Are Christmas Lights in Series or Parallel?

Post by raldi » Mon, Dec 15, 2014, 10:30 PM UTC

LeoPanthera wrote: post #7

chillacy wrote: post #6

Earlier quoted context omitted.

Probably to save wire, if you hooked em up in parallel you'd need to send a wire to every bulb from the outlet. With 10 bulbs at 1 inch spacing, you're wiring 1 + 2 + 3 + ... + 9 + 10 = 55 inches of wire instead of 10 Follows a roughly N^2 law

Huh? Why not just use two wires and connect one wire to the other with each bulb. Like this: http://www.planetchristmas.com/Images/MinisA.gif I think the real answer is that if you did it this way (in traditional pre-transformer light sets), each bulb would have to be rated for 120v, or whatever your local line voltage is, which would make them both more expensive, and more dangerous.

Post by [deleted] » Mon, Dec 15, 2014, 10:38 PM UTC

raldi wrote: post #11

LeoPanthera wrote: post #7

Earlier quoted context omitted.

Huh? Why not just use two wires and connect one wire to the other with each bulb. Like this: http://www.planetchristmas.com/Images/MinisA.gif I think the real answer is that if you did it this way (in traditional pre-transformer light sets), each bulb would have to be rated for 120v, or whatever your local line voltage is, which would make them both more expensive, and more dangerous.

Interesting: That would suggest that if you let enough bulbs on a strand go out, you reach a cascading-failure threshold at some point, where the voltage across the remaining filaments is higher than their rating. And then I guess the breaker trips.

Post by [deleted] » Mon, Dec 15, 2014, 10:49 PM UTC

LeoPanthera wrote: post #7

chillacy wrote: post #6

Earlier quoted context omitted.

Probably to save wire, if you hooked em up in parallel you'd need to send a wire to every bulb from the outlet. With 10 bulbs at 1 inch spacing, you're wiring 1 + 2 + 3 + ... + 9 + 10 = 55 inches of wire instead of 10 Follows a roughly N^2 law

Huh? Why not just use two wires and connect one wire to the other with each bulb. Like this: http://www.planetchristmas.com/Images/MinisA.gif I think the real answer is that if you did it this way (in traditional pre-transformer light sets), each bulb would have to be rated for 120v, or whatever your local line voltage is, which would make them both more expensive, and more dangerous.

Post by Sharlin » Mon, Dec 15, 2014, 10:53 PM UTC

vonmoltke wrote: post #12

chillacy wrote: post #6

Earlier quoted context omitted.

Probably to save wire, if you hooked em up in parallel you'd need to send a wire to every bulb from the outlet. With 10 bulbs at 1 inch spacing, you're wiring 1 + 2 + 3 + ... + 9 + 10 = 55 inches of wire instead of 10 Follows a roughly N^2 law

It requires 20 inches of wire in both cases. When connected in parallel, each socket acts as a pass-through to connect the hot and grounded wires to the next socket in the set, in addition to providing power to the bulb. Thus, the sockets are in series but the bulbs are in parallel. This is how electrical wall outlets are wired. The problem is that a parallel connection requires bulbs that can take 120VAC directly. T…

Post by vonmoltke » Mon, Dec 15, 2014, 11:02 PM UTC

raldi wrote: post #11

LeoPanthera wrote: post #7

Earlier quoted context omitted.

Huh? Why not just use two wires and connect one wire to the other with each bulb. Like this: http://www.planetchristmas.com/Images/MinisA.gif I think the real answer is that if you did it this way (in traditional pre-transformer light sets), each bulb would have to be rated for 120v, or whatever your local line voltage is, which would make them both more expensive, and more dangerous.

Interesting: That would suggest that if you let enough bulbs on a strand go out, you reach a cascading-failure threshold at some point, where the voltage across the remaining filaments is higher than their rating. And then I guess the breaker trips.