LED's & Polarity

FrizzleFried

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I just learned something new today. It seems that LED's care what direction the power runs whereas incandescent bulbs don't. How did I learn this? Well, I purchased a bunch of LEDs and it half of my backboard won't work with the LEDs. After talking with Terry at Pinball Life we determined by backbox is wired with some lamps wired in reverse (power to the lug)... bummer.

Terry says he's heard of some Data East games doing that but never a Xenon or Bally in general.

I wonder what if my box was built by a newb.

:)
 
I just learned something new today. It seems that LED's care what direction the power runs whereas incandescent bulbs don't. How did I learn this? Well, I purchased a bunch of LEDs and it half of my backboard won't work with the LEDs. After talking with Terry at Pinball Life we determined by backbox is wired with some lamps wired in reverse (power to the lug)... bummer.

Terry says he's heard of some Data East games doing that but never a Xenon or Bally in general.

I wonder what if my box was built by a newb.

:)

Weird... but easy enough to fix.
 
I do all my games in LEDS, i love them.

I really dont have to worry about the bulbs going bad.

Ive had the same problem fizzz. Should be a eay fix....good luck
 
That's the difference between the cheaper and the more expensive LED's.

The cheaper ones are just the LED and a resistor. The more expensive ones add an internal rectifier inside the casing, and don't care about polarity at all.

-Hans
 
For clarity, you can't rectify DC. Bipolar LED's are just two LED's connected in opposite directions so they illuminate in either orientation.
 
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For clarity, you can't rectify DC. Bipolar LED's are just two LED's connected in opposite directions so they illuminate in either orientation.

Lots of LEDs intended for pinball do in fact have bridges built in to make them work in either polarity.

DC applied with current flow in either direction to AC inputs of a rectification bridge will give output current flowing in a fixed direction on the DC outputs of the bridge.

EDIT: Assuming a full wave bridge :)
 
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For clarity, you can't rectify DC. Bipolar LED's are just two LED's connected in opposite directions so they illuminate in either orientation.

The Cointaker LED's I've pulled apart so far have a single LED, a resistor and an MB5S rectifier in the casing.

Noflix PLUS LED's, according to their patent, also have an internal rectifier but also add a smoothing capacitor.

-Hans
 
DC applied with current flow in either direction to AC inputs of a rectification bridge will give output current flowing in a fixed direction on the DC outputs of the bridge.

Thanks! I learned something today.
 
I've used Cointaker LEDs in my Jurassic Park. They worked fine. I believe the flashers in this game known to have polarity issues, as well as some other DE games. I know the flashers are rectified as I accidently popped one apart when being a little too forceful with it. Luckily a little work with the sodering iron and some epoxy and all was well.
 
How about the ablaze 555 ones from pinballlife?

http://www.pinballlife.com/index.php?p=product&id=1886&parent=192

Cuz I have had to swap their polarity to work on my BPM and many are not working there no matter if I reverse polarity. Could it be because of one SCR controlling 2 bulbs and one in the chain messing it up?

That BPM thread.

I can pull all of those and put them in my BOP backglass and try a better 555 no prob. Suggestions?
 
I know that older ABLAZE LED's were NOT rectified, I don't know about the current production stuff.

If it says "Non-polarized", that's the ones you want.

-Hans
 
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