Comments on: Mystery outlet at O’Hare

By: John V

John V — Thu, 21 Jul 2011 23:43:01 +0000

I too will comment after almost two years without a comment.

I have to fly through O’Hare about eight times a year now. After my last trip through I took a picture of the outlet and figured out it is a NEMA L5-15R receptacle. I bought an L5-15P plug at Home Depot (Pass & Seymour PSL515P) and a 1-foot extension cord (http://www.pchcables.com/1fopoexca.html). Cut the plug end off of the extension cord and attached the L5-15P plug. Hoping to give it a try my next trip through O’Hare.

My guess is they use those outlets for two reasons. To keep the vacuum cleaners from pulling their cords out and also so the people who do the vacuuming don’t have to fight for a receptacle to use with all the travelers :) Pure speculation on my part.

By: Jon Udell

Jon Udell — Mon, 14 Sep 2009 14:58:39 +0000

> Forgive me for commenting on a two-year
> old blog post

No apology needed! One of the delightful aspects of this medium is that it can fold time as well as space.

> Just note that having a voltmeter in your
> carry-on luggage does, in fact, make you
> a big nerd.

Ya think? :-)

> I watched in horror as a fellow passenger
> gleefully shoved her two-prong MacBook
> power plug into that exact receptacle type
> until it “fit”.

Chuckle.

Well the situation at O’Hare seems to be improving but it’s still highly variable on an airport-by-airport basis.

By: Matt

Matt — Mon, 14 Sep 2009 07:36:53 +0000

Forgive me for commenting on a two-year old blog post, but I wanted to add to some of the information in previous posts for anyone else that comes across this (perhaps one of you is in O’Hare reading this blog right now?).

As many other commenters have since suggested, the plug you’re looking at is almost certainly NEMA L5-15, which is essentially the twist-lock version of the same mains power that every household in the US is used to. Even if the receptacle was a strain of L6 (which is rated at 250V), most laptop power adapters today will handle either 120/240V standards without blinking. 240V is in fact safe for almost all modern laptop power supplies, but you should always check the rating on your device before plugging it in. Better yet, if you have a voltmeter, measure the voltage directly before plugging anything into a foreign outlet. Just note that having a voltmeter in your carry-on luggage does, in fact, make you a big nerd.

Also, as an amusing aside, regarding (comment #2) Glenn’s note about these receptacles being effectively idiot-proof… the last time I traveled through O’Hare, I watched in horror as a fellow passenger gleefully shoved her two-prong MacBook power plug into that exact receptacle type until it “fit”. Funny thing is, possible bent prongs aside, the MacBook and the power adapter didn’t seem to mind one bit about the power it was receiving — yet another (anecdotal) clue that the voltage from those outlets does not exceed 240V.

By: R Hayes

R Hayes — Wed, 03 Oct 2007 08:24:25 +0000

Is it possible that you flipped the image (so that it’s the mirror image of the actual socket)? I ask because the radial notch is on the anti-clockwise side of the notched prong, whereas all of the references posted seem to place it on the clockwise side.

By: Larry

Larry — Tue, 02 Oct 2007 13:12:34 +0000

Starbucks compatible twist AC outlets for portable coffee stands that overcook/burn coffee at high prices? Now to figure out why their airport bagels are always stale….

By: Eric Udell

Eric Udell — Mon, 01 Oct 2007 12:53:03 +0000

The standard RV 30A connector is the TT-30, which does not twist lock.
The link from Bret ( comment 12 ) goes to wikipedia right below the section on RV sockets.
Lots of server rooms ( like mine…) use twist-locking sockets like those to try to prevent cords from being accidentally pulled out of the socket. All of my Power Distribution Units ( like an expensive power strip…) have either L5-15, L5-20 or L5-30′s.
I agree, it should be easy to build an adapter, or you can just buy them.

http://www.stayonline.com/detail.aspx?ID=3102

By: All Night Coder - Today’s Top Blog Posts on Programming - Powered by SocialRank

Mon, 01 Oct 2007 12:15:40 +0000

[...] Jon Udell: Mystery outlet at O’Hare [...]

By: Adrian

Adrian — Mon, 01 Oct 2007 06:24:05 +0000

Oooo, scary, 220V.

Got to laugh, only the USA seems to be frightened of the 240-250V standard that the rest of the world seems to use!

By: bret

bret — Sun, 30 Sep 2007 01:18:48 +0000

Jon,
You just needed to check out a different entry on Wikipedia…
http://en.wikipedia.org/wiki/NEMA_connector#Twist-locking_connectors

Doesn’t have to be high-voltage: this could be a standard 120VAC outlet, but using the twist-lock so that when the overnight crew cleans the floors they don’t have to worry about pulling the plug out of the socket. Should be easy to build a connector from a regular 3-prong socket to a twist-lock…

By: Mike

Mike — Sat, 29 Sep 2007 17:33:09 +0000

Give the number of electric carts running around O’Hare,
they are probably dedicated for charging them.
it’s a bit hard to tell from the pix, but it looks like a
30-amp twist-lock. it *might* be a 3-phase 30-amp,
but that’s less likely, unless the charger idea is right.
some large chargers do use 3-phase.

By: Terry Bone

Terry Bone — Sat, 29 Sep 2007 12:41:37 +0000

Those are the same outlets you’d find on the outside of travel trailers to connect up to the main power source and I’d assume like others it is to handle higher voltage/amp.

By: Jon Udell

Jon Udell — Sat, 29 Sep 2007 01:32:10 +0000

“Check these adapters out… the L5-15R that Eric mentions is right I think…”

Tempting. But I think Jess got it right w/respect to airport security.

By: Jon Udell

Jon Udell — Fri, 28 Sep 2007 22:08:19 +0000

This was all very enlightening. Thanks for the excellent comments!

By: Jess

Jess — Fri, 28 Sep 2007 20:46:56 +0000

Every laptop power brick I’ve ever examined has been rated for use at up to 240V (handy because that is standard house mains for most of the world). The amps that a power supply pulls when operating in its rated voltage range is dependent on the power it requires, not on the size of the upstream circuit breaker. You wouldn’t enjoy shorting this power through your body (I can’t say that I’ve enjoyed my experiences with “normal” 110V), but I think you could use it to charge your laptop, given the appropriate adapter. That adapter may not be available for purchase in the USA, because it would inherently defeat the safety features of this type of outlet.

However, the reason that O’Hare has these outlets probably has far more to do with the fact that management doesn’t want you using them. They don’t want people sitting on the floor in that area, they don’t want to provide free power, and they don’t want the janitorial staff to have to evict people from the power outlets. If you do obtain an appropriate adapter, getting caught using it will probably enable airport security to seriously inconvenience you. If you plug into a normal outlet, all they can really do is make you unplug.

By: Richard Querin

Richard Querin — Fri, 28 Sep 2007 19:51:33 +0000

Here Jon,

Check these adapters out… the L5-15R that Eric mentions is right I think…

http://linkpot.net/asphalts

or even better:

http://linkpot.net/hosed