Need help with Jpac and power supply.

[kagem]

Ok, been trying to figure this out by searching and still stumped on a couple of things.  I've decided there are two ways I can hook up a jpac to my jamma cab.  One by keeping the cab's power supply hooked up, and the other by disconnecting the power supply.  I currently have a Power Pro Ultimate Power Supply from Happ installed in the cab.  On the website it says "Requires minimum 1.5 amp load on +5 for proper operation".

I want to do this as cleanly as possible and also have it so that I can easily plug in a jamma board if I wanted to.

Method 1: With Powersupply connected.
I figure I can get away with keeping the voltages hooked up since my jamma connector is keyed so no chance of plugging in the jpac the wrong way.  Also this would keep my coin door lights working (Not entirely sure on that). 

Would removing the voltages be better?  It would be easy for me to do anyway since there is a molex connector in line, but it also includes the grounds connected at A, B, 1, and 2.  Will I have have to add another connector that reconnects the ground wires? 

So my only problem with this method is that I will need to find a way to run a 1.5 amp load on the power supply.  Two things I think that will work are either wire a jamma board to the +5v and ground, or wire a light bulb, but I don't have any idea which will work best.  I figure a light bulb would be easier and I won't have to risk damaging a board, but I don't know what type light bulb will work.

Pros:
Plugging in a jamma board is very easy.
Coin door lights work?

Cons:
Will have to find a way to run 1.5 amp load on the power supply.
Can damage a board if I use one for load on the power supply.
I can lose my mind trying to figure out what type light bulb to use for load.


Method 2: Power Supply disconnected.
What I was going to do is not plug in the AC to the cab's power supply at all, cut up a power supply cord with a three prong plug at the end, then connect the live and neutral to the DPDT switch and the earth ground would go straight to the isolation transformer.  Then from the DPDT switch it would go to the isolation transformer which has both the monitor and marquee light connected to it. 

Biggest problem with this is that for me to plug in a jamma board, I would have to rewire all the connections back to normal, then pull out the whole machine away from the wall and plug back the power supply.  A lot of work, and I do have a board that is not emulated in mame that I would like to be able to play once in awhile. 

One point on this one that I am confused with though is since I don't have the power supply connected at all, where do I get the ground for the jamma connector?  On the ultimarc website it says "Another alternative is to unplug the AC feed to the game board power supply. Ensure that doing this does not also disconnect the ground!"  But doesn't unplugging the AC feed remove the ground from the jamma connector?

Pros:
Don't have to worry about having a load on the PS.


Cons:
Plugging in a jamma board will be a PITA.
coin door lights won't work.
confused about where to get the ground for the jamma connector


Well, if anyone sees if what I'm planning to do is wrong or dangerous, please let me know.  Also if you have any answers or suggestions, they will be GREATLY appreciated.  Thanks.


Oops, almost forgot.  To supply power to the PC and speakers I was planning to cut off the plug of a power strip then connect that between the power supply and isolation transformer (or DPDT switch and isolation transformer if I'm not using the power supply).  Would there be anything wrong with that?  Thanks again!

[SirPeale]

Easiest thing?  Just wire in a switch to the mains power going into the power supply.  When you plug in a board, turn it on.  When you put the J-PAC back on, turn it off.  Dead easy.

[kagem]

If I did it that way, I would still need to rewire it everytime I changed to a jamma board though since the monitor currently get's power from the powersupply.  So when I turn off the switch for the powersupply, the monitor would need to get power from elsewhere, or am I missing something?

[SirPeale]

Oh, you have one of THOSE power supplies.  You didn't mention that.

Ditch that power supply, get a standard Peter Chou supply.  Yeah, you'll have to do some rewiring. 

Here's a good example.

[kagem]

Yeah, right now I'm most likely just not going to use the power supply and rewire the power.  I'm just confused about the part on the ultimarc website where it says:

"Another alternative is to unplug the AC feed to the game board power supply. Ensure that doing this does not also disconnect the ground!"

From how I understand it, if the power supply is no longer being powered or even hooked up to a wall socket then wouldn't that disconnect the ground?  If so, how would I go about reconnecting it?

[SirPeale]

I believe he's talking about earth ground.