How to choose an appropriate LED

Two days after I hung my string of Hanukah lights, the local squirrels gave it a taste test resulting in about half the string going dark. You might inspect your lights for similar damage. If so, splice or solder the wires back together and it should work. Be sure to use shrink tube or liquid electrical tape for insulation. My 25ft string has about 6 breaks from similar squirrel damage from previous years.

If you plan to fix it, take the time to determine how it's wired. Some possible schematics and wiring diagrams: Trace out your wiring and see what matches.

Try to fix just one section that's currently not lit. If you find it, don't fix it immediately. Use a VOM or DVM to measure the current and you have your answer. Some LED's have built in resistors or current regulators like this:

You can determine which LED is blown in one segment, attach needles to the VOM or DVM leads and probe across each LED by puncturing its wires. If you see an unusually large voltage, the LED that you're straddling is the culprit. Be careful as most light strings do not have any isolation from the AC power line. Use a 117-117VAC isolation transformer or be VERY careful when probing live power.

There's multiple shades of 'white' available; if you can't see the replacements side-by-side, they won't be exact.

Generally available (new stock) LEDs in the same package are likely (for heatsinking reasons) to be electrically compatible. And, cheaper than a set, you can get bags of LEDs from a variety of suppliers, like this:

but polarity, case size, color, are just as mysterious as the 'no manufacturer info available' item you are thinking to rebuild.

Thanks for the help. This is an outdoor display, but I use it indoors. So no animals have chewed on the wires. I dont hasve whole sections out, just two or three bulbs that dont light. I could just leave it alone, but if it's series wired, I know it will eventually overload other bulbs. (Yea, I need to get a better look at the way it's wired). Plus this was a very costly and very pretty display, so I want to keep it in tip-top shape. (Which is why I only use it indoors).

The reason I got this, was because it was a store display, and I got it at a much reduced price. So, running it in the store for weeks probably killed the weak LEDs. However there was no box or instructions. I'm sure it was NOT made in the US, so finding the manufacturer is not gonna help determine the proper bulbs.

Ya know, for someone who is constantly pissing and moaning about "Unreliable Chinese s*it" you sure seem to buy a lot of it.

If they're 5mm LEDs, a bag of mixed random 5mm chinese LEDs would work. Who knows if they'll match on brightness & colour though.

NT