If parallel, that would mean I would need to run three wires (first get some approved double insulated conductor) and make two splices per every lamp holder. Not really doable, at least I can't imagine how to do it neatly, given both wires go inside the lamp holder which probably is molded plastic.

>Are these sorts of ligth sets always straight parallel wired?
No. Different factories do different things.

It terribly looks like all these bubble light and similar sets are chainable, there are only two wires, that would mean they use straight 120V bulbs.

I wonder if these originally came to be as replacement bulbs to exising E12 light sets.

I could theoretically possibly also run the set on 230 V bulbs, if the bubble can be separated from the light bulb. American wire is rated for 250 V, right?

>>22256
There are lightbulb sets that are chainable but come with an "end of chain" string that completes the circuit. That end piece lacks a female plug on the end to plug in an additional set, because it's the one that loops back.

These are lightbulb sets that when one bulb goes out the entire string of lights goes out. Easiest way to test is to plug them into the wall.

If they end in a female plug and light up, they're wired parallel. If they end in a female plug and don't light up, they're wired in series.

What would a C6 base hint? Some sets with that have arrived in Ebay. The pictures are shit and don't show the whole set so the tell-tale female NEMA plug can't be seen. I asked the seller, but he has not replied.

Wikipedia, everone's favourite reliable source of information, claims C6/E10 was used in "decased old series connected light sets".

>>22262
C6 base should be wired parallel, as they're older or more expensive units than the cheap-ass sets that use series wiring. Series wiring is done because one wire run is continuous while the other is broken up into pieces then connected to lights. Typically cheap sets from the 70s and 80s are series wired, sets from before or after that period are almost always wired parallel.

If you remove any single light from a set and it all goes dark, and all lights up when you reinstall the bulb, it's wired in series.

When sets were put together by hand in third world sweatshops it was cheaper to just have the worker just connect a bunch of short pieces of insulated wire together using the lights to join them, then intertwine the string with the other conductor running the entire length of the set, press them into NEMA connectors and you're done.

These days they're all manufactured by machines, and there's no real advantage to parallel vs. series besides the massively smaller return rate for parallel units.

>>22263
These:

http://www.ebay.co.uk/itm/Vintage-Noma-Christmas-7-String-BUBBLE-LITES-Lights-/112182531954?hash=item1a1e999772:g:8CoAAOSwA3dYEMCE

For future reference: "Noma" bubble lights.

Btw. The series wired sets usually used the kind of bulbs that had that internal shunt thing that would add hot filament's worth of resistance and bypass the broken filament.

Oh the seller told the set uses 110 V bulbs.

>>22264
>The series wired sets usually used the kind of bulbs that had that internal shunt thing that would add hot filament's worth of resistance and bypass the broken filament.
Maybe some did, but my gut reaction is that the cheapest sets don't include any such frills, because I was the redheaded stepchild tasked with putting together working sets of Christmas lights every goddamn year when I was growing up, and those things sure as hell didn't include anything of the sort.

Lately I've been periodically involved with Christmas decorations (more correctly involved when problems arise) and these newer strings are similarly wired in series without any filament. But my workplace is known for buying the cheapest item so they may have found their sets at garage sales for all I know.