Starting the cabinet all at once. It works! And here's how...

[SirPeale]

My plans to have my ATX power supply come on at all times have been thwarted by the limitations of the motherboard I choose to use.  

Pretty much, the idea was to short pin 14 on the ATX connector to ground, powering the motherboard.

It worked - in part - and only for a second.  I've done some research, and aparently the board doesn't like the timing coming from the PWR_GOOD part of the PS.

So, now I have another nifty idea:  a relay, that triggers a momentary connection, turning the board on.

Likely the power would come from 110V, and *just* activate the connection.  Just brige the gap in the pins.

I, knowing nothing of relays, don't know what to look for.  So I'm asking you saavy people for help.

[rsoandrew]

If I understand correctly, what you're trying to do is rig up a button to turn on your computer.

This shouldn't be a problem and you shouldn't need to hook up a relay. Just connect a momentary contact switch to the spot on your motherboard that the case switch would normally go to. You should have a spot to connect a power switch and a spot for reset.

I'm planning on mounting some arcade buttons high on the side of the cab and using those for the power and reset buttons. You could just go to radio shack and get some cheap momentary contact switches that would work fine.

If I didn't understand your problem, please post again and give a few more details.

[Lilwolf]

My old company buys a little board to do just that... Initially they where going to do a relay, but it wasn't 100% safe (for some reason) so they developed a board that was a little more smart.

Anyway, I think they might be more then how much you want.  I think they have been selling them individual for $25 (which is 10 bucks off getting a smart power switch and then moving your button for your PC to the outside of the cabinet... and having that power your cabinet...

but if your interested, I can get real numbers for you.

[SirPeale]

If I didn't understand your problem, please post again and give a few more details.

You sure didn't.

I'm trying to get everything to power on at once.  I tried rigging a power supply to be 'on' all the time, but the motherboard didn't like the PS being wired that way.  It threw the PWR_GOOD timing all off, and wouldn't boot.

So a relay that simply just bridges the connection of the power pins is what I'm looking for.  When power is applied, it just momentarily bridges the contact between the pins - but doesn't stay on.

The motherboard does not supprt resume after power off, so that's not an option.  And I'm not mounting any additional buttons.

[allroy1975]

I was looking for the same thing when I put a PC in my car for mp3s(cuz who wants to go to the trunk to turn on the PC every time you get in the car).  I know a guy that I work with who's super smart with stuff like that and we found a web page that said how to do it, if this isn't answered by monday, I can get you the answer then.  

Unfortunatly I ended up just running some phone cable to a momentary contact switch on my middle console in my car and I have to push the button after the car is started.  


Allroy

[SirPeale]

I'd appreciate it.

[rsoandrew]

Now I understand.

I think a normally closed timed open (NCTO) relay would work. Of course I looked around on-line and didn't find anything. I guess knowing what you need and finding it are two different things.

So I had two other thoughts. You could build a circuit like this one:
 http://www.aaroncake.net/circuits/relaytim.htm

Or buy a few normally closed relays and cascade enough of them to give you the delay you need when the power kicks in before the one that controls the circuit for the momentary contact switch finally opens. With this type of circuit, the cheaper relay is probably better. Now this assumes your PS won't complain about having the "switch" depressed when it gets power. Otherwise, you'll have to build the circuit.

[Stormy151]

I'm not sure if I understand what you want to do- but they DO make time delay relays. IIRC, they are fairly expensive for such a small part.  The ones I've seen are pretty good size- they have a knob on the top for adjusting how long it stays open/closed, all kinds of time intervals are availiable, and you can set some to delay when the relay is triggered, or when it's released.

Here's a link to some I found on Mouser's site: http://www.mouser.com/?handler=data.listcategory&N=388&Ne=300

[_Iz-]

If I didn't understand your problem, please post again and give a few more details.

You sure didn't.

I'm trying to get everything to power on at once.  I tried rigging a power supply to be 'on' all the time, but the motherboard didn't like the PS being wired that way.  It threw the PWR_GOOD timing all off, and wouldn't boot.

So a relay that simply just bridges the connection of the power pins is what I'm looking for.  When power is applied, it just momentarily bridges the contact between the pins - but doesn't stay on.

The motherboard does not supprt resume after power off, so that's not an option.  And I'm not mounting any additional buttons.

I don't get why you don't hook the powerbutton to the motherboard pins, and plug the computer into the control outlet of the "smart" powerstrips and everything else into the switched sockets of the same powerstrip?

[SirPeale]

I don't get why you don't hook the powerbutton to the motherboard pins, and plug the computer into the control outlet of the "smart" powerstrips and everything else into the switched sockets of the same powerstrip?

I'm looking to turn it on via the original cab switch.  I've attached an image how the cabinet is wired.  No, I won't deviate from this wiring.  It simply can not be this hard to get an ATX power supply.



As for a timed relay, especially one that is normally closed, that would turn on the computer, then turn it off again four seconds later.

What I'm looking for is a device to momentarily bridge the gap between the pins when power is applied.  It does this once, and only once, upon application of power.  It will, of course, repeat this when the cab is powered on again for the next time.

[rsoandrew]

OK, I think this time you didn't understand me.

The timed relay or normally closed relay would be hooked into where you want the momentary contact to occur. Since the relay is normally closed when you apply power, the relay would open and stay open until the power shut off. It would not turn off the computer because the circuit would remain open until you powered off the main switch (simulating the normally open switch) The main problem I forsaw is making sure that the circuit remained closed long enough to get the "turn on" signal. That's why I suggested the timing circuit or stacking a few relays to build a "delay" into the circuit.

Relay position when power off

pc momentary wire 1-----|        |---------------relay ground
                                   |        |
                                   |        |
                                   |        |              
pc momentary wire 2-----|         |--------------relay power


Relay position when power on

pc momentary wire 1-----|        |---------------relay ground
                                        /    |
                                       /     |
                                     /       |              
pc momentary wire 2-----|         |--------------relay power


Note that you can use much heavier relays than you'd actually need. You'll just want to get some that are powerd by either ac voltage or stick a transformer in your cabinet to drive the relay.

[SirPeale]

Ah, now I see.

And you're right...it would have to be tripped by 110VAC.

[rsoandrew]

Actually, I just had another idea. Try getting a NC relay that works on one of power leads from the PC Power supply. Then when the power supply comes up, it would energize the relay and the circuit would open. That way, you know the relay would stay closed until the power supply came up.

I think ATX power supplies have +12v in them. If you figure out which wire that is, you could get away with using a cheap automotive relay (but make sure it has a NC position).

Good luck.  

[SirPeale]

Uh...that definitely wouldn't work.  I want the relay (or circuit, or whatever) to turn on the power supply, not for it to turn on other stuff when it itself is powered.

[rsoandrew]

That's what it would do.

When you provide your cabinet power using your master switch, the power supply (suddenly getting electricity) would sense that the power on button is depressed telling it to start up and provide juice to the motherboard. This is because the because the NC relay is simulating the momentary contact switch (power on) being pushed.

Now if you wire the relay to the power supply output side at the correct voltage for the relay, when the power supply supplied voltage to the motherboard, hard drive, cpu (you get the idea) your tap into one of these lines would get power and send it to the relay.  

The relay would then open because it's normally close and opens when it gets power which would simulate that the power on momentary contact switch was released. The relay would stay open until the power was shut off.

Off course this would all happen virtually simultaneously but it should do what you want.

[SirPeale]

Ah, now I see.

Now I just have to *find* that relay.

[rsoandrew]

How about this one (it's toward the bottom of the page. Sorry no direct link).

http://www.meci.com/default.asp?mode=getitems&category=463
______________________________________
SPST, N.C., 5 VDC coil.
MFG: WABASH
Manufacturer Part Number: 1831-5-1 C1
MECI Part Number: 480-0384
________________________________________

This should fit the bill.

[Dak-ak]

I think what you want to do is have a switch that you press, everything turns on... you press it again, everything turns off?

Right now i have my machine configured so that everything is triggered with the pc power button... not what you were initially thinking, but i believe it will get the job done... what i used was:

1 cheap power strip
1 molex power connector (female that accepts pc power connector)
1 relay that is triggerable with 12v and can switch the load we're planning on using.

I opened up the power strip, and cut one of the rails (the "hot" rail, if memory serves) so that the first power plug was still "always" hot, but the rest were cut off... I removed enough gunk in the 2nd slot with a big pair of dikes so i can shove the relay into that position, and ran two wires out of one of the power jacks (from the 2nd slot) those went to the molex and to the 12v on the computer.  the rail that i cut and removed was replaced by bridging over the relay.  The computer is plugged into the first plug (always hot) the arcade equipment (the acutall plug that used to go to the wall) goes into one of the plugs that is behind the relay.  the 2nd slot on the power strip was rendered useless.

I hope this description made sense.

The idea being is i turn the computer on, and everything powers up.  I turn the computer off, everything turns off.  works good for me.

[SirPeale]

I'm trying to stick to as close to this diagram as I can.  So hacking a power strip won't work for me.

[Dak-ak]

this relay is both triggerable with AC and can switch AC.  If you used it you could isolate the pc from the powersupply on the cab.

[Popcorrin]

Peale I was looking to do the same thing you are.  I get the jist of what rsoandrew is suggesting but I don't see how you can operate the relay off one of the leads of the power supply.  The way I understand it there is no juice to the leads off of the power supply until you release the power button, not when the button is actually depressed.  

[rsoandrew]

Popcorrin-It's kind of confusing (and I'm still only 98% sure that it would work because of timing issues) but a relay that is normally closed doesn

[Popcorrin]

I understand what you are saying and how a relay works.  The only thing I was questioning and I may be mistaken on this is that the power on the computer doesn't become active when you press the power button but rather after you release it.
You close the circuit and then open it.  Once it opens the power comes on.  If I am correct (which is not a sure thing)  the relay will not open because it needs power and to get power it needs to open.   It won't be hard to test and you may already have.

[SirPeale]

I'll have to consult my EE friend about this.

[rsoandrew]

I understand what you are saying and how a relay works.  The only thing I was questioning and I may be mistaken on this is that the power on the computer doesn't become active when you press the power button but rather after you release it.
You close the circuit and then open it.  Once it opens the power comes on.  If I am correct (which is not a sure thing)  the relay will not open because it needs power and to get power it needs to open.   It won't be hard to test and you may already have.

You are correct. I didn't really consider that possibility.

I just simulated this on my home PC (unplugged it and then held the on button while plugging it back in) The PC did not power up until I RELEASED the button. So in order for this to work the relay would have to be connected to the 110v system and couldn't be connected to the pc power supply.

It still might work with a normally closed relay but you'll have to do some experimenting. I would be afraid that it wouldn't stay closed long enough - but it might.

Of course since I was wrong on my other theory, you may not want to listen to me at all. I sure sounded good though.

[rchadd]

heres a way to turn on monitor/amp etc when PC is booted...

http://home.bendcable.com/werstlein/

[SirPeale]

My best friend is an electrical engineer, so I emailed him a link to this thread.  His response:

I've done this before, I think.  You just put a capactitor in place of the power switch.  A largish cap, say 100uF would work great, but make sure the voltage rating is at least 16v.  This makes it so that when you turn the AC power is applied to the PS, the machine automatically turns on.  
Is this what you wanted?

Can someone give this a shot?  I don't have any caps laying around.

[SirPeale]

I asked exactly how it worked, here was his response:

I've tried it.  It works as I have desribed.  Don't forget that a capacitor starts as a short and eventually becomes an open when it is charged.  This will simulate a short pressing of the switch.  Try looking for the cap in an old power supply, you want one of the large-ish (finger diameter) electrolytics.

[Popcorrin]

If I am not mistaken that setup would be the same as holding in the power button on the pc and releasing it once power is supplied to the power supply.  I have tried this on my pc and it doesn't work.  In essence it's the same as using a relay as had been described earlier in the thread.  What we need is a way to close the circuit momentarily.  Something that would create a short one-time pulse when power is first supplied to it.
Then again I could be wrong.  Let me know if you get it to work Peale.

[whammoed]

Heres a little different idea but it is unfortunately motherboard dependent:
Some motherboards have a feature in the bios that allows it to automatically boot after power failure.
That is how I set up my cab.  I have a main power switch for everything in the cab (much like an original arcade machine)  when I flip the switch the computer boots automatically.

[SirPeale]

If I am not mistaken that setup would be the same as holding in the power button on the pc and releasing it once power is supplied to the power supply.  I have tried this on my pc and it doesn't work.  In essence it's the same as using a relay as had been described earlier in the thread.  What we need is a way to close the circuit momentarily.  Something that would create a short one-time pulse when power is first supplied to it.
Then again I could be wrong.  Let me know if you get it to work Peale.

I'll have to see if I can dig up an old PS or something, I don't have any caps lying around.  The was he describes it, it just might work.

[SirPeale]

Heres a little different idea but it is unfortunately motherboard dependent:
Some motherboards have a feature in the bios that allows it to automatically boot after power failure.

As stated above, this board doesn't support this feature.  Otherwise I'd use it, believe me!

[whammoed]

As stated above, this board doesn't support this feature.  Otherwise I'd use it, believe me!

Sorry, scrolled to fast and missed that thread.  New suggestion: get new motherboard    
Geez, im useless!  

[GadgetGeek]

This thread has intrigued me so I did a google on automatic momentary switch and this was one of the hits.  I know it is for a degaussing coil, but some of the logic seems applicable here.

Link

[Ken Layton]

Try an "Interval On" style time delay relay.

[Popcorrin]

Sounds like Ken has a viable solution.
I got to thinking a person could try using 2 relays wired into the power button circuit with one of them being NO and triggered by the 110V AC cab power supply and the other one being NC and being triggered by a 12V lead off of the computer power supply.  

When the cabinet is switched on it would send 110V to the NO relay thus closing the circuit and simulating pressing the power button which in turn would turn on the computer ( I think).  This in turn would cause the NC relay to open which would simulate released the power button.

[danny_galaga]

http://forum.arcadecontrols.com/index.php/topic,58932.msg1377974.html#msg1377974

1/4 scale space invaders project

[danny_galaga]

I forgot to mention the reason an ordinary relay works here is because of inertia. The power may be  on virtually instantaneously (well, the speed of light anyway) but the contacts have to physically overcome the inertia of being closed. Thus there is power available to use before the contacts open. And voila! the computer switches on!

[rampy]

Peale, may I inquire as to why you are so steadfast in not wanting to deviate from the example arcade power wiring diagram (the bob roberts one) but are willing to wire up all sorts of capacitors/relays elsewhere.

I'm just wondering...

I know you know there's ways of accomplishing this (bit strip/sears strip) but why it HAS to be controlled via the original switch is confusing me... why is that your requirement in this case...

You can pretty much do the same thing with a bit strip (if i understand correctly)... you would wire up the cabinet the saw way, BUT you wouldn't mount the toggle switch to turn on the AC mains... (it could still be there, but inside the cabinet... always "ON")... then run two wires from the power switch header on your mobo to a momentary contact switch (or find a momentary contact toggle switch if you are style concious) and mount it where the original power toggle switch was.... plug the pc's AC cable into the sensing part of whatever smart strip you choose... plug everything else, elsewhere on the strip... Badaboom bada bing... single turn on...

*shrug* there are fancy switching devices like those used to power on car pc/mp3 players as mentioned...  I too will try and dig up a link/info for the sake of completeness...

I'm sorry if I misunderstood your requirements, Peale... but I'm not sure why you are making it harder than it needs to be... *shrug*

Good luck!

rampy

EDIT it's not quite what you need, but it's a similiar idea for car mp3 players as mentioned earlier ebay auction for ITPS LDO Car Power Sequencer --- actually never mind...  apples/oranges

EDIT2 -->  If you *HAD* to go the "automagically short the mobo power switch pins" route (besides a tom and jerry-esque contraption that relies on scaring a chicken into laying an egg and coming down a chute...) I bet your EE friend could make a very simple circuit that when the ATX powersupply kicks on because mains are applied to it... could create some sort of 1 time pulse/latching switch thingie... it's been 10 years since I took electronics... but there's gotta be a simple way  to do what you are asking if you have to go that route...  the capacitor trick seems pretty clever, but i wonder if there's a catch.

[maraxle]

I pulled a motherboard out of an old network appliance and used that in my cabinet.  It was a standard ATX motherboard, and lacked the auto-power-on feature, just like yours.  However, who ever made the appliance put this little board on there that snapped onto the 2 rows of pins where the power button, reset button, power led, reset led, and hd led all plug in.  When I have that board attached, it powers itself on.  When I get home, I can pull that little board out and take some pictures of it.  It might have a manufacturer's name on it, or possibly even be easy for you to duplicate.