Most of us have seen the charts showing different voltages and power socket pin configurations for various countries. Some even show what sort of telephone socket is in use. But what of the lamp sockets? My usual assumption is that areas that have been under British influence use B22 and elsewhere uses E27. I have seen some reference to B22 being used in Europe. If so where? Are there any 120V areas using B22? I thought it amusing looking through a US specialty light bulb site seeing what they charge for B22 based 230-250V light bulbs...nearly ten times the cost of what you buy them here for...admittedly if you want to buy a 120V E27 bulb here it's the same thing.
Most of us have seen the charts showing different voltages and power socket pin configurations for various countries. Some even show what sort of telephone socket is in use. But what of the lamp sockets?
The authors of such charts assume that you will buy lightbulbs locally if you need to. In many countries, this is an easier problem to solve than getting a new computer cord, and nearly always cheaper, if indeed the problem ever arises at all. That is not to say I haven't wondered the same thing. It is amazing that we essentially have only two generally common incandescent bulb bases for the whole planet, as opposed to what, eight different receptacles?
What exactly is the difference between E26 and E27? The threads are the same but I believe E27 is a longer base, meaning a European bulb would fit an American socket but the reverse might not be true. I seem to remember a German customer of one of my former employers who brought several lamps over from Germany, and had no problem getting American bulbs to fit. Which Edison-base countries use E26 and which use E27?
I can say with some confidence that Indonesia uses an Edison base, although I don't know which one. I have an oil lamp from Indonesia which uses an old light bulb for the oil reservoir, a bottlecap for the wick holder, and the lid of a candy tin for the base. Since the bulb base is cut in half, I can't match it to an American base.
Mexico uses Edison base. The UK we know, and I forgot to check when I was in France (I wasn't an ElectroGeek back then). That's all the countries I've been to.
I can definitely confirm a (British) E27 lamp fits a US lampholder, I have table lamps I purchased in Ohio, they simply got rewired and earthed (grounded). The lampholders were rated 250v 660w so got reused, saved matching threads
Folks, There are a lot of different types of lampholders. Not only your Incandescents, but you have Halogen Linear, Halogen Single Ended and your smaller Halogen Burners. Not forgetting Fluorescent, Tombstone and all the variations of that theme. It's a mine-field.
I had no idea of the E26 base until I saw mention on the antique light bulb site...they seemed to think it was of different diameter. So, I got out some genuine Yankee light bulbs and some Aussie E27's along with both kinds of holder. Well, I couldn't notice any difference in diameter...both screwed into each others sockets just as loose/tight as they would in the 'correct' ones. What was clearly evident is the US bulbs have a shorter base...with some Aussie E27 sockets the contact at the bottom wasn't made even when fully screwed in. Screwing an Aussie bulb into the US socket leaves more of the thread exposed which could be a shock hazard.