As the clock ticks towards the end of November, many stores and homes have begun to decorate with Christmas themes to create a more festive atmosphere. In addition to hanging ornaments and glittery ribbons, of course, sparkling Christmas light strings are indispensable. However, some people will find that the light strings at home seem to flicker, and they are not flickering like lights. What is the problem? This time we will look for the cause together and diagnose where the light bulb flickers.
Why do my Christmas light strings flicker at home? Tungsten filament and LED have different symptoms
Some Christmas decorations don’t need to be replaced every year, especially string lights, which you might take off and put away, then take out and reuse next year. Have you noticed that the light strings that worked well before are now starting to flicker? This time I will briefly explain the reasons for both tungsten light strings and LED light strings.
Traditional tungsten Christmas light strings (also known as incandescent lights)
Traditional light bulbs should not flicker if they are in good condition and plugged into a good electrical system. If you have tungsten light bulbs in your Christmas light strings and you notice they are flickering erratically, all you need to do now is unplug them.
When traditional tungsten Christmas light strings flicker, there is a problem somewhere in the system. The most common is that a single strand of wire may be damaged somewhere in the light string. If the flashing rhythm is very irregular, especially in an outdoor environment, it’s more likely that the problem is with the electrical wiring. The symptom you can pay attention to is whether there will be irregular flickering when the wind gently blows the light string and shakes the wires. The flickering will improve when the light string is stationary.
It can also indicate that the electrical system is overloaded because too many wires are plugged into the same circuit, possibly triggering safety measures in the home’s electrical system (such as a popped fuse or a tripped electrical box). Whether we’re talking about a flickering Christmas light string or flickering lights in your home, it’s never a good sign when flickering lights occur, and you should investigate the cause or contact a licensed electrician to help get to the root of the problem.
LED string lights
The situation is slightly different with LED Christmas light strings, and the reason is quite interesting. If your LED Christmas light string is flashing in a very erratic pattern, even switching on and off randomly, or operating in ways you don’t expect, there may be an issue with the string itself or your home’s electrical system, just like the incandescent Christmas light string mentioned above.
On the other hand, if the LED string lights are flashing in a very rhythmic pattern that appears to be flashing quickly but regularly and consistently, then there is nothing wrong with your LED lights. What you’re seeing isn’t a flaw in the wires or bulbs themselves, but the actual frequency of the electrical system. In Taiwan, the AC system that powers homes runs at 60Hz (the US is also 60Hz, China is 50Hz), and some LED lights will actually strobe at 60Hz, which is very fast but still visible to the naked eye, creating a flickering effect.
Not everyone can see or detect flicker, and it’s also worth noting that it’s more easily observed when individual LED bulbs are clustered together. For example, a string of lights along a rafter may be barely noticeable, but the same string of LED lights tightly wrapped around a Christmas wreath will produce a flickering effect that is very intense to the naked eye, mainly due to the different densities of the bulbs.
Why do some string lights flash and others not? Older or cheaper light strings transmit power directly to the bulbs, so they are more prone to AC frequency flickering problems; newer or more expensive light strings have additional components such as bridge rectifiers attached to the wires of the light string, which can convert AC power into DC power and reduce or eliminate the flicker effect in the process.
When purchasing….
If you want to purchase a new LED light string, you can pay attention to whether there are words such as “flicker-free” or “rectifier included” on the packaging or in the product introduction, or check to see if there is a rectifier attached to the wire (usually the plug side is towards the back before the bulb configuration begins). You can also purchase a commercially available rectifier transformer for light strings (which looks like a wire, with a socket on one end and a round connector on the other end) to reduce the flicker of the existing light strings in your home. Plug the power supply of the light string into the rectifier, and then plug the other end of the rectifier into the socket.
Source: KOCPC Chinese