Help Hooking up this ISO Transformer

MKplayer1start

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Hey guys,

I got a ISO transformer out of a Sega Indy 500 cab and I need a little help with the wiring.

It looks like the left side of the ISO has 1 Earth Ground, 2 Live, and 2 Neutral (5 wires)

and it outputs to the right side of the iso with Orange, Blue, Blue-white stripe, and Purple. So it looks like it has 2 sets of output these sets are fused so I'm assuming they are the outputs and protected by fuses and either one of these outputs would be safe to connect to my monitor?

Why so many wires coming in and why so many wires going out?

8a5eccc6.jpg
 
That is a transformer, all right, but not necessarily an ISOLATION transformer for use with a monitor. It could simply be a step-down transformer for generating +12 or +5 for coin door lights, PCB boards, etc.

In order to figure it out exactly, you'd need to get a wiring diagram from the game you pulled it from and then check what the inputs and outputs are supposed to be...
 
I'm positive it's for the monitor. The cab has a power supply in it for +12,+5, Ground

I may have to try to find the wiring diagram like you said but I don't think it would be helpfull. I have all the original wiring in the cab and it splits up too many times and it's really hard to figure out what ac power is going to the monitor.

I was hoping I was safe to assume AC input was on the left and the output was on the right. Is it not usually input on the bottom and output out the top?
 
Depends on the iso.

But you made a minor assumption there when you said that you had another PS in the cab for the +5, +12 and ground. THAT power supply is for DC voltage. Some cabs have transformers that output the +5 or +12 AC voltage for coin door lights, lockout coils, etc.

Still, if you KNOW FOR SURE that this is for the monitor, then it should be easy to look in the cab and see what lines coming to the transformer had the AC voltage, and which lines on the other side were going to the monitor.

And that's assuming the monitor in the Sega Indy 500 even required an isolation transformer in the first place. Plenty of newer games with big monitors had newer monitors that did not require isolation, and as a result they did not have isolation transformers in them.

In fact, looking at the Deluxe manual for that game, I'm beginning to think that transformer may be providing power to the steering motor...
 
The monitor is a Nanao MS8-26SU. It is a newer dual res monitor so maybe you're right and it doesn't need a ISO. You really got me wondering now lol

Okay I did a little digging, and it turns out there are two types of these monitors. one is 120v and the other is 100v. If I had a 100v model then this ISO would most likely be to step down the 120v to 100v but looking at the chassis I see both fuses are rated 125V so does this mean my model is 120v? I don't see anywhere else on the chassis that has any voltage information.

I used a multimeter to test the output of the ISO and it does not seem to output AC voltage. instead it seems to output very low DC readings. I tested my AC voltage coming into my cab to make sure I was using the multimeter correct and I get a good AC reading on the power coming into the cab from the wall.

so am I safe to assume I don't need this ISO? it was probably used for the shaker motor in the steering wheel like you said?
 
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It looks like the left side of the ISO has 1 Earth Ground, 2 Live, and 2 Neutral (5 wires)

and it outputs to the right side of the iso with Orange, Blue, Blue-white stripe, and Purple. So it looks like it has 2 sets of output these sets are fused so I'm assuming they are the outputs and protected by fuses and either one of these outputs would be safe to connect to my monitor?

Why so many wires coming in and why so many wires going out?

The answers lie in the wiring diagram: http://arcarc.xmission.com/PDF_Arcade_Manuals_and_Schematics/Indy 500.pdf

It has so many wires coming out because it's not JUST an isolation transformer.

On the input side, it has 1 earth ground, 1 common, and 3 different taps, for different 3 input voltage levels.

On the secondary side, there are two distinct outputs:
1) isolated 100/110VAC for the monitor and motor drive board
2) 12.5VAC for the audio amp board

The manual scan isn't too clear on the labels for wire color. If you have a paper copy of the manual, check it out. Or it would be easy to stick a DMM on each pair to see which is the 12 and which is 110.

Of course, if it's a modern flat screen TV, it probably doesn't need to run off of isolated AC. Doesn't hurt, though.
 
The answers lie in the wiring diagram: http://arcarc.xmission.com/PDF_Arcade_Manuals_and_Schematics/Indy 500.pdf

It has so many wires coming out because it's not JUST an isolation transformer.

On the input side, it has 1 earth ground, 1 common, and 3 different taps, for different 3 input voltage levels.

On the secondary side, there are two distinct outputs:
1) isolated 100/110VAC for the monitor and motor drive board
2) 12.5VAC for the audio amp board

The manual scan isn't too clear on the labels for wire color. If you have a paper copy of the manual, check it out. Or it would be easy to stick a DMM on each pair to see which is the 12 and which is 110.

Of course, if it's a modern flat screen TV, it probably doesn't need to run off of isolated AC. Doesn't hurt, though.

I can confirm on the input side that it has Earth ground, Live, and Neutral coming in. the other 2 wires are not used. That is how it is already wired.

The output I used a DMM and it does not output any AC voltage at all on either output. the only reading I can get out of it is like 0.2 DC

I'm leaning towards this monitor doesn't need a ISO and this ISO is not for the monitor. However I want to make sure I have the 120v model and not the 100v model but there is no label anywhere on this chassis to tell me. I completely removed it to check and was surprised to find no label anywhere. the two fuses on the chassis are 125v though so that makes me think it is the 120v model right?
 
The answers lie in the wiring diagram: http://arcarc.xmission.com/PDF_Arcade_Manuals_and_Schematics/Indy 500.pdf

It has so many wires coming out because it's not JUST an isolation transformer.

On the input side, it has 1 earth ground, 1 common, and 3 different taps, for different 3 input voltage levels.

On the secondary side, there are two distinct outputs:
1) isolated 100/110VAC for the monitor and motor drive board
2) 12.5VAC for the audio amp board

The manual scan isn't too clear on the labels for wire color. If you have a paper copy of the manual, check it out. Or it would be easy to stick a DMM on each pair to see which is the 12 and which is 110.

Of course, if it's a modern flat screen TV, it probably doesn't need to run off of isolated AC. Doesn't hurt, though.

The manual you linked to is for the deluxe which has a larger completely different monitor.

the monitor I have is a Nanao MS8-26SU out of a twin setup.
 
Usually the 100vac versions have a label on the back of the neckboard (and elsewhere) that state it is for 100vac only...
 
The manual you linked to is for the deluxe which has a larger completely different monitor.

the monitor I have is a Nanao MS8-26SU out of a twin setup.

Maybe, but the diagram of the xformer in it matches what you describe and show better. The "twin" schematics don't show any fuses in the secondary circuits, nor the multiple primary taps.

In any case, it's pretty certain that one of the outputs in isolated power for the monitor (and perhaps something else) and for an audio amp.

If your xformer has nothing on the output, then one of two things must be happening:
1) there's no power on supplied to the input side (fuse? breaker? loose/missing connection?)
2) the primary windings are open. Try measuring the resistance (ohms) of the primary side of the xformer (with it unplugged). It'll be a finite reading (and some mega-ohm reading due to your hands touching both test leads doesn't count), unless it's open.

I wouldn't really sweat the 100V/110V/115V thing. All the monitor does with the AC is rectify and filter it to DC, then regulate that down that whatever B+ it needs. Most newer monitors had a pretty wide range of acceptable input voltages anyhow...
 
Maybe, but the diagram of the xformer in it matches what you describe and show better. The "twin" schematics don't show any fuses in the secondary circuits, nor the multiple primary taps.

In any case, it's pretty certain that one of the outputs in isolated power for the monitor (and perhaps something else) and for an audio amp.

If your xformer has nothing on the output, then one of two things must be happening:
1) there's no power on supplied to the input side (fuse? breaker? loose/missing connection?)
2) the primary windings are open. Try measuring the resistance (ohms) of the primary side of the xformer (with it unplugged). It'll be a finite reading (and some mega-ohm reading due to your hands touching both test leads doesn't count), unless it's open.

I wouldn't really sweat the 100V/110V/115V thing. All the monitor does with the AC is rectify and filter it to DC, then regulate that down that whatever B+ it needs. Most newer monitors had a pretty wide range of acceptable input voltages anyhow...

I just checked AC power on the input side of the transformer and it's good. nothing is outputed on the output. Does the monitor have to actually be connected to the output to show a reading? right now I have nothing connected to the output and I'm just touching the wires with my leads.
 
This thing is really pissing me off. I'm ready to yank this whole shit out and put a normal ISO in this thing. Who knows if this monitor needs it or not but it couldn't hurt to have it.

some people say this monitor needs ISO, some people says it doesn't. Wish I knew since I have 3 of these in my garage.

I think I'm done with this. yanking this ISO out and just putting a normal one in there that I know works.
 
take a pic of the monitor chassis, and post it, should easily be able to tell if the chassis has a ISO already on it :)

you will need something to drop the voltages for the naomi sound amp if your going that route, or if you got the ISO for that, then just run the 110v into the sound ISO and that will drop to the correct to go into the sound amp
 
I just checked AC power on the input side of the transformer and it's good. nothing is outputed on the output. Does the monitor have to actually be connected to the output to show a reading? right now I have nothing connected to the output and I'm just touching the wires with my leads.

No connection on the output is required.

Don't just rely on having AC voltage present on the primary side. Unplug it and check the primary side for continuity (resistance, in ohms). The primary winding could be wide open, and you'd still measure 120VAC on the input (because you're applying the 120VAC from the mains)... problem is it's just voltage, there's no current if the winding isn't a complete circuit.

Make sure your DMM is on AC volts (not DC volts), for both input and output measurements.
 
take a pic of the monitor chassis, and post it, should easily be able to tell if the chassis has a ISO already on it :)

you will need something to drop the voltages for the naomi sound amp if your going that route, or if you got the ISO for that, then just run the 110v into the sound ISO and that will drop to the correct to go into the sound amp

647763cd.jpg


Pic is a little dark. Iphone 3GS has no flash...

I have the Naomi sound amp iso so that's no problem there.

I should mention I have one of these monitors running in another indy 500 cab in my garage with no issues. That cab is all setup with a Naomi system and it's working perfect. However, I believe the monitor power is not being Isolated.

This cab I'm working on right now is for me and I was really trying to figure this ISO out
 
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the little yellow box area on the chassis is the ISO transformer so I believe you do not need an additional ISO in the cabinet YMMV (or someone correct if I am wrong)
 
No connection on the output is required.

Don't just rely on having AC voltage present on the primary side. Unplug it and check the primary side for continuity (resistance, in ohms). The primary winding could be wide open, and you'd still measure 120VAC on the input (because you're applying the 120VAC from the mains)... problem is it's just voltage, there's no current if the winding isn't a complete circuit.

Make sure your DMM is on AC volts (not DC volts), for both input and output measurements.

I definately got the DMM on AC setting. That I know. However I don't know how to check for continuity. What setting do I put the DMM on and what do I do with the probes? Put one on Live and one on Neutral with the power off?

I'm no expert in this stuff lol but Understand what you're saying for the most part
 
Okay now I'm really confused. I just put in a different ISO. I had this ISO in my Outrun cab a few weeks ago and I know it works. I hooked it all up and I can't get any AC reading on the output of this ISO either.

It's not my DMM cause it works when I get the reading off the input, and I doubt I have 2 bad ISO's especially since I know this one was working since I last pulled it.

5ee1307a.jpg
 
the little yellow box area on the chassis is the ISO transformer so I believe you do not need an additional ISO in the cabinet YMMV (or someone correct if I am wrong)

Thanks for that Mick. From what you say, and what modessitt has said I'm pretty confident no ISO is needed. I'm also pretty confident I have the 120 Vac model too. so I should be all good.

The problem that's pissing me off is why I can't get any readings on the outputs of 2 ISO's I have now lol it's just bugging me now. I'm gonna go look in my HOTD cab now and test that one
 
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