Half a strand of christmas lights out series#

They would blow up (literally) if applied to 110 volts AC when they are designed for more like 6 volts DC. LED's operate on Direct Current (DC) and will only light with that current running in one direction. If you try to cut out the fusible links or even replace them with a more serviceable unit, you need to understand something about LED's as opposed to incandescent lights. The fusible links are for safety, not for convenience. That light strand will be out and the rest of the strands will remain lit. If a short or a break occurs in any of the light strands, one or both of the fusible links will blow, are sealed for life, and are not serviceable. At the intersection of the 'legs' and 'rungs' you have a fusible link. The light strand(s) are the rungs with perhaps 20 lights per strand. Imagine a ladder where the legs of the ladder represent each side of a 110 volt circuit.

Half a strand of christmas lights out series#

These strings may well have more than two light series in them, separated by a fusible link on each end of the series. I have never seen light strings with fuses in the plugs will have to look again, but what we DO have is light strings with 'Fusible Links'. Clear light is one of the most expensive. Depending on the element in that matrix, you get different colours. In fact, if the voltage is too high (AC or DC) that space will be violated and the LED will literally 'pop its top'. The polarization of the two poles, and not current flow from one to the otheris what makes that space in between give off light. The large one is the negative side, the small is the positive. See that the two electrodes inside are different sizes. While you are inspecting your defunct string, break into and have a look at an LED. Replacing the fuse or flipping the plug does not address the root problem, and my bet is that you will have to toss the string and buy new. That event likely caused the fuse to blow. The fact that you can replace them should also bring with it the caution that you need to find out what caused the failure in the first place.Ī shorted bulb in one of your strings most likely caused a failure in a diode that changes that 110v AC to DC. The fuse was there to prevent further damage (fires). Testing a bring of LED's would require setting up your multimeter as an ammeter, breaking and testing the light string only (not the other two lines.īecause the string is made to work AS A WHOLE UNIT with AC power, the observation that flipping the plug should alert you that this function has been destroyed. LED's also cannot be tested like an incandescent string of lights using an ohmmeter because they have no filament.

They also need the voltage to be greatly reduced. In order for your LEDs to wok on that circuit they need half of those oscillations to be eliminated. Alternating Current (your house current) fluctuates or oscillates 60 times a second. LED's (Light Emitting Diodes) only work with the current flowing through them in one direction. This business of flipping the plug, using oscilloscopes, or noting hz is all indicative of not understanding Diodes. Has anybody done this to a broken string of LED lights? Is this just a one-shot type of fuse?įailing repairing the 2nd half, I might cut the string in two and just insulate and seal the cut end with heat shrink. Even if I did get the plug open and find the fuse, I'm wondering if the fuse is even some standard size or type that can be readily replaced. The plug at the end with the problem looks like it has a small catch you could push in with a small screwdriver, but it appears almost impossible to pry open the plug without damaging it. Has anybody ever tried repairing this kind of LED Christmas light string? Is it worth it to try replacing the fuse? (Of course, it would only make sense doing so if there wasn't some other more serious fault in the circuit-but how would you debug the cause of the failure?) There must be a fault in the 2nd half of the string, or the fuse in that half must have blown. So, this idea that there are actually two independent circuits seems to make sense to me. I notice that most of the way through the string there are three wires-but at the middle-point of the string, there are only two wires joining the 2 halves. My understanding is that Christmas light strings like these are often two independent circuits, with fuses built into the plugs at either end. The whole string used to work, and it's only about a year or two old. With one string, exactly half of the LEDs don't light up when plugged into the AC. I have a bunch of Noma LED Christmas light strings, each with 70 LEDs. A bit of a low-tech, although seasonal, question for you: