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The title is pretty much my entire question. If I order a 240V lamp from Europe that takes removable light bulbs, can I simply use a 120V light bulb? I understand that I would change the plug for a plug-in light, but this particular question is for a hard-wired lamp.

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  • FYI: If you really like the lamp and are willing to modify it, you can but a "light kit" which is basically a socket, electrical cord, and plug. They are usually used to repair an old worn-out socket but you may be able to use it like a conversion kit.
    – Moby Disk
    Commented Jul 15, 2020 at 4:14
  • Any local electrical repair shop worth their salt should be able to convert it properly, if it requires it
    – Caius Jard
    Commented Jul 15, 2020 at 6:58
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    @CaiusJard Do local electrical repair shops even exist anymore? Resocketing a lamp is a DIY job, in any case. It takes five minutes.
    – J...
    Commented Jul 15, 2020 at 13:30
  • Hah, in this throwaway society maybe not so much. Local electrical contractor then.. in any case the impetus for the suggestion was that the OP had to ask in the first place. Plumbing question, not so bad- get it wrong and a few things get wet, but electrics with the demonstrated degree of inexperience (OP hasn't even stated what kind of light it is so I'd say the risk of overloading the internal wiring through lack of appreciation for P=VI is elevated) could be a fire or electrocution waiting to happen and they're a bit harder to walk away from!
    – Caius Jard
    Commented Jul 15, 2020 at 14:22
  • Not an answer, but a word of caution: If this device were to cause a fire or other claimable incident your insurance would not likely cover the costs. Using an appliance other than as certified invalidates the certification.
    – psaxton
    Commented Jul 15, 2020 at 17:53

5 Answers 5

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Hard to say without details. If it is an incandescent lamp with a replaceable screw-in bulb, and the socket fits a bulb made for here and 120V, then yes, it shouldn't matter.

But again, the devil is in the details. If we are discussing screw-in base bulbs, Europeans mainly use E14 and E27 bases. E14 is equivalent to what we in North America call a "medium" base, which is not very common (specialty lamps like aquarium bulbs). We use "candelabra" bases for small bulbs, which is equivalent to an E11, but that is uncommon in Europe. Larger bulbs in Europe are E27 bases. The E number has to do with the width of the base; E27 is 27mm wide. Here in NA we use what's called an "Edison base" and it is 26mm wide, what the EU would call an E26. So it's possible, because of tolerances, for an E27 bulb to screw into an Edison (E26) socket, meaning you can use an EU light bulb in NA fixtures (however the voltage is usually wrong). But going the other way; an Edison (E26) bulb screwed into an EU E27 socket, results in the bulb being loose in the threads and possibly getting jammed, then difficult to remove.

If the lamp has a CFL or LED, then it would depend on whether the "ballast" for the CFL or the "driver" for the LED is able to accept the different voltage. A whole different kettle of fish.

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    If the CFL/LED ballast/driver can handle 120V, does that imply it can handle 60Hz as well?
    – Moby Disk
    Commented Jul 15, 2020 at 4:12
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    Usually, but any modern electronic ballast/driver worth its salt is capable of running multi-voltage. Commented Jul 15, 2020 at 5:02
  • @MobyDisk probably, but it should typically say on the ballast/driver/transformer. Handling multiple frequencies is pretty typical for a transformer like this. I would say more typical than being able to support multiple voltages.
    – Dan
    Commented Jul 15, 2020 at 22:04
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    Most companies making CFL or LED bulbs want to be able to sell the same thing anywhere, so they design the electronic ballasts / drivers to accept a wide range of voltages, and frequencies are irrelevant because they just rectify to DC anyway. But "most" is not ALL, so again, the devil is in the details...
    – JRaef
    Commented Jul 16, 2020 at 4:18
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Answer is that probably you can, but you really shouldn't.

Cables, switches and contacts inside the lamp are rated for specific voltage and current. You can go lower on both, but not higher.

Ampers go up if you want the same power with lower voltage. For example , if your lamp accepts 60 watt light bulb at 240V, then cables etc are rated for 0.25A. Similar 60 watt on 120V would require 0.5A, something cables in the lamp cannot take. You are limited to 30 watt bulbs then. Make sure to replace stickers to prevent mistakes.

Of course, if there are any active components, like electronic switches for touch turning on and off, or brightness controls, these may stop working when undervolted.

If you are buying something exclusive enough you have to import it from another continent, good chance is that you are buying from a small manufacturer. If that's the case, ask them if you can do this, what would be the limits and if they could make a lower voltage version for you.

If you still want to do it yourself, open the lamp to see if there are any active components and what amper limits are there on switches and bulb holders. If you can, you may replace wires for much thicker ones, to be sure. If you will get stuck, or need a specific electrical advice, you should not guess but ask on a sister site Electrical Engineering.

Still, I'd rather recommend buying lamp that simply works with the electrical installation you have.


Bulb sizes are nicely discussed in another answer. Don't screw in a bulb that would be lose.

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    This is a good point, but note that these days there's an easy workaround: use LED bulbs. If instead of a 120V 60W incandescent, you replaced the 240V 60W incandescent with a 120V "60W-equivalent" bulb which actually draws something like 9W, then everything will work fine.
    – Nate S.
    Commented Jul 14, 2020 at 20:10
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    m.leroymerlin.pl/oswietlenie/oswietlenie-stolowe-biurkowe/… 25W @NateS now you have seen two. I can't look for that 10W now as it is 23:00 where I live. Good night :)
    – Mołot
    Commented Jul 14, 2020 at 20:56
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    I disagree on derating the power--at those power levels it's not about what the wires can take, but how much heat the fixture can take. Thus if it's 60W it's still 60W. Commented Jul 15, 2020 at 5:10
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    @Mołot The wire size for chassis wiring at your .5A is 32. For .25A it's 35. The former has a breaking force of 1.8 pounds, the latter .92 pounds. Somehow I don't think they're using wires that fine in a lamp. (And for 1A it's 29 gauge, 3.6 pound breaking force.) Commented Jul 15, 2020 at 20:46
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I bought a really unique ceiling lamp in Dubai a few years ago, and it was set up with E-14 Euro style lamps. They're (barely) available here in Canada in incandescent but short-lived and rather pricey.

Found some nice 4W 120VAC (35 or 40W equivalent) LED 'filament'-look bulbs that fit it and were dimmable (with a proper LED dimmer), bought the set with one spare and it's been working since. Another option was to buy adapters from E-14 to the tiny E-12 base, but I chose not to do that.

The fixture is not approved by CSA or UL but it's properly grounded and running at half the design voltage (and much less heating and current), and is all metal/glass, so it presents negligible risk, in my opinion, and I've seen much worse stuff for sale at big-box stores.

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  • I believe IKEA has E14s. If there’s no UL/CSA, you’re just as good if there’s a TUV, BSI or other other-side-of-the-pond NRTL. The scary one is CE, as it is not an NRTL at all, but for a lamp manufactured and sold in Europe, CE means the EU manufacturer self-certified. Anywhere else it means the manufacturer faked the mark. Commented Jul 15, 2020 at 5:05
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    running at half the design voltage (and much less heating and current) - careful though; fitting a normal 40W 120V bulb would mean double the current and more heating than the 240V 40W bulb the fitting was intended to take. Raising the voltage does not raise the heating - if it did, hundreads of kilovolt/megavolt cross country lines would burst into flames. The actual effect is the opposite
    – Caius Jard
    Commented Jul 15, 2020 at 6:54
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    Yes, it's so much less because the LED bulbs are 1/10 the wattage and thus 1/5 the current (ignoring power factor) at 120VAC compared to the incandescent. Commented Jul 15, 2020 at 6:57
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    @Harper-ReinstateMonica Seems a lot of Asian manufacturers believe CE means "Cheat Europeans". My company routinely has stuff made in China, Taiwan and the Philippines, but invariably we have to send the first couple of batches back as they don't pass muster. They go "You actually WANT us to comply to those rules?". When we insist they get very very nervous and try to renegotiate the contract... Seems their very low prices are suddenly not so low anymore... We expect that now, so we already are prepared for an "initial price" and a higher re-negotiated "real price".
    – Tonny
    Commented Jul 16, 2020 at 9:12
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If dealing with 1" Medium base Edison sockets when manufactured IEC standards, E26 and E27 actually have the same diameter specifications of 26.05 mm (min) to 26.45 mm (max).

The notable difference is that bulbs intended to operate at 120v have a thinner insulator between the tip and the shell, the minimum insulator height for E26 lamps bulbs is 3.25mm and for E27 is 5mm.

So putting a E26 bulb in a E27 socket at 240v could allow an increased arcing risk, but at 120v should not be a problem.

Watts are little more confusing, watts are heat, 3.41 btu's per watt/hour. But is the rating just a limit on the heat the sockets or shades can withstand, or is it a derived number setting the current limit of tiny components? An extreme hypothetical example could be they could make a fixture designed for six 100w bulbs, at 240v that would be less than 3A, so they only need to design internal components for approved for 3A. But if you were to plug in 100W 120v lamps at 120v you would be up to 5A. But in reality you are probably dealing with 3 or less 60W bulbs at 120v, you are only dealing maximum current of 1.5A. Do I think that's an issue? Probably not, but I can't prove it. I could also be concerned I've seen European plugs with built in fuses, the only place I seen plugs like that in the US were on 1970's Christmas lights, there might be some hesitation on my part cutting off a fuse and putting on an unfused plug, into a time delayed 15A circuit without blow characteristics required by lamp maker or approving agency.

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wait we dont have 240 volts in US so when you plug it into the wall it will be a 120 volt lamp am i missing something? does it fit the wall receptacle? need an adapter? adapter doesnt change wall voltage still 120. maybe im the one missing it but not seeing how you could over voltage a US bulb in this scenario. the other point is the light socket size it probably wont fit a US bulb. can buy new sockets at any hardware store not terribly difficult to change. best of luck now I want to see the lamp.

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    So you don't have 240V AC in USA ? Really? You should do some checking.
    – Solar Mike
    Commented May 6 at 7:39
  • OP stated this is a hard-wired light, so plug/adapter is not relevant. Commented May 6 at 14:01

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