how to convert a service plug outlet from 2-prong to 3?

vintagegamer

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how to convert a service plug outlet from 2-prong to 3?

I'd like to switch out (if poss) the 2-prong service outlet in my Monaco GP to a 3-pronger. That way, I can use the original power switch and power transformer to power up the power strip which all of the other components are plugged into (I MAMEd this game for those who don't already know).

I know that you can get one of those 2-prong to 3-prong adapter mo-bobs, but I'm always concerned about how safe those things really are.

Now taking suggestions!
 
Just use one of those adapters, but be sure to wire the ground lug (little ring on the adapter) to ground in the game (where the line cord enters, green wire).

Or, replace it with a three prong outlet.

-Ian
 
The two to three prong adaptor would work fine, you just need to hard wire the third prong back to the cabinet field ground (third prong on the cab power cable).

You could also replace the two prong outlet with a three prong outlet, again you'll have to run the extra wire since the cab is not already wired for the service outlet ground.
 
I will have to check later tonight, but I'm thinking that the original power cord on the game got hacked by a prior owner and now is only running a 2-prong cord. I will have to verify this.

Thank you for the feedback OZ!
 
It's circled in yellow in the attached pic.

Is that what the monitor is plugged into in the picture? That might be the output of the isolation transformer, like Donkey Kong. In which case, you'll want to install a new outlet, but tap it off before the isolation transformer.

Also, if the power cord is now a 2 prong cord, a three prong outlet isn't going to do you a damn bit of good, as the game still has no ground. You need to replace the cord with a three prong one if you want it to be safe.

-Ian
 
Is that what the monitor is plugged into in the picture? That might be the output of the isolation transformer, like Donkey Kong. In which case, you'll want to install a new outlet, but tap it off before the isolation transformer.

Also, if the power cord is now a 2 prong cord, a three prong outlet isn't going to do you a damn bit of good, as the game still has no ground. You need to replace the cord with a three prong one if you want it to be safe.

-Ian


Yep, that's where the monitor was plugged in. Hmm..

And yeah, I'm pretty sure someone hacked up the cord. My whole goal with this idea was to be able to leverage the original power switch without having to rig that to something else to make it "look" original. As usual the project requirements list is expanding faster than I can keep up with LOL
 
Yep, that's where the monitor was plugged in. Hmm..

And yeah, I'm pretty sure someone hacked up the cord. My whole goal with this idea was to be able to leverage the original power switch without having to rig that to something else to make it "look" original. As usual the project requirements list is expanding faster than I can keep up with LOL

Don't worry, this is really simple.

Replace the power cord with a 3 prong kind. Running a game (or a computer) without a ground could be dangerous.

Don't use the existing two prong outlet, since that's likely 100v output (japanese game) anyway. Also, the isolation transformer is meant to power one monitor, and little else. You might overload it and start a fire.

Simply find the AC wiring where it goes into the old game's power supply or isolation transformer, and connect your new outlet there. Don't forget to hook up the ground to your new outlet too. I would just use a standard duplex outlet and a surface mount "handy box" from the hardware store - total cost of about three bucks.

-Ian
 
Don't worry, this is really simple.

Replace the power cord with a 3 prong kind. Running a game (or a computer) without a ground could be dangerous.

Don't use the existing two prong outlet, since that's likely 100v output (japanese game) anyway. Also, the isolation transformer is meant to power one monitor, and little else. You might overload it and start a fire.

Simply find the AC wiring where it goes into the old game's power supply or isolation transformer, and connect your new outlet there. Don't forget to hook up the ground to your new outlet too. I would just use a standard duplex outlet and a surface mount "handy box" from the hardware store - total cost of about three bucks.

-Ian

I will be checking this out tonight. Thanks again!
 
I'd like to repeat what RH said. That is not a service outlet, it is a monitor power outlet and is almost certainly 100vac. A service outlet is wired in before the iso and is just a pass through for the mains power.
 
I'd like to repeat what RH said. That is not a service outlet, it is a monitor power outlet and is almost certainly 100vac. A service outlet is wired in before the iso and is just a pass through for the mains power.

Really glad you guys pointed that out- it would have sucked if I'd wired it up and blew something up. :(
 
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