Coin Door Lights - How much power?

[JLR2000]

Ok, I'm wiring the lamps in the coin door up to an old power supply.  I looked up the codes on the lamp and I think this chart shows it as being 6.3 volts ( it's the CEC 259 where the hand is pointing ).


So my question is, should I use the +5 volt  wire or the +12 volt wire from the power supply.  I think the yellow is  +12 and the red is +5.  Anyway, +12 will be really bright, but I'm afraid I'll burn out the bulb quickly.  The +5 will work, a bit dimmer, but I think it will be okay behind the red plastic.  Anyone with any thoughts or been down this road before?  Thanks for your input.

[SirPoonga]

Those bulbs are only rated 6v.  12v will burn them out.

[1UP]

You should be able to use a resistor to drop the voltage.  I'm not sure if there are special considerations for incandescent lights.  I'm using LEDs for all my cabinet lighting (including the coin door) so it's easier to run everything off PC power.  I built a lighting board just for this purpose, using different resistor values depending on what color LED (they use different voltages) I'm using where.  The advantage is that they will not need to be replaced for a long, long time...

[JLR2000]

Thanks for the info guys.  Since most of what 1Up said went over my head (I know very little about electronics, resistors, etc.).  Is there a "dummies" solution for this, i.e. some LEDs that I can get at Radio shack that I can wire directly to the power supply feed?  I don't know anything about how I would put a resistor inline or such.  Don't get me wrong, I don't want to appear to be ungrateful, I just know my experience level isn't up to what 1Up is describing. I guess the safe bet would be to just use the +5volt line and be done with it.

Thanks!

[dhansen]

I use 5v on 6v bulb and it is plenty bright... excuse my grammar...

[MinerAl]

I bought a 12V automotive lightbulb at an auto parts store for less than US$1 and ran it off the +12V (red) lead.

It is BRIGHT, but looks great even in a well lit room.

[Brax]

Since most of what 1Up said went over my head (I know very little about electronics, resistors, etc.).  Is there a "dummies" solution for this, i.e. some LEDs that I can get at Radio shack that I can wire directly to the power supply feed?  I don't know anything about how I would put a resistor inline or such.

Grab a LED from Radio Shack, solder a 640 ohm resistor on the + lead. Wire up the negative and the new positive with resistor to 12 volts on your power supply and you're done.
Every resistor has a flat on it, this shows you the + lead. (If memory serves.... can anyone confirm this?)

LED voltages do differ from around 2.5 volts up to around 5 volts... Most reds are around 2.5 volts. 640 ohms for your resistor is a good all around size for 12 volts.


Oh BTW, the LED's I use on my control panel are bright blues.... They're already 5v so they can be wired directly to the 5v lead on your power supply. That would be the "dummies" solution. I'm not sure if you can find 5v reds...... maybe in the jumbos (which would light up the coin slot nicely)

[1UP]

Thanks for the info guys.  Since most of what 1Up said went over my head (I know very little about electronics, resistors, etc.).  Is there a "dummies" solution for this, i.e. some LEDs that I can get at Radio shack that I can wire directly to the power supply feed?  I don't know anything about how I would put a resistor inline or such.  Don't get me wrong, I don't want to appear to be ungrateful, I just know my experience level isn't up to what 1Up is describing. I guess the safe bet would be to just use the +5volt line and be done with it.

Thanks!

If you want a plug-n-play solution, you'd have to look for 5V LEDs with built-in resistors.  I'm not sure where you can get them, try the RadioShack.com site.  What you really need is high-intensity LEDs, and I don't know if they make those in 5V.  It's very simple to just solder a resistor to one of the LED power lines, I could look it up and tell you exactly which LEDs and resistors I used.  It might be a little more trouble than you want, but once it's done, you'll never have to go searching for bulbs to work in your coin door again.

Okay, here is the exact LED I used: http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CTLG%5F010%5F012%5F002%5F009&product%5Fid=276%2D307  Get 2 of them, get a small circuit board (http://www.radioshack.com/product.asp?catalog%5Fname=CTLG&category%5Fname=CTLG%5F005%5F014%5F003%5F000&product%5Fid=276%2D148) and cut off one of the corners by scoring with a utility knife or x-acto across a row of holes, then snapping off the piece.

Now you need to solder the LEDs to the ends of the circuit boards AWAY from the mounting holes.  You want to have the LEDs sticking up about 1/4" from the boards.  You'll need 2 different colors of wire to hookup the LEDs, so you can tell negative from positive.  Solder your positive wire (red is a good color) to the longer lead of one of the LEDs.  This is easier if you push the wire and the lead into the same hole on the circuit board, then solder them together on the copper side of the board.  Solder a different color wire (black is good) to the shorter (negative) LED lead in the same way.  Now you need to do the same for the other LED and small circuit board.

Finally, you hook the two LEDs together in parallel.  This just means that the positive lead of one LED gets connected to the positive lead on the other LED, and negative to negative.  Now, just solder a 100 ohm resistor (the stripes on a 100 ohm resitor are BROWN-BLACK-BLACK-BLACK) onto the end of your positive wire.  Solder another piece of wire onto the other end of the resistor, and cover the resistor and its leads with some electrical tape or heat shrink tubing.  You can now hook the whole thing up to a PC drive power extension cord inside your computer.  Hook the positive wire to the red wire (+5v) on the extension cord, and the negative wire to the black (ground) wire.  The LEDs now draw power from the PC, and the resistor keeps them from burning out (dropping the 5v power source to 1.7v).



If your coin door is like mine, the light socket is held to the chassis by a bracket and small screw.  Remove the brackets, and screw your circuit boards to the chassis using the board's mounting hole.  Done!

[JLR2000]

Wow, 1Up, thanks for the detailed explanation.  With the links, the photo and the detail, I don't think this is that difficult at all.  I may make a trip to Radio Shack tomorrow to pick up the necessary supplies. Thanks again for the info.

One other question, will these LEDs be brighter, the same as, or dimmer than the 6volt bulb I have running with only 5volts?  Thanks!

[1UP]

Wow, 1Up, thanks for the detailed explanation.  With the links, the photo and the detail, I don't think this is that difficult at all.  I may make a trip to Radio Shack tomorrow to pick up the necessary supplies. Thanks again for the info.

One other question, will these LEDs be brighter, the same as, or dimmer than the 6volt bulb I have running with only 5volts?  Thanks!

No prob.  Actually, I'm a real electronics dummy too, believe it or not!  I can wire positive to negative, but anything more difficult means pulling out the old Radio Shack electronics book, or bugging people here...  Thanks to Carsten Carlos for helping me finally understand how to calculate resistors (even so, I still have to pull out the reference cards to figure out the color codes, and to remember what R=V/I means!   )

[Analog-X]

No prob.  Actually, I'm a real electronics dummy too, believe it or not!  I can wire positive to negative, but anything more difficult means pulling out the old Radio Shack electronics book, or bugging people here...  Thanks to Carsten Carlos for helping me finally understand how to calculate resistors (even so, I still have to pull out the reference cards to figure out the color codes, and to remember what R=V/I means!   )

I dont believe you man!!! Your some kind of a super genious, and being modest.

There are a lot super geniouses lurking around here, their just too modest.  

[Chris]

So my question is, should I use the +5 volt  wire or the +12 volt wire from the power supply.  I think the yellow is  +12 and the red is +5.  Anyway, +12 will be really bright, but I'm afraid I'll burn out the bulb quickly.  The +5 will work, a bit dimmer, but I think it will be okay behind the red plastic.  Anyone with any thoughts or been down this road before?  Thanks for your input.

Use the 5 volt.  I have the same bulbs, and mine light up just fine...

--Chris

[1UP]

So my question is, should I use the +5 volt  wire or the +12 volt wire from the power supply.  I think the yellow is  +12 and the red is +5.  Anyway, +12 will be really bright, but I'm afraid I'll burn out the bulb quickly.  The +5 will work, a bit dimmer, but I think it will be okay behind the red plastic.  Anyone with any thoughts or been down this road before?  Thanks for your input.

Use the 5 volt.  I have the same bulbs, and mine light up just fine...

--Chris

I'm wondering if using a bulb that takes more voltage than can be supplied is like using a device that draws more current than the supply can handle.  In that case, you could end up blowing out your motherboard or power supply.  Or it might just work like using a dimmer switch...  I dunno.

[Chris]

So my question is, should I use the +5 volt  wire or the +12 volt wire from the power supply.  I think the yellow is  +12 and the red is +5.  Anyway, +12 will be really bright, but I'm afraid I'll burn out the bulb quickly.  The +5 will work, a bit dimmer, but I think it will be okay behind the red plastic.  Anyone with any thoughts or been down this road before?  Thanks for your input.

Use the 5 volt.  I have the same bulbs, and mine light up just fine...

--Chris

I'm wondering if using a bulb that takes more voltage than can be supplied is like using a device that draws more current than the supply can handle.  In that case, you could end up blowing out your motherboard or power supply.  Or it might just work like using a dimmer switch...  I dunno.

It's just like using a dimmer switch.

[Ryan]

Just find a 6v adapter at a Salvation Army or second hand store for pratically nothing. Splice the end, wire it to your bulbs, and plug it in.  

[Darkstalker]

Actually, if you REALLY want to get fancy, you can get 12v bulbs on the 12v power circut with a pots dial to control the brightness.  Just remember to hook up your lights in parrallel, NOT in series or your lights are going to get dimmer the further down the chain from the power source you get.  (Go to http://www.geocities.com/SoHo/2003/em3_1.htm for a quick example of the two).  If you're only running the two coin slots, it shouldn't be a big deal to hook them up series since you probably won't notice the brightness difference.

(Quick electonics lesson follows)
Resistor - Drops the amount of voltage in the circut
Pots - Short for Potentiometer <sp>, in short, a variable resister.  Can be adjusted from no resistance (Max voltage) to max resistance (no voltage) by turning the dial.


12v current + 12v bulb = bright bulb
5v current + 12v bulb = dimmer bulb

12v current + 6v bulb = blown out bulb and possible fire hazzard  

[rampy]

heh.. if you wire them in series if one goes out... they ALL go out =P (just like old school christmas lights)

rampy

[hyiu]

I don't really know if its important.... but I would like to share my recent encounter....

I need to buy a transformer for my portable cd player.... and since I want no fuss, I paid the premium and get a radio shack one.... and turns out the current is not up to the spec... (it claims 600mA, but only outputing 300mA) so, I exchange for another one... and after like 3 exchanges, I'm fed up and returned it... (cos they're all bad...) I think the whole batch of their transformers are bad....

when I work on my cab, I need a 12V source for the coin door lights... I have a few old transformers at home... (from old radios and stuffs....) turns out that the 6V one is outputing 9V, and the 12V one is outputing 18V !!!!!

I ended up just using the 6V (outputing 9V) for the 12V bulbs.... so.... if you're feeding anything with those transformers.... you should use a DMM and actually measure what its putting out.... it might be way out of spec....

hope it helps....
         

[Chris]

Silly question, but is it possible that it's the DMM that's flaky?

[Carsten Carlos]

I ended up just using the 6V (outputing 9V) for the 12V bulbs.... so.... if you're feeding anything with those transformers.... you should use a DMM and actually measure what its putting out.... it might be way out of spec....

Hi there!

Problem with cheap transformators is, they are not stabilized. If you don't draw enough current from them, there voltage is far above, which usually doesn't do any harm. Did you measure the 18V when there was nothing connected to the transformator, or where the lamps already on it?
This would happen with every cheap transformator - if you get a stabilized one, you'll always get the right voltage.
DigitalMultiMeters don't tend to get flaky, in mostly all cases you can rely on them.

What I would suggest, why just make things much easier and use the best powersupply you got - get a 4-pin-powerconnector and lead one line from your PC out, I did it this way and so I got perfect 5V and 12V lines in my cab. Your PC powersupply has always enough power left to feed as much lamps as you usually need - and if needed, hundred LED's also!

BTW, thanx 1up for the flowers!   Saw your rotating panel photos, never though that this could turn out that smoothly! Damn, maybe I should think about implementing this in my cab design, too  

[hyiu]

I don't think the DMM is bad.....

but Carsten Carlos is right.... I have no load on the transformer when I measure the voltage....

well.... 1 thing is.... the radio shack ones are definitely bad... cos when I plug it into my cd player... it display "dc low" and will not work.... that means it doesn't have enough juice to work the player......

maybe I just worries too much... but if I see that a 12V transformer can actually output 18V.... I do not want to hook it up to a 12V bulb..... cos if that "load" is not big enough, it won't lower the voltage enough... and it means the bulb will get blown out much faster.... I'm satisfied with the 6-9V source for now....

yeah.... I should have got the power from the computer... but the radio shack I went to doesn't have those 4 pin cables... so... I just stripped an old transformer....

 

[Carsten Carlos]

Well, put the lamp on the transformator and then measure the voltage - I guess this would get you pretty near to the 12V!  

[hyiu]

Sorry... since I've already stripped the 6-9V transformer and the coin door is all wired and I'm already playing... its kinda late to strip the 12V transformer and disconect and connect just for testing....

I do understand what you mean about the load can change the voltage and I do agree... just too lazy to go back... I'm ok with the coin door lights for now....

(cos I'm working on another control panel... heee hee...)

but thx for all the tips !!!...

   

[Ken Layton]

Run the 6 volt bulb from the power supply's 5 volts. Your bulb will light up just fine and will last a long time.

[grafixmonkey]

I dunno if someone mentioned this already (I was kind of skimming) but if you put that bulb between the 5v line and the 12v line it will be 7v, which will give you a little bit more brightness, and it's so close to the bulb's spec voltage I don't think you have to worry about burning out.  Most power supplies only get within a half a volt or so of their target anyway.  (at least that I've measured.)

Just hook the red wire up to one side, and the yellow wire to the other.  Don't use the black ones.  12 - 5 = 7 so you get 7 volts powering your light.