How can I determine voltage of mini Christmas bulbs for replacement in a string?
If the bulbs are wired in series, such that all go out if one of them goes out, you count the number of bulbs and divide that into 120 volts. For example, if the string of lights has 40 bulbs, each bulb is rated at 3 volts. You may have more than one section in the string, especially if it is a longer string of lights. The test is to see how many bulbs go out when you remove one of them. If there are two sections, only half the bulbs will go out. This is the number you divide into 120 volts. It is possible, but not likely, that each bulb is rated at 120 volts. In that case, each bulb will operate independently.
