what is the worst that can happen if you wire NC and NO wrong on coin switch?

vintagegamer

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what is the worst that can happen if you wire NC and NO wrong on coin switch?

I am working with a Williams game where someone decided to pull the wires off of the coin switch and just touch them together to credit up. The coin switch is there and it's fine.

I have not yet gotten to find the spec that shows which wire is NC and which is NO, but one of the wires is black and one is white.

My basic question is, if I accidentally have them reversed when soldering them to the coin switch, what is the worst that will happen on a Williams game? Will it cause damage? Just not coin up? What will happen?

I want to get the schematic for the game but am just setting up a plan 'B' here.

Thanks!
 
If it's just two wires I would think one was ground and one went to the NO position. The NC position on the coin switch was probably not used.
 
My basic question is, if I accidentally have them reversed when soldering them to the coin switch, what is the worst that will happen on a Williams game?

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Worst case scenario, the game won't boot with a "coin switch failure" or similar error, that clears itself when you wire it the right way. Very few games actually do that though, and most that do will let you bypass the error and boot anyway somehow.

There's ALWAYS a wire on COM. There's a few odd games out there that have three wires, COM/NO/NC as a fault-checking measure, but if there's only two, it probably doesn't matter, NC or NO, though if it's wired NC a damaged wire can erroneously coin up the game.
 
Worst case scenario, the game won't boot with a "coin switch failure" or similar error, that clears itself when you wire it the right way. Very few games actually do that though, and most that do will let you bypass the error and boot anyway somehow.

There's ALWAYS a wire on COM. There's a few odd games out there that have three wires, COM/NO/NC as a fault-checking measure, but if there's only two, it probably doesn't matter, NC or NO, though if it's wired NC a damaged wire can erroneously coin up the game.

Sorry, I forgot to mention that on the coin switch, there is already a wire soldered to the center tab (I'm guessing it's the COM tab but haven't looked at it very specifically yet).

I have to wait until the weekend to futz with the game more, unless I ended up with someone here saying "nope it won't blow up" and then I can randomly solder the wires on tonight. If you touch the blk and white wires together currently, it generates a credit and works fine. I just hate how the whole dangling wire thing looks inside, especially when I've now been able to learn the art of the soldering iron!
 
Sorry, I forgot to mention that on the coin switch, there is already a wire soldered to the center tab (I'm guessing it's the COM tab but haven't looked at it very specifically yet).

I have to wait until the weekend to futz with the game more, unless I ended up with someone here saying "nope it won't blow up" and then I can randomly solder the wires on tonight. If you touch the blk and white wires together currently, it generates a credit and works fine. I just hate how the whole dangling wire thing looks inside, especially when I've now been able to learn the art of the soldering iron!

nope it won't blow up. There you go ;) In all seriousness, as I said, worst case scenario, it'll prevent the game from booting but not actually damage anything.

The center tab is usually NO actually, but if crossing the other two wires produces a credit, maybe not. Or maybe that wire shouldn't be there, and the other two were desoldered because the PO was a dipsnot and couldn't figure out the real problem so he came up with that hack.

The switch poles should be labeled right on the switch body. If not, you can figure it out with a multimeter (out of circuit) -- in resting position, COM is shorted to NC, and NO is open/floating; when tripped, COM is shorted to NO, and NC is open/floating. If you get anything else, the switch is BAD and you should replace it.
 
Just put your meter on two tabs of the switch and see if registers as closed. If not, then actuate the switch to see if it closes when actuated. When you find two tabs that change from open to closed when the switch is closed, connect your wires to those two tabs. It doesn't matter which wire goes to which tab...
 
Thanks guys for your input- I don't want in any way to come off like I'm being lazy, I just seem to get more time to 'think' about what I need to do to my games these days, as opposed to getting time to 'work' on them. I'll be able to mess around more by the weekend, I'm just trying to get some plans of attack in place. :D
 
I got to check it out (finally) and the order of the tabs is as follows:

COM (closest to outer edge of door, NO, then NC..

Currently there is a black wire w a red stripe soldered onto the NO tab, and the 2 loose wires that when touched together allow the game to credit up are white and a 2nd black wire w/red stripe.

Is there a damn manual for this cocktail game (Defender)? All I keep finding are the "Theory of Operation" manuals. I don't want to be enlightened, I just want to wire up the friggin' coin switch. :)
 
I got to check it out (finally) and the order of the tabs is as follows:

COM (closest to outer edge of door, NO, then NC..

Currently there is a black wire w a red stripe soldered onto the NO tab, and the 2 loose wires that when touched together allow the game to credit up are white and a 2nd black wire w/red stripe.

Is there a damn manual for this cocktail game (Defender)? All I keep finding are the "Theory of Operation" manuals. I don't want to be enlightened, I just want to wire up the friggin' coin switch. :)

touch the white to the other black/red wire, the one soldered to the tab. Does it coin up?

I'd wager the wiring is set up for two coin mechs, and you're seeing the ground wires for both mechs (black/red) and you missed the fourth wire (NO for mech 2). You can safely switch the two as microswitches aren't polar in the way diodes or capacitors are -- current flows either way, they don't care.
 
touch the white to the other black/red wire, the one soldered to the tab. Does it coin up?

I'm gonna try to mess with it some more today, but the PS is quickly dying. I've ordered a cap kit from Bob Roberts but with the PS on the fritz my troubleshooting skills are way limited right now.

Cripes- first I didn't have the time and had the game at home. Now I'm home and the game is home, but the PS is dying. If I didn't want to put my Robotron in jeopardy I'd pull the PS from that and start doing some Frankensurgery LOL
 
I'd wager the wiring is set up for two coin mechs, and you're seeing the ground wires for both mechs (black/red) and you missed the fourth wire (NO for mech 2). You can safely switch the two as microswitches aren't polar in the way diodes or capacitors are -- current flows either way, they don't care.

OK I was able to mess with the game some more today, and it *is* as roothorick has mentioned. If I touch the white wire to the black/red one that's currently soldered to the the NO tab of the switch, yes it will credit up.

So, what is the best way to solder up this switch so it is safe and accurate? Again, the COM is closest to the edge of the door with nothing on it currently, followed by the NO tab in the middle of the switch (and currently has one of the 2 black-red wires attached to it), and then the NC tab at the inner-most point with no wire currently on it.

Thanks again to all for the help!
 
it's a coin switch. the ground goes to the COM, the coin wire goes to the NO.

am I missing something?
 
it's a coin switch. the ground goes to the COM, the coin wire goes to the NO.

am I missing something?

Sorry I know it sounds like a butt-stupid question, I'm just getting confused bc I don't know if the black-red wire that is on the NO tab of the switch currently was there originally from the manufacturer, or if someone rigged it trying to bring the game back to life, and I didn't want to make any further mistakes.

I guess this means I can solder the white wire to the COM tab and call it a day?
 
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