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I am planning to take my laptop to the USA. The adapter says input voltage is from 100-240V. However the cord connecting the adapter to the plug mentions 2.5A 250V.

AdapterCord

Will the laptop work along with the charger in the US? Will the cord have any issue being connected to a US plug via an adapter?

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    @chx not really, they don't allow consumer electronics questions... – Glorfindel May 10 at 14:14
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    @chx - Probably a bad idea... If EESE doesn't reject it, the person asking the question is going to get a lot of technical detail irrelevant to the layman. – schadjo May 10 at 14:52
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    @chx Disagree: the asker is travelling and "will my electronics work at my destination" is a completely natural thing for a traveller to worry about. – David Richerby May 10 at 15:22
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    Have they even made laptops the past 20 years whose chargers could be used in Europe, but not in the US? (Have they ever made them?) – Abigail May 10 at 15:56
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    @chx even if this question were on topic on a different stack, that doesn't make it off topic here – Kat May 11 at 17:40
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The cord is marked with the maximal voltage the insulation between the wires in it is designed to withstand. It will transmit lower voltages just fine and not be harmed.

It is also marked with the maximal current it can carry before it might begin to overheat and become a fire hazard. Since the cord is rated for 2.5 A and the power supply promises to draw at most 1.6 A, this will be fine too.

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The ONLY relevant thing to check is the label on the power supply. It states "Input 100V-240V, 50/60Hz". Any outlet that provides voltage and frequencies in that range is safe to use.

That covers almost all countries and certainly the US which operates at 120V/60Hz. You may need a passive plug adapter (or travel adapter) since the physcial shape of the outlets is different. See https://www.worldstandards.eu/electricity/plug-voltage-by-country/ for a list per country.

Do not use any type of "transformer" or "AC power converter". While most of these are safe to use, some are not and there is no need for the extra size, weight and cost.

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    That's not the only thing to check. The cord also needs to be able to transport the power, and with a lower voltage the power supply might draw a higher current - most cords are probably fine, and as Henning has answered, it should be fine in this case too. – Henrik May 10 at 14:21
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    The cord comes with the power supply and it would be strange if only one part of the pair was able to handle the amperage of the different systems. 2.5A at 100V is still 250 watts, which a laptop really shouldn't need. – xyious May 10 at 15:34
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    Power supply & cord and sometimes laptop always get certified together as a system, the power supply is just the place where the logo goes. – Hilmar May 10 at 15:36
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    @Hilmar: Is this also true when the line side of the power supply is a standard connector on it? If I were selling something with power bricks I'd want to source cords as a commodity and keep an option open to switch suppliers without re-certifying everything from a blank slate. – Henning Makholm May 10 at 16:25
  • @xyious I frequently see power supplies with cords other than the ones they came with. Thought I've never seen this with such a lower power device, I definitely have seen devices with power cords that were not suitable for their voltage/current levels. – David Schwartz May 10 at 17:56
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The number on the cord is a rating and represents the maximum safe voltage for the cord. It's like automobile tires. If you get an HR-rated tire rated 130 mph, you are allowed to drive slower.

That says nothing about the power supply; for that, you have to check the power supply. You did; it appears to be the typical multi-voltage power supply that'll work anywhere from Japan to the UK, with the right cord or adapter.

That cord looks like an "IEC C5" cord, which is readily available (mail order, at least) with any nation's plug on the other end. You can't necessarily expect to walk into any retail store and find it, especially now that Radio Shack is in decline.

enter image description here

I recommend a local cord instead of those hokey-dokey universal adapters from China, which do not have Underwriter's Laboratories or other NRTL ratings, and teardowns have shown are dreadfully unsafe.

  • Best buy might have them. On the same note, though, some retailers (Walmart for example) sell universal power adapters for laptops (In case you can't find a cord/travel adapter). – xyious May 10 at 18:13
  • And adapters sold at a competent national US retail store should (not guaranteed) have proper UL or other NRTL listing. – Harper May 10 at 18:46
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    @krubo assuming you're asking about the last paragraph, Harper isn't talking about the laptop power brick, but a plug adapter that would have eg an EU socket on one side and US pins on the other to let you plug an EU corded device into a US wall socket (provided the device could work at 120v/60hz too). – Dan Neely May 10 at 21:11
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    @DanNeely Ah, now I understand, thanks! – krubo May 10 at 21:21
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    @PeterCordes That's taken care of by the IEC standard. A device that takes an IEC C5 cord can't draw more than 2.5 amps, and a C5 cord must be good for at least 2.5 amps. (also in North America, UL requires cordage to be minimum 16AWG, and that's good for 10A+. The 2.5A rating on the cord relates to the connector.) – Harper May 12 at 4:28
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You should be fine. The cord between the adapter and the wall doesn't have any sensitive electronics in it; it's just three (or two, but this photograph looks like three) metal conductors. As others have noted, the proposed use will not exceed the limits shown on the cord.

You'll need an adapter plug to be able to plug it in to a US wall socket, though. If it makes your feel better, you could instead buy a whole cord with a US plug at the other end, rated and tested for US house current.

  • Even though the connector at the device end of the cord is standard (and replacement cords certianly exist), I suspect that locating a shop that sells them alone would be rather more involved than picking up a plug adapter at the airport ... – Henning Makholm May 10 at 13:16
  • @HenningMakholm in my experience, yes, that is the case. Plug adapters are much easier to come by. – phoog May 10 at 14:27
  • Good quality, correctly matched plug adapters that maintain a proper eath path on the other hand can be harder to come by :( – Peter Green May 10 at 15:48
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    If this is for a business trip, the local IT support team might have a suitable cord they could give you. On previous business trips, I have done exactly this and then 'neglected' to return the cord afterwards. I now have a selection of power cords - UK, US and European - which will plug in to the power adaptor for my laptop. I now just take the right one with me when I travel. – Nick May 10 at 19:58
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    @Nick That's where all the cables go! – Andrew Leach May 11 at 16:18
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Short answer: Yes. United States AC voltage is 120V 60Hz, which is within the input range specified on the PSU.

Also: Think about it. If they didn't, you would be reading about a lot of fried laptops all the time. Given that laptops are intended to be traveled with, it wouldn't make sense.

  • Just a note: While it may be rated as 120V, it is normally 110V. – Felicia May 13 at 1:00

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