"Standard" bulb base: E26 or E27? Both?

[Jeff Wisnia]

Wikipedia says that they are the same, it just depends on which side of the pond you're on:

Jeff

[k]

I can't seem to find a consistent answer. I see so-called 'standard' bulb bases called both E26 and E27, and I'd really like to know if they are one and the same. The reason? I see fixtures advertised with one or the other type socket. I have googled myself blue, and stood in the lighting dept at Home Depot for half an hour on Sunday. Of course, the kid working lighting that day had no clue.

Bulb packages say things like 'candelabra' base, or 'intermediate' base or 'standard' base, no E26 or E27. Yet, try to buy a fixture on Ebay, and it will require either E26 or E27.

Which is it to be?

tia, Keith

[Jeff Wisnia]

I just reminded myself that when I first moved to Red Sox Nation in the

1950s I discovered that the "standard looking" incandescents used for interior lighting in the subway cars had left handed threads.

DAMHIKT, but they were that way to discourage "bulb snatching".

And they still make them:

Jeff

[k]

Wow, thanks Jeff. I can't tell you how much time I've wasted trying to find that out. I don't yet have wikipedia in my mental list of info sources.

thanks

[DaniRastall]

go there and check out

it says e26/e27 that means the just are call'd diffrent in USA than Europe... :)

had the same problem :D

[AMJAY]

JEFF ,

E 26 AND E27 ARE INTERCHANGEABLE , ACTUALLY E26 AND E27 DENOTES DIAMETER OF BULB FITTING THREAD AS 26 MM AND 27 MM RESPECTIVELY.

E26 BULB ARE USED IN US AND CANADA WHILE E27 ARE USED IN EUROPE.

HOPE I HAVE CLARIFIED.

AMJAY CHANA

[TimR]

In my experience, having lived in both Germany and the US, they are not the same. They are a millimeter different.

E27 bulbs (German) worked fine in our E26 (US) fixtures. But the reverse w as not always true. I have a couple of German lamps that do not reliably t urn on with a US bulb. Sometimes US bulbs fit, sometimes not. The manufac turing variation is apparently enough to allow some but not all US E26 bulb s to work in E27 fixtures. I do not recall ever having an E27 bulb not wor k in an E26 fixture.

Yes, I know bulb is an incorrect term, but I stayed with the terms of this thread.

And yes, I know voltage is different, but that's easily solved.

[Keith]

An E27 socket is probably rated for at least 220VAC that many countries use and certainly would be adequate for the 110VAC in the US. E26 sockets are rated for the lower 110VAC US standard. The diameters of the bulb sockets are 26 and 27 millimeters (for E26 and E27) which are "close enough for government work" (i.e. interchangeable).

[clare]

That strikes me as rather strange, since American bulbs are E26 (small) and Euro bulbs are E27 (large). I could see you having trouble putting E27 Euro 240 bulbs into American E26 sockets - THAT would make sense. And those "american" bulbs would be 120 volts too. An e26 bulb in an E27 socket should go in like butter - but once tightened the threads could ride up a bit, making them a bit ornery about coming back out.

[TimR]

We took American E26 lamps to Germany and bought E27 German bulbs. The power was 240 and 50 Hz. The German bulbs worked fine in the lamps. Of course the plug needed an adapter but those were cheap.

We brought a German E27 lamp back and used it in the US with US E26 bulbs. I cut the plug off and put a US plug on. About half the US E26 bulbs won't work in the German lamp. But apparently there's enough manufacturing variability some of them will.

Here's a good graphic, ignore the text:

[clare]

You need to remember there is basically no such thing as an "american" bulb. They are just about all either Mexican, eastern European or chinese.philipino/vietnamese etc - far east

[clare]

Pitch is the same.

[TimR]

Get your pitch to zero.

Pitch is out, I can't hold altitude.

(For old timers who remember Six Million Dollar Man)

[Mel]

replying to TimR, Mel wrote: Smile. Yes.

[Sarah]

replying to clare, Sarah wrote: E26 (US) are one millimeter shorter and may not make contact with the base. No contact, no light. Longer, E27 bulbs will make contact in the shorter base. I have had the same experience. All my USA purchased lamps worked great in Europe. None of my European lamps or ceiling lights worked in the USA without bulb base adaptors. It has been so long since I purchased them I can't tell you where to go.

[clare]

The 26 and 27 refer to the thread diameter, not length. An E26 will thread all the way into the larger E27 base with no problem, while the larger E27 bulb MAY not thread all the way into the 1mm smaller (nominal) E26 base.

In practice, the precision ov the thread form is so poor there is virtually no perceptible difference in MOST sockets or bulbs. All the Chinese crap is likely E26.5 with a tolerance of +.5 /-0 on the sockets and +0/-.5 on the bulbs.

[Bridget Whitfield]

replying to TimR, Bridget Whitfield wrote: I'm trying to figure out how to get my Led light/bug zapper light bulb to change modes in a e26 fixture. The bulb is supposed to have 3 different modes, mine stays on light & bug zapper all time. There's a mode for just the light & a mode for just the zapper & a mode for both light & zapper. The fixture is in the United States, so I'm assuming it's an e26 & the bulb is a e27 for sure, it's on the pack. How can I fix this? Do they make an adapter that'll fix it, or do I need to somehow change the voltage? Can you please explain to me what I need to do, this is driving me crazy.

[Bridget Whitfield]

replying to TimR, Bridget Whitfield wrote: I'm trying to figure out how to get my Led light/bug zapper light bulb to change modes in a e26 fixture. The bulb is supposed to have 3 different modes, mine stays on light & bug zapper all time. There's a mode for just the light & a mode for just the zapper & a mode for both light & zapper. The fixture is in the United States, so I'm assuming it's an e26 & the bulb is a e27 for sure, it's on the pack. How can I fix this? Do they make an adapter that'll fix it, or do I need to somehow change the voltage? Can you please explain to me what I need to do, this is driving me crazy.

[Randy_M]

replying to k, Randy_M wrote: Read this article:

Contrary to popular belief, the difference is not in the screw diameter but extra electrical insulation provided in E27 as it is designed for higher voltages. Therefore using an E26 bulb in a E27 socket at 240V AC may present safety issues.

[emile]

replying to k, emile wrote: USA: E26, Europe: E27