Apparently this has been in debate for many years, and my relatively light Google search didn’t find anything conclusive (though I found a SDMB thread that touched on it!)
Half of the receptacles in my NJ home are ground-up and the other half are ground-down.
These days when I replace an outlet, I put the pin on top, because it is easier to plug stuff in by aligning the ground pin first, and because the rare metal thing that drops on a slightly pulled-out plug will hit the ground pin.
So what is the answer in 2011? Is this finally codified, or are we allowed to choose personal preference?
most frequent that i see are ground hole down. it does seem to hold the plug horizontally better.
you may want to orient it so that the cord goes down for right angle plugs that you would use at that receptacle.
in locations where you use metal face plates the ground hole up might be better. also in a workshop area where there are more small metal things that could drop on a not fully inserted plug, the ground hole might be up.
GFI receptacles often have the words printed twice in both directions so that there is always a readable word regardless of which end is up.
The national code (I’ve got the last few years copies right here) says nothing about it as a requirement.
It’s one of the challenge questions I use for electrical contractors - I ask them which orientation the ground should be placed. If they say “code requires X”, then they’re out (and no, my county and city codes are silent on the matter). And if they use the old saw of “it was so nuns wouldn’t electrocute themselves” they’re out.
I’m surprised the orientation of ground hole up isn’t standard based on an incident I witnessed years ago.
After a room was redone for computer equipment, a tech was plugging gear in. At one outlet, just as he was plugging something in, the metal wall plated fell off. (It hadn’t been screwed on.) Fortunately, it hit on the ground prong since it was on top. The tech was pretty surprised (but not shocked!) at that and would have had a big scare if the plate had landed across the two current prongs.
You can imagine a lot of scenarios where a plug is partially out and something conductive falls onto the prongs.
These sort of events have to happen often enough that the people in charge of codes should have noticed and made a suggestion.
The National Electrical Code (NEC) doesn’t specify one way or the other. However, some local codes might. I used to live in a town where the local codes specified the ground hole on the bottom. The local codes in the town just across the river specified the ground hole on the top. You often ended up with dueling electricians over which way was “better”.
From what I’ve seen, most local codes just follow the NEC and don’t specify one way or the other.
Down. I was trained that way as an electrician and I’ve installed them that way for the last 40 years and taught up-and-coming electricians that this is the preferred way. The grounding lug makes contact first no matter which way the outlet is oriented, since the lug is longer than the other two. Additionally, many three-prong plugs have a non-skid surface on the top (two-prong side) of the plug so that your thumb can better grasp the plug. Lastly, if an outlet is old and has become ‘loose’, it’s possible that the plug may sag out of the outlet and self-disconnect; you want the ground to disconnect last. Because of this, and since the writing on GFI outlets is oriented for the grounding lug down, all right-thinking people should immediately change any commie-oriented outlets in their homes.
Seriously, code inspectors will only ding you if you are not consistent in the orientation throughout the project.
The old saw is "nuns bend over to unplug/plug in an appliance, and their rosary beads/cross/whatever touches the hot prong, electrocuting them. I’ve heard it several times before, stated in total seriousness by electricians. Dead nuns tell no tales!
Most of the time, you are looking *down *onto plug and receptacle when plugging it in. When the ground is down, you plug in the ground prong first (which you can easily see between the hot and neutral prongs, since it is wider and longer than the other prongs), and then rotate the plug so the hot and neutral prongs are aligned with their respective receptacles. While rotating the plug, you can easily see the hot and neutral prongs, since they’re on top.
When the ground is up, you plug in the ground prong first (which you can easily since it’s on top), and then rotate the plug so the hot and neutral prongs are aligned with their respective receptacles. The problem is that the plug’s hot and neutral prongs are somewhat hard to see, and it takes a little more effort to align them into their respective receptacles.
I can’t remember any time in my life where I rotated the plug after putting one prong in, unless it was in the dark and I couldn’t see what was where. Why rotate?
I only started going the “ground up” route when I noticed that commercial buildings in my area have been adopting “ground up”, so I figured that they knew more than I did so I would follow.
But many wall warts prefer “ground down” as do many other corded things.
Then again, I have had a piece of metal fall on the exposed ground pin, surprising me because I was a scoffer (yeah right… how often would a piece of metal happen to fall on that plug just so…). I think it was a radio antenna that swung down at the precise moment I was plugging a device in.
The possibility of something falling on the prongs never occurred to me, so I had thought it was arbitrary. Even being arbitrary, though, there’s some value in having them all the same way (people fumbling with plugs will have an easier time if they know in advance which way it’ll be), and since the face convention caught on, I thought that was the semi-official standard.
