If a bulb burns out in these mini lights will the string stay lit?

If a bulb burns out in these mini lights will the string stay lit?

Here is a question that I received this morning from a woman in Florida about a string of traditional glass mini lights:

“if I remove one or two bulbs, will all remaining lights stay on?”

That’s a good question, and since it applies to almost all of our mini lights, I thought I’d answer it here in our blog.

All of our mini light bulbs have a tiny shunt wire – you can see it if you look closely – that completes the circuit when a light goes out. So if one light “goes out,” the rest stay on.

If you remove a bulb, however, the circuit is broken, so the rest of the other lights will go out. This is also true if the bulb's base or the socket is damaged.

In a mini light strand of more than 50 lights (this is a rule of thumb), the set will be wired with multiple circuits. So if one bulb is removed, only part of the light strand – a half or a third – will go down. If this happens to you, examine the part of the unlit string and look for unseated or missing bulbs.

If you see a burned-out bulb on your strand, be sure to use a replacement bulb to switch it out. Even though the rest of the bulbs are lit and look fine, they operate at a slightly higher current. In technospeak, mini lights are constant voltage, varying current, and the fewer the bulbs, the higher the current running through the strand. (V=I*R …. if the voltage is constant and the resistance goes down, the current must go up.)

Practically, this means that your light will go out faster. You may have seen this in the past. One light goes out… then another… then suddenly, cascade failure is on your hands. To hold this off for as long as possible, replace those first couple of failures.

Mini lights have a typical lifespan of 1000 to 3000 hours, but the lifespan can be dramatically reduced by heat. If you are using your lights in a semi-closed container, this is a good thing to remember. It’s also good to turn your lights off when not in the room and keep lit bottles and blocks off vintage Steinway pianos.

If you are selling lights as crafts, consider adding a sticker letting customers know these basic rule-of-thumb guidelines.

Hope this quick article helps.

Here is a quick video on the same topic!