running full out, and you put your arm
across a set of pins just as ring voltage comes through.

ZAP! your arm jerks up...

OUCH! as you impale your arm on the pins above

ZAP! as your arm comes back down on the pins below just as another
ring hits...

OUCH!!!! as you impale your arm on the pins above again!

Usually, after about two hits you get control... ;-)

Hah! That reminds me of that ditty about the Irishman hoisting bricks up
with a pulley ...

.... ah, there it is:

Why Paddy's Not At Work Today
(Tune: "In The Garden Where The Praties Grow")

Dear Sir, I write this note to you to tell you of my plight
For at the time of writing I am not a pretty sight
My body is all black and blue, my face a deathly grey
And I write this note to say why Paddy's not at work today.

Whilst working on the 14th floor some bricks I had to clear
To throw them down from such a height was not a good idear
The foreman wasn't very pleased, the bloody awkward sod
And he said I'd have to cart them down the ladders in me hod.

Now clearing all these bricks by hand, it was so very slow
So I hoisted up a barrel and secured the rope below
But in my haste to do the job I was too blind to see
that a barrel full of building bricks was heavier than me!

And so when I untied the rope, the barrel fell like lead
And, clinging tightly to the rope, I started up instead
I shot up like a rocket til to my dismay I found
That halfway up I met the bloody barrel coming down!

The barrel broke my shoulder, as toward the ground it sped
And when I reached the top, I banged the pulley with my head
I hung on tightly, numb with shock, from this almighty blow
And the barrel spilled out half the bricks, 14 floors below.

Now when these bricks had fallen from the barrel to the floor
I then outweighed the barrel, and so started down once more
Still clinging tightly to the rope, my body racked with pain
When, halfway down, I met the bloody barrel once again!

The force of this collision, halfway up the office block
caused multiple abrasions and a nasty state of shock
Still clinging tightly to the rope, I fell towards the ground
And landed on the broken bricks the barrel scattered round!

I lay there, groaning, on the ground; I thought I'd passed the worst
But the barrel hit the pulley wheel, and then the bottom burst...
A shower of bricks rained down on me; I hadn't got a hope...
As I lay there bleeding on the ground, I let go the bloody rope!

The barrel it was free to fall, and down it came once more
And landed right across me, as I lay upon the floor
It broke three ribs and my left arm, and I can only say:
That I hope you understand why Paddy's not at work today!


--
Save the Planet
Kill Yourself

- motto of the Church of Euthanasia (http://www.churchofeuthanasia.org/)

"JB" wrote in news:C31Nl.69$5F2.54
@nwrddc01.gnilink.net:


"PeterD" wrote in message
...
On Fri, 8 May 2009 06:04:06 -0500, "Mark Zacharias"
wrote:



More than once grazed some skin across 120 volts AC whilst working on
equipment; never got much more than a "Huh? What was that? Oh, crap.
Gotta
be more careful..."


Mark Z.

Funny thing is that 120 volts AC is actually more likely to kill you
than 240 volts!

Only because you may be exposed to it a lot more often.

No! Because 240 is more likely to 'throw you off' and 120 is more likely to
'freeze you on'.

15 micro amps across the heart kills. 60 Hz is especially bad for causing
V-fib. Without a defibrillator, or CPR you are dead in 6 minutes.

15 milli amps is sufficient to 'freeze your muscles' so you can't let go.
You start with relatively dry skin and get a good grip onto a hot item.
You can't let go.
Skin at the points of contact blisters.
resistance goes down.
current goes up.
you cook.

Higher voltages produce very violent muscle contractions and can (if you
are lucky) throw you clear of the circuit.


Consider that at
240v you will be dissipating 4 times the power through your bod!







--
bz 73 de N5BZ k

please pardon my infinite ignorance, the set-of-things-I-do-not-know is an
infinite set.

remove ch100-5 to avoid spam trap

On May 6, 7:36 am, 1PW wrote:
On 05/04/2009 04:52 AM, sent:

Hi,

I'm going to do some experimentation on high voltage equipments
( transformers, power supplies, capacitor banks, lasers , etc.. ).

Does anyone know where I could find some safety guidelines or notes
about working with this dangerous stuff ?

( I wouldn't like to die because of a spark jump and make my wife a
widow... )

Thanks

Stef

Hello Stef:

Please define the levels of high voltage you are referring to.

Laser safety is also an entirely different subject. What type & class
laser?

Pete
--
1PW @?6A62?FEH9E=6o2@=]4@ [r4o7t]

I refer to voltages found for example in CO2 lasers and CRT chassis.

I found a nice page with guidlines: http://www.repairfaq.org/sam/safety.htm

Is there a rule for how long a spark can jump, given the voltage and
the dielectric ( tipically air at certain humidity) ?

Furthermore, why should I keep a hand in my poket while around HV ?