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View Full Version : OT: Orientation of Electrical Outlets



Paul Alciatore
09-29-2012, 06:03 PM
Not completely OT as it is for my shop.

Most, if not all duplex outlets are installed in a vertical orientation. My guess is that this is just because the wall studs are vertical and the boxes are nailed or screwed to them. I am going to mount a bunch of outlet boxes on the surface of the wall with the runs to them coming from above. In some cases, I want to run from one box to another by going up again first. Single outlet sized boxes only have one knockout on the end and I would prefer not to take up too much vertical wall space with them so shelves can be adjusted to any desired height.

So, is there any reason why an outlet box and the duplex or other outlet in it can not be installed horizontally? I used to have access to NEC books, but do not at present so I can not look it up. Besides, you would probably have to read the whole thing if you are not familiar with it.

Dr Stan
09-29-2012, 06:08 PM
So, is there any reason why an outlet box and the duplex or other outlet in it can not be installed horizontally? I used to have access to NEC books, but do not at present so I can not look it up. Besides, you would probably have to read the whole thing if you are not familiar with it.

None what so ever as I have both vertically & horizontally oriented outlet boxes in my shop. The inspector did not bat an eye about them.

Just make sure the outlets are pointing away from the wall, not toward it. :rolleyes:

MaxHeadRoom
09-29-2012, 06:43 PM
One reason for the recommended vertical mounting is to mount with the ground pin at the bottom, this in order to allow the ground pin to be in contact longer than the power pins in the case of a accidental disconnect of the plug by downward pressure/weight of the cord etc.
Max.

Bob Ford
09-29-2012, 06:49 PM
If you are using Handy Boxes make sure they are 2 inches deep. Wires coming into the side as you want make it very tight when installing outlets. Look up Wiremold they have raceways that let you install outlets wherever you want, room for the wire so in using the plug you do not inadvertently pinch the wire and cause shorts.

Bob

RussZHC
09-29-2012, 06:52 PM
At work we have one area where the plugs are all horizontal...in some weird way I think it is better (I also suspect the plug locations were to an older code re: spacing/distance between) since if you are pulling on the cord trying to get that last little bit of distance, it is really difficult to actually bend a pin, in the vertical position you are pulling to the side and certainly can bend pins

chipmaker4130
09-29-2012, 06:58 PM
In the upstairs part of my shop all the outlets are horizontal. The whole argument about orientation boils down to personal preference. I know more than one electrician who insist that having the ground prong up is safer because a child can't get a coathanger or penny to rest on and short the power prongs. I tried that for a while, but 90% of appliance and tool cords with 90 deg. plugs will only hang 'down' with the ground prong down.

John Stevenson
09-29-2012, 07:02 PM
We can orient any way we want.

The boxes have 7 knockouts, one either end, 3 on one long side and 2 on the other so you can spin them to suit what you want,

http://www.stevenson-engineers.co.uk/files/dday19.jpg

This is the new power rail I fitted to the recent CNC bench I built. All done in steel conduit, a lot is done nowadays in plasric conduit but I'm old scholl and still have all the threading kit.

MaxHeadRoom
09-29-2012, 07:43 PM
All though the N.A. code does not come down on it one way or the other, at least the copy I have, you will find the majority of new building installations that the ground pin is at the bottom, at least in Canada.
A while ago an inspector tried to get the code changed to come down on the side of ground at the top, this was prompted by a Fast food restaurant employee that dropped a metal tray on an outlet that had a plug in the partial out position and it blew a hole in the side of the tray.
At that time the NEC did not rule for it.
Max.

JoeBean
09-29-2012, 07:57 PM
All though the N.A. code does not come down on it one way or the other, at least the copy I have, you will find the majority of new building installations that the ground pin is at the bottom, at least in Canada. A while ago an inspector tried to get the code changed to come down on the side of ground at the top, this was prompted by a Fast food restaurant employee that dropped a metal tray on an outlet that had a plug in the partial out position and it blew a hole in the side of the tray. At that time the NEC did not rule for it. Max.
There is no North American code as Canada and the US have notable distinctions between codes.



In my area of Canada most new construction has the ground on top, as (from what I understand) it is in the UK, for the reason you mention. I prefer this orientation myself for the same reason, as I've never seen any cases where a connector was bent down enough that the ground would be disconnected but the neutral and hot lines weren't.


In either case, no where in the CEC (which I can confirm as I have the electronic edition) or NEC (according to Wikipedia) does it say anything about orientation. If you're having shelving near the receptacle I'd be more concerned about keeping small metal objects off the shelves than I would be about orientation.

flylo
09-29-2012, 08:07 PM
I'm using these thru out the shop. 4 20A 120V recepts & 1 240V twist lock. Plus 2 resets & cover. https://www.surpluscenter.com/item.asp?catname=&item=11-3306.
All the 3Phase on overhead twist lock cords.

SteveF
09-29-2012, 08:07 PM
In my area of Canada most new construction has the ground on top, as (from what I understand) it is in the UK, for the reason you mention. I prefer this orientation myself for the same reason, as I've never seen any cases where a connector was bent down enough that the ground would be disconnected but the neutral and hot lines weren't.


I don't have the latest copy of the NEC but nothing in article 210 mentions orientation of the box.

As far as up or down of the vertical outlet I've had two personal experiences. Once when I was about 14, reaching down behind the couch to plug in the vacuum and only getting it about half way in when my fingers slipped across the prongs, and getting a rather educational lesson. The other time was when a plug was not fully into the work bench outlet and the carpenter's square fell off the peg board right across the prongs making a really nice flash.

All the outlets I install are ground on top. If I was Paul I'd put the neutral prong on the top.

Steve

Rosco-P
09-29-2012, 08:37 PM
In my area of Canada most new construction has the ground on top, as (from what I understand) it is in the UK, for the reason you mention. I prefer this orientation myself for the same reason, as I've never seen any cases where a connector was bent down enough that the ground would be disconnected but the neutral and hot lines weren't.


Ground on top also provides a little more support for a dangling cord. Common to see ground on top in offices, commercial, light industrial, etc..

dfw5914
09-29-2012, 08:56 PM
I like a surface mounted box with the outlet facing the floor, use hospital grade outlets and the cords wont fall out.

justanengineer
09-29-2012, 09:03 PM
Ive lived in several areas where local code was quite different from the NEC, as IIRC, NEC is typically the minimum state standard. Maybe its just my luck, but everywhere Ive lived has required ground on top. The local electrical inspector here actually came into my new/old house with a negative attitude bc a "homeowner" (me and Dad) rewired everything ourselves from the panel in. His attitude quickly changed beginning with a positive comment about the outlets' orientation.

I would suggest calling the local building inspector. When all is said and done, they are the ones whose opinions matter.

firbikrhd1
09-29-2012, 11:26 PM
I just spoke to a master electrician friend (brother in law) about this the other day. The question arose because lately I've been seeing more outlets with the ground on the top which is unusual where I live. His answer was that the code varies with local regulations. MaxHeadRoom's two posts pretty much say what he told me. Apparently Electrical Engineers get together and attempt to resolve problems that they deem pose extra risk to end users.

Dr Stan
09-29-2012, 11:30 PM
Wonder if it would have made any difference when I stuck a straight blade screwdriver in an outlet when I was two? I still remember the shower of sparks on the hardwood floor. BTW, I have the screwdriver and it has a notch burned in the side of the blade. Mom gave it to me a couple of years before she died.

That could/should also explain a couple of things. :o

Bill736
09-29-2012, 11:54 PM
I recently mounted a 5 foot long power strip on my workbench. After carefully planning the installation, and giving due consideration to the location of the power switch and cord, I mounted the strip with the ground prongs in the " up" position.
The very first time I used the power strip was to plug in a " Kill-a-Watt" wattmeter. Sure enough, with the ground prong in the "up" position, the wattmeter readout is upside down. Darn !

Dr Stan
09-30-2012, 12:25 AM
The very first time I used the power strip was to plug in a " Kill-a-Watt" wattmeter. Sure enough, with the ground prong in the "up" position, the wattmeter readout is upside down. Darn !

Could you put a mirror in front of it? :rolleyes: or I guess learn to stand on your hands?

darryl
09-30-2012, 12:35 AM
When I'm installing an outlet for someone else (replacing one usually) I always ask which orientation they prefer. I give my preference, which is ground prong up. I think it's safer, and it looks 'proper' as well. Any new construction which I have to work in has them down, and almost all outlets I see anywhere are the same. As Bill just said though, things are made to the prong down configuration, whether it's an indicator, or a flat-lay plug, etc.

Paul Alciatore
09-30-2012, 03:54 AM
Thanks for all the answers. It seems to be as I suspected.

As for the ground or neutral up idea, I have been a firm advocate of that for many years. I always specify that or install them that way. If a plug points up well, I just live with it.

Thanks again.

Jon Heron
09-30-2012, 02:28 PM
Wonder if it would have made any difference when I stuck a straight blade screwdriver in an outlet when I was two? I still remember the shower of sparks on the hardwood floor. BTW, I have the screwdriver and it has a notch burned in the side of the blade. Mom gave it to me a couple of years before she died.

That could/should also explain a couple of things. :o

Now in Canada you have to use tamper proof receptacles (https://atlantic.nedco.ca//category.action;jsessionid=683602DD93270B3B369AB6D 7B70FB110.hybris2?categoryCode=TAMPERREC) in residential dwellings. The man trying to save us from ourselves lol!
Cheers,
Jon

TRX
09-30-2012, 11:02 PM
I looked at the page. What makes those receptacles tamper-proof?

darryl
09-30-2012, 11:29 PM
Looks to me like there's a sliding cover in the blade holes. When the grounding pin is inserted, it makes those slide out of the way so the blades can then go in.

Don Young
09-30-2012, 11:30 PM
In residences, duplex outlets were initially installed horizontally in the baseboards. When the three wire outlets first came out we installed them with the ground pin down but, as this and many previous threads have shown, there is no compelling reason or agreement on orientation.

Mike Burch
10-01-2012, 12:38 AM
In New Zealand, double outlets are usually installed horizontally, because that's the way they're made to be fitted. Even single sockets are always installed with the earth pin down. I'm not sure if that's mandatory or not, but I don't recall ever seeing an ordinary domestic socket installed with the earth pin at the top.
Completely off the topic, and not wishing to hi-jack the thread, but a question for Sir John - what's that fitting with a handle on it at the right-hand end of the leadscrew on the Sieg lathe on the bench in your photo? My Sieg has nothing resembling that, and it baffles me.

Weston Bye
10-01-2012, 08:38 AM
It seems that somewhere in the past, some sort of ground-pin-at-the-bottom convention was established or assumed when it comes to wall transformers (wall warts). Though a two-prong device, one of the blades on many of them is wider and can only be plugged in in one direction. Being that the blades are usually located offset, plugging into an inverted outlet causes the transformer to rock away from the wall. An outlet located next to a door or somewhere where the wall vibrates can cause a larger, heavier transformer to eventually unplug itself.

Evan
10-01-2012, 10:25 AM
Ground up sure doesn't work well for heavy power cords. Over the 23 years I worked for Xerox that was always a bone of contention. In many locations 220 would be dropped from the ceiling so the plugs were mounted upside down on the 30 and 50 amp machines. This meant the fat and heavy power cords were plugged in upside down with the cable forming a big unsupported loop above the box and helping to pull the plug out of the socket.

Forestgnome
10-01-2012, 10:39 AM
One reason for the recommended vertical mounting is to mount with the ground pin at the bottom, this in order to allow the ground pin to be in contact longer than the power pins in the case of a accidental disconnect of the plug by downward pressure/weight of the cord etc.
Max.
Funny you should mention that because I was at a hospital one day and noticed all their outlets were upside down. I was thinking the same as you, and was going nuts wondering why in the world they would purposely install them upside down in such a ground-sensitive environment. Then I read they do that so if something conductive drops on top of a loose plug it won't short things out.

jep24601
10-01-2012, 11:43 AM
Wonder if it would have made any difference when I stuck a straight blade screwdriver in an outlet when I was two? I still remember the shower of sparks on the hardwood floor. BTW, I have the screwdriver and it has a notch burned in the side of the blade. Mom gave it to me a couple of years before she died.

Could've been my little brother wrote that. When he was 2 in the UK he stuck a key in the top ground pin socket which lifted the shutter protecting the live and neutral pin sockets and then stuck another key in the live. Sure made him scream loud. Key has a melted notch also.