LED polarity

[fertsy]

Is it typical that some bulbs have reversed polarity compared to others or is it just Home Depot's Home Accent (i think that's what they were.) 

I have been making multi colored strands into single color and two green and two red on each strand have a different polarity than the rest. I figured out how to get it to work I was just wondering if all brands were this way.

[budude]

You need to be careful mixing LEDs like that - the Red/Orange/Yellow colors tend to have a lower forward voltage (~2v) than the Blue/Green/White colors which are around 3-3.4v. You may end up blowing up all your Red LEDs and your Blues/Greens will be too dim. The voltages are usually set by resistors (e.g. those blobs on the strings). With incandescents it doesn't matter.

[fertsy]

So far no explosions  Would it happen immediately or something over time? My plans are to take 400 red and put them on one mini tree.

[budude]

It would depend a bit on how many LEDs are inline on the same path. You might see them (Red) be *very* bright - for a while - they may even run that way for a while - but it will definitely shorten their lifespan. Think about a string of 35 LEDs - for Red this would be about a 70v drop while for Blue it might be 112v - that means there would be an additional 42v across the limiting resistor which would somewhere in the area of twice the current for those LEDs (give or take). Do the strings have the inline "blobs" on them? There's a chance you could do some surgery on them and replace the drop resistors with something more appropriate. If anything you may want to do some measurements on a normal string and determine the current draw (probably 15-20mA) and come up with a resistor replacement - it's cheap insurance.