Why Do Some Sections of My Pre-Lit Christmas Tree Not Light Up?

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Discussion Overview

The discussion revolves around troubleshooting issues with a pre-lit Christmas tree where some sections do not light up. Participants explore potential causes and solutions related to the electrical components of the tree, including connectors and bulbs.

Discussion Character

  • Technical explanation
  • Debate/contested

Main Points Raised

  • One participant describes the setup of the tree, including the use of splitters that connect the power to the bulbs, and expresses concern about disassembling these components to troubleshoot the issue.
  • Another participant suggests checking standard causes for string light failures before attempting to open any closed components.
  • A participant proposes using a digital voltmeter (DVM) to check if the bulbs are receiving AC voltage, indicating a method for diagnosing the problem.
  • There is a discussion about the internal structure of the bulbs, noting that one wire glows while another acts as a short circuit, which complicates identifying where the circuit might be broken.
  • Further clarification is provided regarding the function of the anti-fuse within the bulbs, which only connects to the circuit under certain voltage conditions.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the best approach to troubleshoot the issue, with differing opinions on whether to disassemble the splitters or to check for standard failure causes first.

Contextual Notes

Participants express uncertainty about the internal workings of the splitters and bulbs, and there are unresolved questions about the implications of disassembling the components.

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TL;DR
I have a very expensive Christmas tree with two dead branches that drive my wife crazy. Help save my christmas!
I have a Christmas tree that's pre-lit. The basic setup is each section of the tree has power, and a strand of wire that comes out and wraps around the tree. That strand passes through a bunch of green plastic connector things, which appear to be a splitter of some sort - the strand goes in and then out of one end, and on the other end another wire comes out that powers all the bulbs for the branch. The splitters have a little green tab that looks like you are supposed to push it, and then something happens though I have no idea what.

I attached a couple pictures that hopefully illuminate the situation.

So I have two branches out of like, 100 that are dead. My theory is that the connector/splitter things are junky- either it shorted, or disconnected internally, or something. I'm worried about breaking the other 98 branches worth of lights doing anything though. So I guess my question is, can I actually disassemble this green splitter and try to rewire this in a way that isn't a horrible idea? In particular is the little tab actually intended to be a way of assembling/ disassembling, or am I just going to break it trying to push the tab and pull the wires?
 

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I don't know what I'm looking at in those pics.

[ EDIT ]
OK, I see .

1668476148308.png
 
These Christmas string light problems can be frustrating, as you now know.

I would try these two things in order at first:

** [redacted, dumb non-applicable idea]

** use my DVM in AC voltage sense mode to figure out if the bulbs should be getting AC voltage or not. If you don't know how to do that, just ask and we can guide you.
 
I think berk is wise. I'd look a the standard causes for string light failure before opening up closed components.
 
Note: these bulbs have two wires inside, one that glows (and it can burn out) and one (in parallel) that just shorts the circuit. So even if the bulb doesn't light up doesn't mean that's where the circuit is broken (although the working ones definitely don't break the circuit).
 
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Borek said:
one that glows (and it can burn out)
Fuse. The normal voltage across the un-fused bulb is only a few volts.

Borek said:
and one (in parallel) that just shorts the circuit
Anti-fuse. This one is coated with an insulating material that breaks down and shorts once the voltage reaches a suitably high voltage. It is only electrically connected to the circuit once that happens.

BoB
 
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