Tips for not electrocuting one's self...

[timsatari]

Anyone have some tips (besides turning off / unplugging cab) before tinkering inside? I understand that the arcade monitor could burn yourself an extra a-hole (out the back of your head). What are some basics to prepare yourself? Do you need a ground strap of some sort?

Thanks!

[Tailgunner]

Well if it's off/unplugged you've eliminated the majority of danger. As you mentioned, the high voltage circuit of the monitor can give a nasty bite, another possibility might be the big blue capacitor on an Atari power supply. Other that that, I think you'd be more likely to damage a circuitboard via static discharge than to electrocute yourself.

[grafixmonkey]

You can't electrocute yourself (or even really feel anything) with 5v, 12v, or 24v contacts.  Maybe if you touched your tongue to them, but not through your hands.  You probably already knew that, but hey I've had people ask me about electrocuting themselves in a 12v circuit before.  

Anyway, you're extremely unlikely to find any voltages higher than those anywhere except the power supply and monitor.  Some cabs might have high-voltage lamps, I've seen washing machines with 80v lamps inside them before, but those won't have voltage when the lights are off, and most arcade lamps are in the 12v range anyway.

[Gideon]

I thought this was an interesting read (in case some one hasn't seen it).

[Thenasty]

its not the Voltage that kills, but the Current will make sure you go 6 feet under  

[mahuti]

I touched a "hot" wire on the arcade cabinet once. I"m not going to do it again, but it wasn't a big deal... a mild electrical heating sensation.

[SNAAAKE]

oh yeah me too.I touched an isolation transformer(speaker) PZZttt...It was funkay


(never try it though,lol)

[dragonbrood]

...and make sure that if you ar stupid enough to mess about with pc monitors that the tube is STILL conencted when you place it into your cabinet....as i found out lol i ---steaming pile of meadow muffin--- myself when i powered it on inside the cabinet hearing the LOUD pops and bangs!

[JoeB]

Get yourself good tools, and don't try to skimp on them!

Good screw driver set with rubber or plastic handles, and even more imprtantly, 100% plastic screw set to tweak pots.  The worst thing you can do is rotate pots on a monitor with a metal screw driver! You won't kill yourself, but you can seriously damage the monitor!

[grafixmonkey]

its not the Voltage that kills, but the Current will make sure you go 6 feet under  

yes, but human skin has a very high resistance, so you need a high voltage to produce a high current through yourself.  Voltage and current are linearly dependent - can't increase one without increasing the other.

[grafixmonkey]

Hehe, I was repairing a friend's computer once, trying to find out why it was crashing first time it was turned on after about 20 minutes, then every 5 minutes after that.  It involved taking a fan off of the power supply, and I found out the hard way that the big heatsink inside was connected directly to the live wire.  

You know, this forum really needs an "electrocution smiley", that turns black and has sparks fly out of it.

[slicer_d]

Correct me if I'm wrong but dont (most) PC monitors have metall cages beneath the plastic cages to keep you from touching anything nasty?  I was planning on either looking this up or posting the question later but this seemed like a good place to do it.

[Burtrude]

dont stick your finger in the hole in the monitor with the big lightning bolt sticker above it ... trust me  ... not having use of your arm for a while aint fun  

and also don't believe people when they tell you "yes the power is off" ... make sure it is off yourself, saves you having to bash them when you get zapped from the power supply

[Thenasty]

I think we are to late  

He has not responded at all.  

[Spartan]

Don't stick a screwdriver under the suction cup of the monitor while not wearing shoes and standing on a concrete floor.

(Please don't ask how I know this.)  

[Tailgunner]

Don't stick a screwdriver under the suction cup of the monitor while not wearing shoes and standing on a concrete floor.

(Please don't ask how I know this.)  

Sounds something like how I learned to not play with a neon tube transformer when it's plugged in. Shoes didn't help, 30,000 volts is more than enough to overcome their insulative properties.

[APFelon]

dont stick your finger in the hole in the monitor with the big lightning bolt sticker above it ... trust me  ... not having use of your arm for a while aint fun

I took a hit from a discharged tube once. I was trying to keep it from falling out of a cab with a reclined mounting shelf (Turtles in Time 4p dedicated) and I threw my arm up to catch it. Touched that hole and...

I nearly pissed myself. Unfun.

APf

[paigeoliver]

I wouldn't worry too much about big blues, I went on a big blue swapp-a-thon recently in attempts to get my Sprint One working and my Crystal Castles to stop resetting, anyway, I installed all 4 of my big blues in each one of my Atari cabs in a short time span, and got no shocks whatsoever, and I didn't take any precautions at all.

[mmmPeanutButter]

Correct me if I'm wrong but dont (most) PC monitors have metall cages beneath the plastic cages to keep you from touching anything nasty?  I was planning on either looking this up or posting the question later but this seemed like a good place to do it.

Yea, my monitor does.  the other day I took off all of the plastic casing and I was checking out the insides.  I was leaning in to get a better look and got a small static shock from the metal casing to the tip of my nose.  I must have jumped 5 feet.  Man, did that ever scare the crap out of me.  

I plan on doing a rotating monitor, so I'm planning for the wooden monitor support.  I can get all of the plastic off except for the very bottom one.  Unfortunatly, I have to remove the cage before I can get off the screws.  So I don't know if I should remove the cage, then the plastic and then put the cage right back on... or, take the monitor into a repair place to get it discharged first...

Half of me doesn't want to die, but the other half of me doesn't want to get gouged by the TV repair guy.

Does anybody know how much it would cost to get my monitor discharged by a professional??

[NoOne=NBA=]

The power is never REALLY off when you're dealing with a monitor or picture tube.
The capacitors that let it "fire right up", instead of taking forever like the old tube TV's did, also keep it charged electrically when the power is disconnected.
Discharging it is a good preventative measure, but I wouldn't even trust discharging completely.

I'm sure there are some really good threads on this somewhere, but I don't know of any offhand.

[grafixmonkey]

Well, as far as how to discharge them, the Monitor/Video forum would be a great place to get that info (it's probably scarce in the Main Forum) but I think the main arcadecontrols.com website has plenty of info on that too.  

I've never done it personally, but I've read the threads, and what I gather is that there's one capacitor that holds the charge and if you discharge it you're safe from then on.  Technically, you have to try really hard and use special electronics and/or carefully planned timing to be able to partially discharge a capacitor.  You can't do it with a simple wire or screwdriver, it's impossible.  If you tried to discharge it while it was still plugged in, there would obviously be charge left in it, but I think if you did that the charge left in the cap wouldn't be your biggest problem.  

From what I read, it is DEFINITELY NOT something you do without fully reading up on the subject.  (I heard a story about someone doing it improperly with a screwdriver, hitting the wrong contacts, and his arm muscles got the full shock - he looked across the room and his screwdriver had been thrown and embedded the metal shaft into a piece of solid wood.   )

[paigeoliver]

It IS NOT A CAPACITOR that you are discharging when you discharge a monitor. It is the tube. Sure, some of the caps might be holding a some charge, but that is small potatoes (nothing to worry about). I have worked on tons of monitors and never gotten any kind of shock from a capacitor.

Tube discharging is not hard, and stops being scary after the first or second time.

And most PC monitors do not have a metal case inside the plastic one.