Why Do Christmas Tree Lights Burn Out

The problem is the shut wire raises the voltage on all the other bulbs because it is a lower resistance than the filament. With higher wattage on the other bulbs, they burn out quicker. The burn out rate will get faster and faster. So it is best to replace any burnt out bulbs as soon as they are discovered.

What causes Christmas tree lights to burn out?

Christmas lights are wired as a “series” of lights along a single electrical path. … When a filament burns out the path is broken – and this burned out bulb in old-style Christmas lights (not modern ones) would therefore stop the passage of electricity to the other bulbs in the system.

How do you find the bad bulb on a Christmas tree?

Simply bring the light tester close to each bulb. The tester’s indicator will light up when it’s near a functioning bulb. If you have a non-contact voltage detector, bring the detector close to the wire section between each bulb to test for voltage. The dead section of wire will be the section after your bad bulb.