I use 12 ft 2 prong extension cord as my standard replacement, polarized etc.

https://pinside.com/pinball/forum/topic/replacing-line-cords-plugs-wall-sockets-vids-guide

Steve Young's are nice and are grounded too, which is nice.

Just bought 2 from PBR. I like the fact they are 14' long which makes reaching an outlet a breeze.

You are better off getting a cord rated at or above the amp rating of your machine. Lamp cord typically is handling 60-100W light bulbs. Pinball machines typically pull more power than that and you wouldn't want to melt the cord and cause a fire.

If you are impatient like me, I go to Walmart and get rated extension cords of the length I am looking for and cut off the outlet end.

ken

I have bought cords at Home Depot, or Lowes

No, it's not okay. Today's electrical standards use a grounded plug (and outlet) and you should upgrade the cord and install ground braid as described in Vid's guide, post 15. https://pinside.com/pinball/forum/topic/replacing-line-cords-plugs-wall-sockets-vids-guide#post-1945124

Then when you're done turn all your machines on and check to see if any voltage is present when you touch the leads of your DMM to adjacent machines. If any is present fix it immediately.

If you use one of Steve Young's cords note that if your machine still has the retaining metal band for the cord under the head, it will need to be removed, or you will have to remove all the sheath to the point where your wires go under the metal part. They are made to hold flat cord with 2 conductors, not rounded with 3. You may also be able to take a circular file to the wood under the metal.

You can certainly ground the game if you want... but a two prong cord should be similarly safe. Woodrail vs. metal rail. EM vs. SS. If you have a lineup of DMD machines with the ground cut off or not - there's no exposed metal that can shock you on a bingo (at least that I can think of). And if there were, the maximum is 50V. Also, the doors are wooden - just less possibility of shock.

Bingos are great to work on as a result.

I usually use one of the cords that Steve Young sells and cut off the green wire inside the sheathing. Most of my games don't have the metal retaining plate any longer.

Nick,

Why not hook up the ground to the transformer leg, originality?

I only have one bingo and don't understand what the metal retaining plate looks like. Can you show me a picture please.

Hey Steve, you can hook the ground to the transformer plate - assuming that it's not rusty or otherwise a poor conductor. But what's the point? It's certainly possible I have a fundamental misunderstanding.

But if the transformer is grounded and nothing else is... what are you protecting? The transformer will be grounded, but everything else in the game will float.

The metal retaining plate is a very small oval-shaped thick piece of metal that goes across the power cord channel cut into the bottom of the head (on a Bally). It's frequently missing. I don't have any pics, but I'll see if I can snap one next time I'm under a game. It's really small and basically is nailed to either side of the power cord channel.

I hate grounded EM games, I shock myself more times then not on those games. I like to be floating myself when I touch the hold relay or bank reset contacts on the score motor...and Im invariably leaning on the siderail.

Always ground EM games and old guitar amps.

It will save your life someday.

Agreed - with the exposed wiring inside of a game, and using a ground braid as Vid recommends in the linked post above, it will be trivial to shock yourself quite badly. Touch the exposed braid and the exposed power side of the relay bank. OUCH! Now you have 50V flowing nicely to ground. Through your body. Hope you didn't touch the motor wiring! That's 120V. Without grounding, you'd have to touch both lugs.

Metal rails can be a problem. Coin doors too. But we're not talking about metal rails.

I may just misunderstand.

Truly, I would like to know how, in a woodrail bingo, with their much higher quality of insulation between the buttons and the player... how you'd get shocked. I would also love to know how you suggest 120V would get to you. No, 50V is not safe, but it's a heck of a lot better than the 120V on the coin door of Gottlieb woodrails.

My point is that the same approach does not work for everything. I consider safety a high priority. That includes my safety as a technician. You're not preventing damage to people, nor equipment by grounding a bingo... at least as I understand it.

Wooden legs, wooden rails, wooden coin door, no more than 50V exposed even through a short (and there is very little wiring that could even reach the components that matter in the coin door (buttons).

There's no coin slot on the front door, etc. There's no exposed metal that can possibly come into contact with any wiring whatsoever inside a bingo except for the buttons on the front. And it would be a very dark day indeed (fuse blown) if that did happen.

If I'm putting myself or others in danger with that line of thinking I'd be happy to understand it so that I can keep others safe.

While I agree with grounding solid state and some other games, in this particular case I think it overkill and you're likely to get hurt doing it or cause damage to the game. Or if just grounding the transformer, not really doing much to help.

When everything is perfect, the chance of electrocution is slim.

It's when things go wrong that people die.

Outlets reverse wired, non polarized plugs, transformer heats up past insulation point, past hack creates danger, part falls from playfield into relays........

Any metal part that can be touched by the player, should be grounded.

If there is absolutely no metal that can be touched by the user, then at least ground the transformer case for protection from insulation breakdown.

Agreed, test your outlets.

We're talking about swapping the cord. Hard to buy a non-polarized plug these days.

Then you'll have a different problem. You'll likely notice the game smoking at that point... and the smell of wax burning! Line fuse will blow.

Look over your game. Again, unless someone ran a bunch of wires to somewhere they shouldn't be and left them uncapped (will be very obvious).

It's a nice idea. But, again, if I ground my leg bolts, what is that really gaining me?

Fuses. This is the same protection that has existed for this for decades. It's cheap, & pretty darn reliable.

When the transformer shorts from wax melting it will either catch fire or blow the line fuse. Maybe both!

You can try and defend laziness all you want, but it takes 2 seconds of extra work to make a game safer.

Williams was famous for taking every shortcut possible in their games, but you note that even the speaker grills are grounded on the bottom of the game.

They did not say "Who the hell goes under a game to touch the speaker grill?", they simply made the game safe for any possible electrocution scenario.

Like they always say "A good circuit is not the circuit that works when everything is fine, a good circuit is one that does not burn the house down when the unexpected fails"

Sure they did. In games with circuit boards.

If only because of ul requirements or to protect the safety of their boards.

Laziness is possible sure. Using a ground braid is still dangerous.

Better to use a ground strap. But again, you're gonna need to ground every stepper, every motor mount, every everything. You're much more likely to screw up that hack than to replace the cord correctly.

But that's both sides of the argument.

Think about this: my 90% metal toaster purchased in the last two years is not grounded.

Nick, can you post a picture of the inside of a bingo that you think would not be safer using a three prong grounded cord & ground braid?

You've raised some good points. Thanks for contributing to the topic.

Do whatever you want as long as you kill yourself and not some kid or something.

-

Last year I sold a '68 Marshall Plexi amp to a guy who said he was a "serious collector" and wanted the most legendary amp ever built.

I had the amp open so he could see all the original circuitry.

I pointed out that I had removed the Death Capacitor, disabled the Polarity Switch it was connected to and that the amp was now grounded to UL code with a 3 prong cord (a 5 minute job).

He started going crazy that "the amp was no longer original".

I explained that if the Death Cap dies (and it WILL die at some point, it's a capacitor), he would be killed with that sweaty guitar in his hands.

His logic was that guitarists played those amps for years, and only a few have been killed (like Keith Relf from the Yardbirds) or burned and knocked unconscious (like Ted Nugent and Ace Frehley from KISS).

I handed him a ziploc bag with the Death Cap and the old 2 conductor power cord, and told him that if HE wanted to put it back in, he could do so; but I was not having anything to do with that nonsense if some kid touches his guitar someday and gets killed.

He begrudgingly bought the amp and took his bag of death with him.

He emailed me a few months ago about what new tubes to buy for the amp, and I asked if he "restored" the amp back to factory yet. He said he tried to get the local music store tech to do it, and they told him he was "fncking crazy".

Safe minds think alike.......

This statement instantly shows that you do not understand even basic electrical theory.

PLEASE, stop giving advice about things you know nothing about.

Again, you don't understand the basics.

A toaster is a double insulated (Class II) appliance and requires no grounding.

Which basic electrical theory principle applies to his statement and how does that principle being mis-applied make his games less safe?

"The path of least resistance"

A properly functioning Safety Ground Braid can not make a game more dangerous.

Except mine is not class II. I did learn about appliance classes, so thanks for that! Mine does not have the double square symbol printed anywhere on the sticker, impressed into the body, etc. (I should probably get a new toaster...) I won't cut the power cord open to verify, but the other indicators are missing.

Man, you're absolutely right - I made a blunder up there (duh! Sorry, gonna chalk that up to the crummy week I've had.) - you cannot be shocked by touching both ground and hot (that's the whole thing it protects you from...) - if the ground is properly isolated/connected throughout. That was my fault. If there's tingles, no, it's not properly connected somewhere. You're right that you will not be injured, however, you will be tripping the breaker if the braid comes into contact with something odd.

Here's the thing, the inside of a bingo door contains two stacks of switches. There's also a coin mech. The outside of a bingo door contains two buttons - red and yellow. Depending on the year, they were either plastic or metal. The metal ones have a non-metal covering/end that actually presses the switches (I don't know what kind of covering it is - it is black and feels like rubber). There are also heavy-duty switch insulators there, too. It does depend on the vintage.

What can short? The switches could short if the insulator fails. The switches could short maybe somehow if the button was destroyed inside the coin door... what would happen? Well, if the insulator fails, then you will get a quicker press of the start relay, or your 50V fuse pops.

If the button insulation fails, then it's theoretically possible you could be shocked.

Ditto for the coin return button. There's a coin lockout relay which sits under the mech. If someone clipped a lead and didn't tape it, then the coin return could shock you.

If the ground braid/strap is installed inside the coin door and attached to the button inside (that'll be a trick, [the inside of the button mostly sits in a small routed channel] but doable) then yes, you would be prevented from a risk of a shock.

So to recap, a ground will prevent risk of shock. On a woodrail bingo with three metal components... I find any scenario to be highly unlikely that would cause a shock. I realize that it is protection against the outliers.

P.S. sorry for the delay in responding - I was playing my deathtraps.

Thank you. yup I believe I have that.