Power Supply Wiring?

zzaz3

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I'm about to try and wire my power supply. *I've read about this on all different sites and I found a nice diagram too. *Usually I'm pretty good at figuring these things out, but since it's the power supply I thought I should ask for help first just to be safe. *I'm just confused about one thing.

Here's my diragram:
basic-ac.gif


I understand most of it, except the OUT. *Which wires are which? *Where exactly should each one go?

Here's my setup:
IMG_0935.jpg


And:
IMG_0939.jpg


These are the wire's I'm confused about:
IMG_0940.jpg



Also, one more quick question. *Does the Earth Gnd really matter? *What does it do?
 
Pretty sure..

One of the sites has a picture of one like mine. (without the shell)

iso.jpg
 
Am I that picky... or am I the only one that doesn't like EVERYTHING being on 1 fuse. For that setup, I'd still rather have 2, maybe 3 fuses. Monitor, marquee, and maybe the switcher... would save hassle in the future if your ballast goes out, bridge goes out, or power supply boo-boos.

But, for what it is... yeah, that looks right.

You'll have to check the wires coming out to see which are putting out "115"VAC... I'd bet White and Black?... assuming that's the output side.

Earth ground is always good to hook up to everything you can think of (coin door frame, CP, etc etc etc) grounds them to prevent shocks (either the machine shocking you, or you shocking the machine). You'll see that on some machines where the door or CP are hooked up, you can drag your feet across the carpet and touch the machine and it'll either freak out, reset, or fry (haven't seen the "fry" one yet).
 
Am I that picky... or am I the only one that doesn't like EVERYTHING being on 1 fuse. For that setup, I'd still rather have 2, maybe 3 fuses. Monitor, marquee, and maybe the switcher... would save hassle in the future if your ballast goes out, bridge goes out, or power supply boo-boos.

But, for what it is... yeah, that looks right.

You'll have to check the wires coming out to see which are putting out "115"VAC... I'd bet White and Black?... assuming that's the output side.

Earth ground is always good to hook up to everything you can think of (coin door frame, CP, etc etc etc) grounds them to prevent shocks (either the machine shocking you, or you shocking the machine). You'll see that on some machines where the door or CP are hooked up, you can drag your feet across the carpet and touch the machine and it'll either freak out, reset, or fry (haven't seen the "fry" one yet).

Adding fuses sound like a good idea. The safer the better. But I just don't know enough about this power supply stuff to do that. Not to mention I like to do as little work as possible. :D

So does it matter which red wire goes where? Will that effect the output?

There's a label on the side of it. Idk what it means, maybe you will. I'll upload a picture.
 
Dangit, it's too small to get a clear picture of it. I'm going to try to redraw the diagram in paint. 1 second.
 
Ok, I got it. It's pretty messy though.
 

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You have an isolation transformer that has a "dual primary". This means it can be fed 240 volts or 120 volts depending on how it's wired. If wired for 240 volts, it will step down the output to 120 volts. If wired for 120 volts the output will be 120 volts.

The two red wires are the 120 volts output to the monitor.

The power input to the transformer for operation on 120 volts is as follows:

Connect the gray and blue wires together. These connect to the AC HOT side of the power line.

Connect the yellow and black wires together. These connect to the AC NEUTRAL side of the power line.
 
Ok that is an isolation transformer. It has a Primary which can operate on either 220 VAC or 120 VAC and the secondary is 120 VAC
You want the Primary running off 120 VAC so you hook the Blue and Grey wires to one side of AC coming off the EMI filter and the Black and Yellow wires off the other side of the AC out of the RCI filter.
The 2 red wires are the secondary 120 VAC output that goes to the AC monitor plug to power the monitor.
 
Bob has complete instructions for that build...... source of your diagram.
http://www.therealbobroberts.net/acwiring.html
The distribution block he uses in his example.
http://www.therealbobroberts.net/acblock.jpg

Of course a fuse block could also be used in place of a straight distro block if you wanted as well.

Oh, I didn't think it would would without the AC block. I'll look into that some more now. Thanks so much!!


You have an isolation transformer that has a "dual primary". This means it can be fed 240 volts or 120 volts depending on how it's wired. If wired for 240 volts, it will step down the output to 120 volts. If wired for 120 volts the output will be 120 volts.

The two red wires are the 120 volts output to the monitor.

The power input to the transformer for operation on 120 volts is as follows:

Connect the gray and blue wires together. These connect to the AC HOT side of the power line.

Connect the yellow and black wires together. These connect to the AC NEUTRAL side of the power line.


Does it matter which red wire goes where? Also, where should the last two wires go? I mean, I'm guessing the power supply, but does it make a difference which goes where?
 
Alright guys, does this look right?

IMG_0973.jpg

No it's wrong
You got the 2 red wires going to the power supply.
They should go to the monitor.
What are you trying to build anyway?
What's it going in?
And what's with all the wire splicing and electric tape?:eek:
You have no earth ground connected to the Isolation transformer or to the power supply.
And if you got the AC plug wires you spliced in hooked up backwards well that could be a real shock :eek:
 
Wait, so this will only power up the monitor? How can I send power to the board?

Sorry about all the 'splicing'. I don't know how else to do it.


If I get what wires mixed up?! The two red ones? I thought it didn't matter which one goes where.

If your talking about the 3 prong outlet, I did that right. I just tested it by plugging a lamp into the outlet and then plugging the whole thing in. I was real nervous, but luckily I got it right :D
 
Wait, so this will only power up the monitor? How can I send power to the board?

Sorry about all the 'splicing'. I don't know how else to do it.


If I get what wires mixed up?! The two red ones? I thought it didn't matter which one goes where.

If your talking about the 3 prong outlet, I did that right. I just tested it by plugging a lamp into the outlet and then plugging the whole thing in. I was real nervous, but luckily I got it right :D

The purpose of an isolation transformer is to power the monitor but more important it's to isolate the AC that powers the monitor from the AC that powers everything else. That's why it doesn't matter about hooking up the red wires to the monitor because theirs no ground thought that circuit. The monitor frame is still grounded though the earth ground, the green wire in the AC line cord you plug in the wall socket.
It does matter which wire you hook up to the AC line filter, the little metal box with black, white and green wires on the AC input side and a black and white on the AC output side. If all you want to power is the switcher power supply then run the 2 wires, the black and white from the RFI filter AC out side to the 2 AC terminals you now have the 2 red wires hooked to. The 2 red wires are ment to power the monitor so if you are not gonna use a monitor then nothing hooks up to them.You can splice into the same wires that go to the other side of the isolation transformer but if you don't need to power a monitor you can unhook it as you wont need it.
It will work the way you have it now but it's not right. As for the AC cord you spliced in, you got a 50/50 chance of getting it right or wrong. That type of core is not color coded but if you look at the cord one side of the wire has ribbs and the other side is smooth.
The larger flat prong is the black and the smaller flat prong is the white.
If you have a flat power cord:
Ribbed = neutral or white
Smooth = hot or black
As for the AC lamp working, yea it doesn't matter which wire goes to the lamp it will light even if the wires are hooked up backwards but if you have the Hot which is the black wire and the neutral which is the white wire reversed and the lamp has a metal base and the base was grounded then you could get a shock. That's why sometimes you hear people say they get shocked by touching the metal control panel or coin door. 9 times out of 10 I'll bet some one put a new plug on the end of the AC cord or replaced the cord and reversed the 2 wires. Maybe it's time to read this from Bob Roberts site. Then maybe you will understand how it all works.
Be safe, AC is nothing to mess with if you don't know what you are doing.
http://homearcade.org/BBBB/buildit.html
 
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That's why sometimes you hear people say they get shocked by touching the metal control panel or coin door. 9 times out of 10 I'll bet some one put a new plug on the end of the AC cord or replaced the cord and reversed the 2 wires.

not that case here. many (or even maybe all) AC plugs here are reversible in the way it plugged in to the wall outlet. it contain earth connection, but it reversible between hot and neutral. not like (UK?) plugs with 3 nail goes out.

about people get shocked, that is one of the reason. the other reason, i think, is, they're not using isolation transformer. now, in SEGA simulators cab, they are using a big isolation transformer before distribution point, and the distribution point powers everthing equally, i.e. monitors and smps for the PCB.
 
not that case here. many (or even maybe all) AC plugs here are reversible in the way it plugged in to the wall outlet. it contain earth connection, but it reversible between hot and neutral. not like (UK?) plugs with 3 nail goes out.

Wile that is true you should never reverse the wires and here's why.
The reason that one of the power wires is named "neutral" is because it is connected directly to the building
ground connection at the circuit breaker panel. Therefore it is connected directly to the grounding (third)
wire. In essence, then, two of the three wires at the wall receptacle are actually grounded wires, one being
used for power flow, and the other connected only to exposed metal parts on the equipment. The power
wire that is grounded is called the "neutral" wire because it is not dangerous with respect to exposed metal
parts or plumbing. The "hot" wire gets its name because it is dangerous.
So you don't want to make your metal parts on the game HOT.
Say your ground prong is missing and you wire the game up with the wires reversed. Yes the game will work but all metal parts if connected by a ground strap which they should be will now be HOT so if you touch the metal you get a shock and if you touch it at the same time you also touch a water pipe or Earth ground, your DEAD.
If you wire them up backwards and have a good ground prong on the plug and the AC socket it's wired with a earth ground, many old houses are not then the fuse should blow when you plug it in but hey I could be wrong but that's how it looks to me.
Here's a link that does a good job explaining things.
http://www.apcmedia.com/salestools/SADE-5TNQYQ_R0_EN.pdf
 
no. it's not what i meant. i mean, it is not reversible with purpose. it is the AC plug design that make it possible, that people plug it in in reversed way.

g020529.gif


you see, ours are similar to Europe plug in the picture above. for a solid design like other, it is of course, you won't make any wrong/reversed way in plugging it in.

now, people would say, then you should check every one of them plugged in right by touching metal side of every cab, to make it right. imho, it's not a really good solution. i don't really know, but, using isolation tranformer, looks like solving this problem.
 
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