Are your outlets installed upside down? (You may be surprised)
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- čas přidán 10. 12. 2022
- In this video I will go over the pros and cons of installing receptacles in different orientations.
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⚡Backyard Maine Sticker give away!!⚡ Please comment on which orientation you install receptacles (or) which way they are installed at your home. Three comment winners will be picked at random on January 1st, 2023. I will reach out to the winners for their mailing address so I can send the stickers to you. Thanks for taking part!
Ground up! Lol
I remember when we started going to grounds up and the arguments made sense. Since then, most of us no longer use metal wall plates so a metal plate falling and shorting is not a serious problem. I do agree that with the ground up, because the ground slot has a tighter grip than the others, it lessens the change of a ground prong on a cord bending or breaking. New projects, I go ground up, except for specific appliances (refrigerators usually) that I know have a cord designed for ground down and they are usually hidden from view so you can't see that they're different from the rest. On existing spaces I match whatever's already there. Being from Chicago where horizontal is the standard, I go horizontal on my own properties. It just looks nicer and cleaner when a recep is parallel with the wall/floor line. I'll never get used to vertical receps.
Thanks for referring me to this video.
This video forgot to mention other orientation specific devices such as chargers and power packs. Virtually all of them are designed for use in a ground down orientation.
@@whiteknightcat Yes there are many devices with 90 degree and some 45 degree plugs that are designed for ground down orientation. The list is long. Also add to the list night lights, plug in scents and even receptacle testers.
As an old electrical dude I have heard the logic of the "ground up" orientation and I do understand it. However; I have never seen a situation where the "ground down" orientation has been a problem, either in residential or industrial applications; and like you say, "ground up" just looks odd. ! Good discussion !
Mostly it is due to how the US plugs are unsafe just as is, compared to say parts of Europe where the contactor has coated sections that are the only part exposed while inserting before the plug reaches the live contactors inside the plug. Where US plugs are immediately life as you insert them, so any exposed metal of the plug is live and if a finger or bit of metal touches them while not flush with the outlet then it is very dangerous. Ground up would prevent falling metal from crossing both live and neutral. It could cross live and ground but then should trip a breaker. That is how an older electrician explained to me why most residential is ground down while industrial applications use ground up. Commercial or office spaces tend to be a 50/50% use case from what I have seen.
Thank you.
The problem with ground up outlets is as the prongs loosen over time the plug starts to sag out of the socket. With the ground down the ground prong supports the plug and keeps it firm.
same here !
Sparks flew during 15 minute band changes from broken guitar strings, etc., during the decade I worked Entertainment Tech crew Resorts International Hotel Casino way back in the previous century.
Of course I screamed like a frightened little girl at first, but you get used to it and it became a rodeo attraction for the audience after that.
"Look how brave those roadies are, flicking away burning metal embers off their P A N T S !"✨
I bought a new house recently and all the receptacles that were linked to a wall switch were upside-down (i.e. had the ground up). The builder told me that's so I can quickly see which switch was activated by the switch on the wall. For more clarification, it was only the top outlet that was controlled, the bottom one was always on. Since you'd normally only be plugging one lamp into that area, it wouldn't make sense to have them both switch activated. Now that I've been here for some time, I like this approach.
I've always used a different color for a switched outlet but I suppose that would drive some people crazy aesthetically, including those who wouldn't bat an eye at seeing outlets oriented two different ways.
@@ziqfriq Color here as well. Makes it much easier. Also use two separate power feeds to all rooms so I can have a live outlet when I throw the breaker to fix a plug.
You are right. In your bedroom you have a duplex receptacle. One is switched and the other is always live. The reason for that is for your lamp is (switched) and your clock is (live). You would not want your clock to go off when you switch the light off.
I wholeheartedly agree with you on ground down. The esthetics are more presentable on a ground down. Many of my cord applications prove that ground down will accommodate other cords more easily.
My thoughts exactly
With ground up, if a penny or other object fell on the pins, there's less than 50% chance of a bright boom. With ground down there's close to 100%. Ground up for the win
Are esthetics or poor cord design more important than safety?
@@presw2pw123 how many of yall just keep your pennies and other conductive objects directly over your outlets that also at the same time happen to be hanging out halfway so that the prongs show enough for it to short it💀 like what is this made up ass scenario lmao
@@presw2pw123 There is no metal in pennies anymore. Maybe that is the real reason they stopped using copper.
As a retired union electrician who for most of my career worked in hospitals, they almost always requested ground up installs. So that's what I tend to lean towards. 🙃
I was Union and did many many hospitals and I never seen that ever . Even notice when you're watching a television or a movie of a hospital room they are down and I also look for the Green Dot just to see if they are hospital compliant on the show or movie
Did you intend for the emoji to be in “ground up” orientation?
So you’re the guy who wired this house Im at now. You’re unique to do that in a house with plastic boxes.
I'm sitting in a hospital lab at the moment. They are almost all horizontal or ground up.
Many appliances, extension cords, etc have wall hugger plugs these days. That's a great feature, unless someone installed the outlet ground up, which means the cord turns up, then folds back 180 degrees to hang down,.
The ground pin is next to the cord, allowing it to hang down flat and close to the wall, UNLESS someone decided it was somehow "fashionable" to put the outlets in upside down with the ground at the top.
The wall hugger cords a re great if the outlet is install CORRECTLY - GROUND DOWN.
For most of my life in the 1900's, I've seen the outlets installed ground down. That's my preference. Also, most of the flat 90 degree plugs are designed so that the cord faces down, when plugged into a ground down outlet. This seems less stressful on a cord, than having the cord facing upward, unless the appliance happens to be above the outlet.
What if the cord is going up to a table and the outlet is below?
@@stevenw4549 Dismount the recepticle, invert it, replace it, and there you go?
@@stevenw4549 I do not see how that matters. If your cord is long enough it will just hang down.
You could do that too.@@timburke4837
I feel the receptacles are happier ground down 😂
I’ve been an electrician almost all my life I’m now retired at 71 years old. When I rebuilt my house in 2006 the NEC wanted ground up so that metal receptacle covers would not short out if it comes loose and falls onto a plug. I couple of years later they changed it back to ground down. Sometime prior to 2006 it was ok to mount the ground down. My house receptacles are all ground up because of when I installed them. Any new receptacles I install they are usually mounted down. The NEC has caused the confusion among electricians. Thanks. Steven B.
The national electrical code updates every three years. I believe it may have mandated ground up in the 2005 code which cause so
many issue that they reverted back in the next cycle. So before and after that version of the code and including the 2023 code today the give no guidance on receptacle orientation so any of the six options would be compliant.
The notes about avoiding Face Up on/under counters was great - that's the nuance that we DIYers sometimes aren't aware of (and I've installed plenty of kitchen and undersink boxes, but never face up!). Thanks for the topic.
Glad you found it helpful.. Thanks for watching.
This happened to me. After my dad passed away, I unplugged the refrigerator to replace a part so Mom would still have a working water dispenser in the freezer door. Dad had replaced all of the switch plates and outlet plates in the house with brass plates. (I always thought they were gaudy.)
Well, Dad didn't screw down the plate for the refrigerator. When I began to wiggle the plug out of the outlet, the brass plate dropped down immediately and landed on the two prongs. I saw a flash of light and heard a "crack" and the power to the outlets in the kitchen went out. The brass plate was scorched. And I don't remember why I was wearing rubber dish gloves, but the fingers on the right glove had scorch marks.
It startled me a bit but what scared me the most was the thought of what could have happened if the breaker hadn't tripped. Those things work INSTANTLY! Thank you to whoever invented circuit breakers!!!
PS: I remember now why I was wearing dish gloves. Refrigerator plugs are hard to get out of the outlet so I put on the gloves to get a better grip.
I think they should make them so the grounds are opposite in each plug, facing inward toward the screw hole. This would allow two transformers to be plugged into each outlet for electronic devices.
Great point.
Why hasn't anybody made a receptacle like this?
If you want two transformer rectifiers then just change the outlet to one with the USB already installed. It makes connections really easy. Or an extension cord with multiple outlets and charging stations. Because you might want more than two.
@@grumpy3543 sure, there are special use outlets available, but there are other transformer uses than just USB. Depending on the form factor of the transformers you might not be able to plug two into one outlet.
Then 90 degree cord ends would have to be redesigned
It was easy to guess what John's preference was going to be, since we had one of his own outlets staring at us through the whole video. Great useful video! Thanks.
I figured some people would pick up on that. lol. Thanks for watching.
LOL. I noticed that right away too.
WGASA?
Thanks for covering this topic. I was asked this question 25 years ago, checked the code but didn't find any definitive answer. It's great to see your thorough review. Regarding safety of electrical convenience outlets, I worked with a group of German engineers 10 years ago and they were concerned that our US receptacle should be recessed like the ones in Europe instead of flush. Seems like a good question.
I've always installed receptacles ground down, unless installing in an area where all receptacles were previously installed ground up. It has always seemed more intuitive to do so for the reasons you mentioned, as well as consistency in orientation when compared to light switches (ground and neutral left, hot right).
well your the one that chooses which is correct so choose wisely🤣🤣
The best way to install receptacles --- if you are doing it for a specific appliance -- is to see if the power cord is a 90 degree cord and orient the receptacle to make sure stress is not on the cord. If nothing specific, I usually do ground down because most plug in wall timers, fragrance generators, like the ground down so when plugged in, the liquid oil doesn't spill out. Yes, there are some now that have a rotating plug built into them. The older ones were in a fixed position I've seen. In the end, install them how you like.
I agree !00 %
I love the installation method of having the receptacle upside down if it’s controlled by a light switch. It makes it so much easier to spot them in a room when setting it up. Hopefully the installer had the best idea of where a switched lamp should go. Sometimes though they don’t get it right and you end up with a switched outlet in a crazy spot. 0:57
Make good sense but I agree it's not always in the right spot.
How would that work when only half the receptacle is switch controlled?
The house I grew up in had a switched outlet. It was right below the switch. How stupid. If you had a lamp there, you could just reach and turn it on.
Some switched outlets are also split with one outlet switched and the other hot all the time. In those outlets it makes sense for the switched outlet to be the bottom outlet, the one that had a lamp plugged in all the time, and the upper outlet to be unswitched.
My house is wired so that the upper receptacle is switch controlled, and the lower receptacle is always powered. So which way should they be installed?
This reminds me of the hotly contested debate on which way the TP should be placed on the holder in the bathroom. It all comes down to user/owner preference. Really impressed you resourced the NFPA's NEC, NEMA and manufactures for guidance as I too used them my entire career.
Growing up in the 80's my mother is and was a master electrician and I still remember going into the laundry room with her to help get the laundry and there was a metal cloths hanger hanging from an electrical plug and was glowing red. She immediatly pushed me out of the room and I remember she grabbed the broom and knocked the cloths hanger off. I remember she went around the entire house and flipped all the recepticles to being ground up. Everytime I've replaced a recepticle in my house I've always put ground up because of this reason.
I've been an electrician for 45 years and I was taught to install receptacles ground down in my apprenticeship. Years later I was working on a breeder reactor at the Savannah River Site which is owned and operated by the U.S. Department of Energy. The DOE specifications at that time were all receptacles be installed ground up for the reason you described in the video.
I'm not an "electrician" but do this kind of stuff quite often. I recently installed a circuit and receptacles in my brother's garage and made them ground up. I was thinking that the ground would help hold the hots in place, but this idea of safety is a good one. Two years ago I completely rewired my house. They are all ground down.😢
Thanks for sharing
National electrical code says to comply with manufacturer recommendation manufacturer shows on every box the proper orientation of the receptacle it always shows ground up the government requires that the military requires that and NASA requires that
@@ds9902 You should know that a picture does not equal manufacturers recommendation. They actually have to recommend in writing. Take a look at Levitons website and notice all the ground down pictures. If they printed top on the receptacle that would be different. You must know this though or we would not be having this discussion. Do you think 85% of the AHJs are getting this wrong?
36 yr licensed electrician here and I always install ground down, I’ve never seen or heard of a fire from this method (Only a short circuit on occasion) and most customers are finally getting used to the polarized plug on the left side so to switch now would only make their lives more complicated and life is already too complicated. 🙂
The electrician that I apprenticed with always did ground down... He said it was because it looked too much like a face. This alone is enough reason to install ground up for me.
Our local building inspector is awesome. I wired my entire addition. Only thing he made me change was to add hardwire smoke detectors in as an upgrade since i had access to exposed walls. In the final he tested all the outlets even the ones i never touched. Well worth the 125 dollars for permit.
I prefer ground up for the reasons you outlined in your video; my wife, however, prefers ground down because it looks better. But, you made some valid reasons for going ground down. My wife will be happy.😂
I'm in Canada, where we have pretty similar electrical codes. The electricians I have discussed this with say that ground up was the original idea, for safety, just like the video explained, however, people just didn't like the looks of it. Most people find ground down to be better looking, so electricians started mounting them ground down because that's what the customers wanted.
and the customers wanted it because degree plugs or wall warts will point the wire up instead of down if the ground pin is at the top!
@@rtel123 Find a nice nightlight for your kids with a nice Disney design on it and plug it into a ground up plug. It will be upside down.
Master Electrician, 30 years.
Down is my preference. Up for switched receptical.
I've never encountered ground up.
@@ericnortan9012 Good idea to let people know which one is the switched one. Thanx for the tip.
I’ve always used ground down installation. However, I think the ground up idea would be in pretty good about preventing a short if somethings fell on the outlet. I also think a ground up is stronger for holding weight up. It gives the positive and negative blade, more leverage strength, whereas if the ground down was used, the ground peg would be a leverage point giving more leverage strength, to pop the two blades out of the outlet.
Just a thought.
I don't care cause I do not try to short out my receptacles with a screw driver while they are plugged in that just seems like to much work for me to do
No, but, children may. That was the main thinking in this idea. It took hold and was never proven to be a failure in any way.@@raven4k998
Don't worry about shorts. That's why we have circuit breakers.
More than leverage I think it's length. Becasue of its length on ground up you are never going to get the cord hanging by a single point. On ground down because of the shorter conductor blades ability to pop out before the ground disengages you can get the cord hanging by ground alone.
Exactly my opinion also
You’re a smart man! I was a Fire Marshal for 25 years with a degree in Fire Safety and Technology and have seen more trouble with ground up than ground down. Could not convince some of our Buildings Inspectors.
Thanks for this video! Every outlet I've seen in my past is ground down, but the 45 year old house I moved into has both. Upstairs, they are all ground up (which just looks wrong to me) and all the outlets downstairs are ground down. The whole thing seems screwy to me so I'm glad there is, at least, some explanation!
I took an electricity for non electricians course as an industrial maintenance mechanic, they suggested ground up because most of our factory cover plates are metal and as mentioned in this video, a short is possible if a loose cover fell on the hot and neutral.
Sure if the plastic that covers the hot and neutral were damaged, then the outlet needs replaced anyway. Beyond that it wouldn't make contact regardless
I've worked for 2 different companies fixing older homes which requires various tools plugged in. It is a mmajor pain in the ass with the ground up loosening the plug, disconnecting the power. The tools and wires are never stationary. It doesn't happen hardly ever with ground down. Two prongs horizontal above do not loosen as much. Therefore it's safer and a more secure connection.
Well Im not a ground down fan boy but I disagree with the reasoning you were taught. It's conceivable to me that the metal plate could fall and rest on the ground pin without touching the ungrounded conductor blade. Then the breaker doesn't trip. That's bad because some hapless fool fiddling with a plug may inadvertently jostle the escutcheon onto the blade and get a quick shock or arc flash before the breaker trips. in that situation with a metal escutcheon that has a high chance of coming into contact with personnel you want it to short out as soon as somethings not right. Definitely ground down with a metal recep cover.
I saw the ground down receptacle behind you as soon as the video started :-) This answered questions about which is the right way I had floating around in my head. Well done, easy to understand, informative and no extra crap or fill, just the facts.
Thank you. I really appreciate that my friend.
I'm glad you said it doesn't matter, because I just finished installing an entire houseful of decora switches and outlets ground-down in a different home. The building I worked in as an employee had them ground-up. Since my own home is ground-down, that's what I went with.
I have been an electrician since 1966 and install outlets in both directions depending one many factors. I primarily installed them ground up it is how I was taught. Back when I first started, metal plates were widely used and ground up was safer. I have also seen many times with ground down outlets , particularly with cheeper outlets, the bottom of the ground hole is broken when the flat prongs work loss and it has tilted down. I alway contend there is no right or wrong way.
Ground up, if horizontal neutral up. While as a county elec. maintenance, there was one building where the office's desk work surface was open towards the wall and had cabinets and a light underneath above the desk. Murphy's law a large paperclip would fall across the blades [ground down], albeit the power cord was not fully inserted by a small amount. This happened 3 times at different workstations. Plus to me is easier
to install, being right-handed, and the position of the ground terminal that I like connecting first. No twisting.
Having dealt with inspectors that wanted the ground to be up in commercial projects due to OSHA rules, and having dealt with several service calls that involved metal parts contacting the conductors on plugs that were slightly loose in receptacles, I am firmly in the ground up installation camp. One was a set of keys, one was an aluminum clipboard, one was a set of tweezers, and one was a pair of metallic rimmed glasses. The main issue with the ground being down is that a metallic object could make contact with just the hot but not the neutral just by being slightly tilted, and so become and remain energized. When a person tries to remove the energized object while connected to ground through touching some other grounded surface, and if the circuit is without ground fault protection, the person will have no protection other than the breaker that will allow a lethal dose of current to flow through a person well before tripping.
If the ground is up, there is a much higher likelihood of the metallic object connecting to the ground pin first before either connecting to the grounded neutral or the ungrounded hot conductor. It is far less likely for a metallic object to connect only to the hot conductor if the ground is up, and more likely to create a short between the grounding conductor and the ungrounded conductor that will allow the breaker to clear the fault without endangering personnel.
I have also found that in my own shop that ground up receptacles also prevent damage to electrical cords, since the cord plug does not pull out and bend and damage the ground connector.
All great arguments.. I'm retired now but I was the senior electrical engineer for a multi billion dollar semiconductor manufacturing facility. We installed ground down on everything and during my 22 years there we never had a fault where something came in contact with a partially plugged in cord. Also never had an issue with OSHA due to the orientation. I am certainly not saying it's impossible though or that you didn't experience these shorts. I think if these types of cults were common the code would be changed. Thanks for your well delivered input.
I agree. But mostly for shop use ground up. There are a ton of variables in a shop that can cause a direct short via 2 electrodes crossing power. The ground on top is an excellent concept.
It is a silly debate, we should fix the actual problem why are outlet plugs designed in such a way that they are live and hot when they are not fully plugged in. They should be designed in such a way that it is impossible to cause a spark intentionally.
@MegaLokopo how about a mandatory plug condom!
Umm, I just realized the impact of what I said. Oh shit! Again! Oh shit! Again!
@@MegaLokopo yeah, how about an internal switch/detector that knows when the last 1/16 is pushed in.
My Dad, a master electrician in Miami and St. Augustine Florida, taught me that it's ground down. For two reasons. The ground is the longest prong and therefore, the last one to disconnect in a partial pull out. That way the appliance remains grounded continuously until the plug is completely removed. I think he was correct.
That's not enitrely true. Its an intuitive thought yes but, the longer length of the ground prevents the shorter conductor blades from breaking contact before the ground pin. That's it's design.
maybe if installed upside down.@@flyingsodwai1382
Rule 1: Ground should contact first and break last. When someone steps on a cable with a "rubber" molded plug and bends the pins ground down give a better chance of obeying rule #1.
Exactly@@ronborthwick1145
That is the first logical opinion I've read/heard... But when actually insertin or removing a plug the ground will be first/last to make/break contact. Any plug that works it's way out of a receptacle due to wrangling the cord would be damaged or very deformed before a ground fault condition could occur. End user ignorance can't be specified or solved by design... That is why we have lockouts... 😂
The patent for the grounded outlet calls it a U ground. (remember there was no ground in the bad old days). This means the ground hole looks like a U when it is installed properly. The patent drawing also shows the outlet with the ground up. As an electrician myself for 40 years, I was always told the reason was because all the wall plates were brass and obviously it would reduce the chance of short circuit should the plate come loose and fall. As stated in the video, it really has become a personal preference. My preference is up.
The metal plate that you mentioned was the reason my college professor taught us to install ground up.
During my career as a journeyman electrician, I installed outlets in whatever orientation my boss or the job specks required.
Happily retired now, so it's not an issue for me anymore.
@@ericcox6764
Ground up/down is a silly question !! Where does one go to college to learn to be "an electrician" ??? Much more important !! ;o)
@pappabob29 Central Kentucky Technological College, located in Lexington Kentucky.
They offered programs that trained folks to become electricians, plumbers, carpenter, and HVAC techs.
3 years after I graduated, they offered me a teaching position.
I'm sure that there are many such schools located in the United States.
Hi, thanks for the video. I became an electrician after working on car & trucks for over 30 years. I worked as a comercial electrician, many jobs were state or federal scale and learned this was controled by the job forman.
Well, you're good for your word. I noticed the receptacles behind you are all ground down. While admittedly the rankest of DIYers, I've always preferred installing receptacles ground down. The electricity seems happier, and if the job doesn't smoke or spark, I'm happy.
Yes, I was thinking that most people were going to figure it out looking over my shoulder.. lol Thanks for watching.
*On my new home, I am specifying sideways,* with the neutral on the top. This places the hot on the bottom, protected by the neutral and ground pins. This also separates the power cords going to the floor to be side by side instead of stacked over each other.
NOW THIS IS A GREAT IDEA. I NEVER THOUGHT OF BUT MAKES MORE SENSE THAT ANY OTHER WAY
I have been an electrician for 25years and I always put my horizontal receptacles with the neutral up for that exact reason.
This to me not only is more pleasing to look at but if you look at a lot of REALLY old homes it was done like this along the baseboards and just was beautiful!
I THINK Eaton makes a model with that orientation.
That is an option of course. Chicago requires receptacles to be run horizontal but the also require conduit to be run inside of the walls of residential construction.
Great video, thanks. Well after been an electrician for 52 years in the Washington, DC/Maryland and Virginia area. I always place the ground down on 15 and 20 amp. circuits.......now if it is,.... 220 volts and large amperage 30-60 amp. I put the ground up because most larger cords have the ground at the top with the cord hanging down.
I like the point you make about ground-up for switched outlets. If for no other reason than to identify the circuit, this makes the most sense to me.
I built my house with all ground up. Over the years a number of them have been reversed to accommodate night lights, lay-flat extension cords and other orientation specific devices.
The better night lights have a base that can be rotated to accommodate up, down, right, or left. :)
Curious to know your logic for installing ground up when ground down is the norm.
Being an electrician and understanding the various arguments I also tried to go ground up in my house. I was married though and wifey said NOPE.
There's something I heard back in the 70's about ground-up plugs being better around young children, simply because it makes them look less like a face, and so decreases toddlers' temptation to mess with them or even to stick something in them.
That's what we were told on Government jobs, but then we would have to go back and turn them ground down because things like nightlights and air fresheners would be upside down otherwise. That's how stupid Government contracts are.
Stuck my curious finger into a hot light socket once as a child.Only once.
As a toddler I did just that with a butter knife. My parents said the jolt knocked me half way across the room.
Sounds like something made up. The only way to protect kids is to have tamper protected receptacles.
I read some psychology research that suggested we prefer ground down for that reason. Humans are programmed to respond to faces both for social reasons and survival.
Ground down everywhere residential and commercial.
Great video 100 dead on no biases.
One more thing to add every receptacle tester i have seen has the "cheat sheet and GFCI test button in the orientation for a ground down application.....
Hi, I agree with you on "Up or Down". I have all of mine down except 1 wall receptacle on the left side of my bench because I have some storage bins on that side where I store screws, nuts, and washers. I just feel that if they should happen to fall over and nock the cord loose for my charger there is less chance of it shorting out.
In Australia our sockets have ground down and are always switched . The switch has a red mark on it which shows when the switch is on. Our active and neutral pins on our plugs have 8mm of insulation on them to prevent shorts like you show at the end of your presentation. (which i found very well done!)
In UK, we have square plugs with a cord that drops down from the plug. Ground is always on top with live and neutral under it.
@@saty580 I don't know about the Australian plugs but the UK plugs are well thought out. The north american stuff is pretty bad. Quite a lot of old houses probably don't have ground if the outlet is 3 prong or the outlet is simply 2 prong.
@@louistournas120 I agree. I grew up in London and now live in Massachusetts USA. Our house was rewired before we bought it. All wall sockets were 3 pin with ground.
Newer US 3 pin sockets require the ground pin to be inserted to lift a gate covering the live and neutral holes. Older ones like ours allow a 2 pin extension cord to be used (no ground for the extension and the attached device).
A metal chain fell behind my daughter's desk and shorted live to the higher ground. It sparked until the fuse box circuit breaker flipped. If ground had been down, it would only have flipped the circuit if too much current flew.
Live and neutral pins are different sizes with the idea that live from wall to switch is short and when off, the attached device and return are at neutral (0v).
For the case of side exit cord plugs, the ground UP works for a power board or appliance on a desk where the socket-outlet is under the desk or in a laundry where the dryer is above the washing machine.
Thanks for bringing this subject up. Needs discussion, but IMO I believe that ground up certainly dictates a need for plugs to either be rotational, or manufacturers need to offer 3 prong extension cords made with corresponding plugs for ground up…as your video clearly shows.
Switch controlled outlet = 1/2 hot as generally only half (or one set of openings) are switch controlled so you have a constant hot on the other set :) Former Sparky here who knows that ground down seems the auto standard that is taught! (even after my journeyman explained what you did about an arc across the 2 poles). Love your videos as most are neutral in opinion, explained thoroughly and helpful! Thank you!
That's awesome.. Thank you. I have two more electrical videos coming out this week, One today and one tomorrow.
Love the hat - 24 year Air Force veteran here. Thanks for all the info. - I'm trying to get things straightened out at our house. Your videos are a huge help.
That's awesome.. Thank you. I love hearing that my videos are helpful and thanks for your service. 🇺🇸🇺🇸🇺🇸
As an electrician I always mount them ground down for 90 degree cords. It also works better for most wall warts for computers etc.
Have a window AC where design and weight really means ground down.
I’ve done both, but your latter points are what’s most helpful. 👍
My first thought at the start of video, was 90° plug issues with ground up version.
However...I used to work for communications companies, and among many other job duties, I performed quite a bit of work in several different hospital ERs. There are 90° male three prong plugs that are actually designed backwards from most three prong 90° plugs. The ground prong is on the opposite end from where the electrical cord enters the connector, so on a ground down outlet it would be plugged in "upside down", with cord on top.
I actually have a couple of this style male connector in use for some of my own extension cords with multiple female outlets on the other end.
I've been a musician for well over 40 years, and some of the smaller venues unfortunately do not have much available for electrical outlets. And often one of the other guys is plugged into an outlet that I need to use and they are already using a 90° in the bottom port on the outlet, so this way I can plug into the top with my 90° and it will actually work. I have extremely heavy duty cords that I use for these extension cords, I make all of that type of stuff up for myself. You might think, well why not just use a straight plug end to avoid that, the reason is because often in a stage setting you don't want cords sticking out away from the wall like that because bad things can happen, lol.
I did ground up in my shop where there is an increased risk of metallic objects falling on the plugs. And most of my shop tools are three prong. Elsewhere, I use ground down because that's what most people expect and, like you said, many low profile plugs are built with this orientation in mind.
Just wondering has anybody ever seen a ground down receptacle in a hospital every hospital I've been in or witnessed always face them up I believe they might be required to have them that way
Agree. It's really interesting when a metal clothes hanger falls on a dryer plug with a gap .
SO convinced that I will remember this as I plug in the flat bladed polarized plug on my battery powered: chain saw, drill motors, and rechargable dill pickle er.
I’m no electrician and I learned a lot from your video which is the point! Thank you for sharing your knowledge. I agree, with the ground up, it does look upside down! 🙃
Thank you! I’ll try to keep them coming.
Thanks! Our house has a combination of ground up and ground down, I always thought that it was bizarre. Now I know that the builder may have had a reason for installing the receptacles this way.
I built my house and wired it 45 years ago, i'm ground up. It just made sense to me to have the ground prong up to protect against a short.
I learned it the same way as you and I agree with ground down. I was taught that if the plug was to fall out of the receptacle the ground would disconnect last. I also was told that either way was ok as long as it was consistent throughout the job.
The ground pin is designed longer to make that not true. Its a pretty pervasive myth in the trade though. It's what I was taught in my apprenticeship.
lol, never thought of it this way, but that is why orientation of plugs is up for debate. you could justify both ways
I am not an electrician but agree that ground down is the best in most cases. When you push the plug in, your hand naturally wraps around the end of the plug to grip it. This causes your #1 finger to curve around the bottom of the plug. If the ground is facing down, your finger would only touch the ground. If the ground is facing up, you may touch the live blade of the plug. Great video!
Thank you..
I've actually seen angle plugs oriented either way. I have a coffee maker with a plug that points down with the ground up orientation, and installed a receptacle specifically that way for it. Someone subsequently installed an outlet for me ground up somewhere else and he explained to me the issue of a conductive object falling onto it, and it made sense. It's not just the short circuit issue, that any breaker will take care of. If the object lands on the hot prong it can become live, and a shock hazard. Previously I preferred the ground down orientation, but now I tend to favor ground up, and further, for a sideways mounted receptacle, neutral prong up. Glad to hear the national electrical code doesn't object to either way.
Of course, a partially plugged in plug is a potential hazard either way. If the outlet is worn so that the plug tends to fall out it's really important to replace it.
Thank you! Excellent Presentation. I do work all over the country and it is surprising how may electricians have been taught that up or down ground orientation is a code issue. Thank you for covering not only code, but also manufacturer instructions, AND national standards & Applications. Strictly for looks I like ground down. If there is a reason to not use ground down, it is that it looks more like a face which could attract some children to play with it. Some children will play with receptacles anyway, so I make mine safe with the rotating covers, but this is a thought.
Thank you! The tamper proof receptacle which have been required since 2008 solve the problem of kids trying to stick something into the receptacle. But when something is plugged in that will not provide protection. Thanks for your comment..
I'm not an electrician but I learned alot from this video. All great points, probably why there is no code requiring ground up or down.
That is the whole purpose of the channel.. Thanks for your comment.
In Biomedical locations about 30 years ago we switched from Ground Down to Ground up. I remember when hospitals and clinics went through the entire facility and reversed
ALL receptacles to ground up. This was in response to a nurse being electrocuted when her neckless (or ID badge chain) came into contact with a partly inserted plug.
This is the preferred method in many manufacturing facilities for that very reason.
Ground up always made the most sense to me as it provides a little protection from something falling and causing a short across the two prongs.
Seems like there's always sheet metal in shops! Finds its way onto the prongs. But I still like "Green is ground and ground goes down."
How is that possible, you would have to put your face through the wall to get your *NECKLACE* or chain close to the wall. Arent outlets at medical facilities at 45" from the ground, so no need to bend over?
....Thanx, didn't see this before I commented, wow, had no idea it stemmed from one incident!....
Good points in this video. Ground up is the safest way. All my unused receptacles are installed this way. The ones that are behind appliances are installed according to the appliance's plug configuration. Most appliances plugs are designed for ground down configuration, so I have no choice.
I was explaining the "correct " orientation to my client and measuring the wall for layout code requirements. I pulled out the tape and went across a receptacle which had something plugged into it. When I accidentally let go and it arced perfectly down across the blades. Burned the tape, receptacle and wall. Perfect example neither of us will forget.
I've also heard that when mounting receptacles on their side that you should mount them neutral up for the same reason that you would ground up in a vertical installation. But I agree, vertical outlets look odd ground up.
When I worked at a hospital, we were required to have ground-down at 18 inches or less from the floor and ground-up above that height. The reason for ground-up above 18" was that the ground lug added stability to the plug, helping it stay in the receptacle. Makes sense to me.
All the hospitals I have (and am currently) worked in have been ground up, and one of the electricians showed me why. Very simply, with the ground pin up, if the plug is partially out and something metallic (such as an utensil) falls between the plug and the wall and makes contact with the prongs, the first prong it comes in contact with is the ground pin. That way when the object makes contact with one of the other prongs it is more likely to short to ground, and not short across the hot and neutral contacts instead.
@TomMcdonald9AYahooDotCom Some of the NEMA receptacles lock into place. Plus some have the neutral and hot at right angles to each other making it more resistant to pull-out.
If appliance manufacturers started making their plugs to support Ground Up it would be the obvious choice, aside from personal preference in appearance. 🙃
Hi John. I am In Houston TX, and I have never seen an actual stated preference in the NEC. But your explanation of when a receptacle is controlled by a switch is a good method to assist in identification of a single or two receptacles. Either way is compliant. and an inspector may ask. We have a few tough ones, but their concern is primarily life safety. The ground up method for safety is interesting, but most applications are designed for ground down. I think as long as the receptacle is secure, its likely ok. It is good to review the basic principles occasionally, and your previous video of the NEC 2023 changes to Neutral or Grounded conductors was a good reminder, especially if it is a new installation. These are great videos.
Thank you so much my friend. We have family close to Huston in Baytown TX. I spend most of my career working as an electrician and then an electrical engineer for Texas Instruments. I have been to Dallas quite a few times over the years.
In North Carolina the code was changed in about 1996 to specify that the ground should be up when using a metal cover plate. The local inspectors would overlook ground down with plastic or wooden plates. I have done both in my years as an electrician except for state owned facilities which required ground up.
WHY? would a conductive covered metal plate have any safety issues? Maybe with it's desired use on metal boxes? Ref: 110VAC US Navy film on "Your deadly shipmate"! ( 1963?)
If the plug is slightly loose and the plate comes loose it will fall across the hot and neutral pins causing a short. That was the rationale behind the rule in North Carolina.@@georgedunkelberg5004
In addition to the 90° plugs, although not as common as they used to be, every three prong "wall wart" power supply I have ever seen is designed for ground down.
I’m an electrical/electronic DIY person and I just go by what seems normal. I wire residential houses “ground down”, and commercial buildings “ground up”. But I like the idea of manufacturers making 120V outlets so the ground prongs point towards each other. Then there’s room to plug in two of the larger transformer chords.
That’s my 2 cents. Thanks for looking. 😊
It bothers me that you are doing any work other than on your own home if you are a DIYer in electrical. In my state, which has fairly relaxed enforcement compared to a lot of other places, what you are doing is illegal - when you "wire" residential houses and commercial buildings. Unless you are a LICENSED DIY electrician (🤣), you should not be working on anything that is not your own (local and state laws typically allow the unlicensed homeowner to work on his own home, not any others)
I have seen “face up receptacles” for decades in stores, offices and so on. But the “spill into” comment is correct. When I worked for the local City, we converted all floor receptacles to overhead receptacles.
My house was built in the 40's and I would be grateful for ground 'at all'. I'm replacing cloth braid 2 wire with 12/2 NM-B. Lots of work ahead.
Ideally ground up is actually the best for safety. Hospitals, other institutional and industrial jobs liked to specify ground UP. Some trendy goofy architects like to have the outlets all mounted sideways, and in that case ALWAYS put the longer slot neutral side UP. Otherwise you have the hot tab up. Generally over 90% of the time the ground goes down. New consumer grade 90 degree plugs are made for ground down but older cords on consumer, commercial & some new and all old industrial equipment 90 degree plugs were made for ground up.
Been doing ground up for years after a friend pointed out the exact scenario you did with the screwdriver. I work for a home goods manufacturer and some of our units are coming with low profile cords with the ground up.
I also have some (but not all) GFI outlets that the "test" and "reset" lettering is oriented for ground up install.
Thank for sharing.. 👍
@@Bryan-Hensley
Really?
#1 if that's the case and this is sooooo dangerous, then why isn't it code to specifically put the ground wire on the bottom?
#2, a majority of cords that most people use inside of the home day in, day out only have two prongs and no ground (specially one's the kids may be plugging in). If this is soooo dangerous to occupants and children, why are you and I not reading about kids being electrically shocked every single day? According to you, if that ground prong isn't down the bottom, everyone's index fingers will be touching the hot prong.
As for what I was taught in school is no matter what, you NEVER touch ANY prong while plugging anything into an outlet (whether upside down or not 😉 )
@@Bryan-Hensley But is it code? Or is does code allow either way?
@@Bryan-Hensley Sounds like post-hoc reasoning to me. I certainly haven't noticed humans being shocked more often in hospital ICU's. Do you have any data or studies to support the notion that people instinctually hold plugs the way you describe.
LOL!! I am saving this for my bride. Only a couple of weeks ago, she got a good scare (thankfully, not hurt) when the chain she had hung on a plug (don't ask me why!!) fell down and created one heck of an arc.
Like you, besides ground-down looking right, I have encountered too many three-prong plugs that would put unnecessary strain if used in a ground-up outlet.
Plus with something like a necklace it would have shorted either way.
My 60-year-old house was originally ungrounded. At some point, grounding wire was added to several of the circuits, and the electrician changed all the receptacles, wiring the grounded receptacles ground down and the ungrounded receptacles ground up. I've added grounding wire to several other circuits, replaced all the receptacles with GFCI, but I've kept the same convention (although I've also added "Not Grounded" labels to the ungrounded receptacles.
I've seen both wiring methods used; it seems to be simply a matter of preference (although ground down seems to be most common). I've even seen receptacles mounted sideways, particularly in older homes.
Great point! There are some jurisdictions like Chicago for example which require horizontal receptacles. They also require conduit in homes which must really drive the cost up for the homeowner.
In those cases, side mounted receptacles have the neutral side up, theres no code that dictates that. Its just standard practice.
@@BackyardMaineYes, I work in the Chicago area. We do use horizontal neutral up mounting and conduit on everything. 6' flexible whips are allowed but discouraged. I've even had to replace whips 5" too long...inspectors can be rough. Those areas where I mount them vertical I use ground down.
I liked this video. It agrees with everything i have thought about in wiring in a new receptacle. 30 years ago NEMA was pushing more ground up.
I find that it’s easier installing in ground down also.
Another good reason ground down is most all the plugs 🔌 ( and lots of them made in foreign countries) for things like blow dryers are made to plugged in ground down . Maybe NEMA should ask Taiwan which way would be best next time they want to recommend changes.
when I started to install my 1st outlet I came to this problem which was quickly solved by thinking the 'ground' is down because that is where the 'ground' is and that is where the ground wire is connected outside. literally to the ground. and I also think it looks better that way.
Ground has gone down for my 35 years of construction
Late to the party. I normally install vertical receptacles ground down. Personally I think it looks better, also when using right angle plugs the cord is orientated toward the floor. I install horizontal 120V receptacles with neutral on top for a tiny bit of extra safety. But as you said it is up to the installer.
I really like the way you presented this topic, you are good!! And yes I agree ground down is standard. Infact the writing on the Leviton Decora receptacle's is readable when ground is down. That said do it as you prefer.
Thank you..
I haven't looked through all the comments, but some appliances have plugs angled from the cord into the plug body. I'm just a handyman, but an elderly electrician schooled me to install the outlet so the cord is in a relaxed position when it's plugged into the outlet.
Every house (that's six houses) we have owned has had the receptacles installed with the ground plug down. If you have any flat plug extension cords, the ground plug is usually on the bottom. If the receptacle has the ground plug on top, the cord will curve over the top instead of lying against the wall.
I worked as an electrician for a public water utility. We put the ground up for the reason with using extension cords. We found when dragging the cords around working from high ladders or across the floor the plug would have less chance of pulling out from vertical up or down pulling.
I noticed that, but with vacuum cleaners. For some reason the ground-up helps support the plug. Of course most of the "sag" problem is from installing the cheap 70 cent outlets. They can start failing in as little as 10 years. The better outlets are stiff; another reason for ground-up. (Most plugs have a "bump" for the ground, giving your thumb a place to press and keep your trigger finger away from the contacts.) That said, my contractor installed them ground-down when splitting an overloaded circuit... so I continued ground-down when upgrading outlets thru the house. The initial build had about 1/3 installed ground-up.
Ground down in my house and I have never had an issue. Ground up just looks wrong and it's my personal preference!
My house is old so I seen this video months ago so I started looking I had plugs upside down so I fixed them
All after watching this thank you sone of my plugs had to of been 45 years old years ago I was living with my grand father he had the old push buttons in the work shop in the basement they had like ivory in the push buttons I’ll never forget them
Light switches
In my apartment they were all ground up, but some no longer are. 🙂 I believe the code started out with ground pin down. The reason the rule was relaxed was that sometimes, on old installations, wire length was insufficient to replace the receptacle - unless it was put in with ground pin up. I still would reverse a receptacle to ground down position, where something like a wall wart or a right-angle plug doesn't otherwise fit.
I always thought ground up was for hospital installations to reduce the chance of spark in an oxygen environments. But, I like the ideal for switch outlets going ground up also.
That's what ground fault receptacles prevent I thought
As a Home Inspector I see it both ways and really appreciate the research of all viable codes/sources for an answer. This video was very professional done and informative which gives me the knowledge to pass to my home buyer.
Thank you. So glad it was helpful..
Whatever's in the home all receptacle should match whether ground up or ground down all new construction should have ground up as the code requires to comply with manufacturer's recommendation on every box for receptacles there's a picture and it shows ground up. On an ungrounded system where receptacles there's only two prongs instead of three the large prong should be when looking at the receptacle to the left. As a home inspector you do know that the code clearly states that receptaclesare to be installed under the code for the permit of the construction of that area so if a house was built when knob-and-tube was installed it has two wire receptacles it does not require to be grounded unless a remodel had been done and then the remodel must comply with the code at the time of the remodel for only the area that was remodeled. Same complies with GFCI and arc fault and now that the new codes come out we're proper tamper receptacles are required solely based on when the last permit was pulled for the area that's being inspected. Meaning if a room was remodeled it has to comply with the newest code but if it was not remodeled say last year and it was built in 1960 then it must comply with the code of 1960 not with today's code.
@@ds9902 I don’t know what state you “claim” to be a home inspector in but you are definitely full of it, you don’t even know what you are talking about.
@@ds9902 Like I keep saying the Manufacturers and even NEMA do not recommend orientation. If they did we wouldn't be having this discussion .
I have put a non-grounded GFCI on old two wire and the series afterward upside-down.
Make sure to label "No Equipment Ground" and "GFCI Protected" on those few outlets. (edit: the GFCI creates a "reference ground" for the GFCI)
My old school training was that there was a purpose for the flip, like (in the video) a switched outlet.
Absolutely the best informational video for a DIY’r like myself. Greetings from OKC…..and Thank you for this post
Glad it was helpful! Thanks so much for watching and for your kind words.
I prefer ground down because many(most) plugs and especially wall warts don't work right in the ground up plugs! Don't forget that even if it doesn't have a ground it most likely does have polarized plugs and so they get forced to be upside down. I have even had one wall wart that would fall out when forced upside down.
My buddy tried using a Klein outlet tester on a ground up oriented receptacle and realized he couldn't see what the tester was showing because the display was facing the floor.
I’m not a liscend electrician, bu I have done wiring for many years. Residential, commercial, even industrial. But please tell me what a wall wart is😆
@@karlschauff7989Exactly!
The little 3 light testers to check for correct wiring, you can’t see the indicator lights! I’m a ground down man all the way.
@@ronniealexander8967 AC to DC power converter. If the cord has a big box that plugs into the outlet that is a wall wart.
Ground-LEFT is the most underrated socket installation. It offers superior protection for both 3-pin AND 2-pin plugs, as it puts the neutral pin directly above the live, making it nearly impossible for any dropped item to cause a short. A byproduct of this orientation is that the screw terminals for the live conductor will be facing down, which means a loose wire or other debris inside the socket enclosure will have a lower chance of falling into contact with it. Another great perk of this configuration is that it will allow 90°/45° plugs to come out at an angle that still faces downwards. It allows plugs to fit nicely and out of the way under countertops or cupboards, and also doesn't put as much strain on bulky plugs (like those with built-in adapters or circuit protection) as ground-up installations do. As an electrical controls engineer, I always try to use the ground-left orientation whenever I design a panel with built-in sockets.
I always install ground down. People have a tendency to unplug a cord by pulling up as well as straight out which will many times break off the ground .
39 years in the trade before retiring. I always preferred and installed them DOWN !! Whenever asked, my reply always was "it's a "U" ground receptacle not a "horseshoe" ground receptacle. Which way looks like a "U" ?? At a code class years ago they mentioned the same reason you did for mounting the ground up. So, only in those instances. Never heard the "switched outlet" logic. Learn something new every day ---------------- no matter how old you get !!! ;o)
Thanks !!
My pleasure.. Thanks for watching.
As a master electrician and a teacher in the electrical industry, I'll admit I came here expecting to get into a fight 😂 but your explination was spot on and very watertight.
I too was always raised to do ground down, with the "first make/last break" arguement. If someone were to step on the cord, the ground is still fully in tact, while ground up could potentially be an interrupted grounding connection while the ungrounded connection could still be established.
Basically, at this point I just tell guys "pick a method, and stick to it." If it's grounds up for you, make sure they all go in that way. Uniformity is neat & workmanlike. 110.12
I get that.. I watch some other channels doing electrical and they don't know what they don't know. I usually don't comment though because they do also have some helpful content that people like. I worked for almost three decades as an industrial electrician and then spent my last ten years working as an electrical engineer for Texas Instruments. Im retired now. I did some teaching there as well.. Mostly electrical safety (NFPA70E) and LOTO. Some procedural stuff as well.
@BackyardMaine I teach code, 70E and 79 classes, mostly in the midwest for continuing ed credits for electrical licenses. I also do a lot of arc flash training for industries.
Ahh looks like we have a lot in common. I was the facilities electrical engineer for a Semiconductor FAB here in Maine. One of my projects was to complete an arc flash coordination study for the site. It was a big project which took over a year to complete working on it a few hours per day. We brought four 35kv feeders into the building which fed 26 dule fed (main/tie/main) substations. Plus over 600 electrical panels, 30 UPS system including three rotaries and four 1 meg generators. The FAB ran production 24x7x365 so tuning off the power for expansion work was almost impossible. I built a permit process for energized electrical work which required senior management and safety depart head signatures. They did't like it but it covered my butt. Part of the permit would list the incident energy level, required PPE, procedures etc. Im retired now.. @@eklypse69
In my opinion, based on a lifetime of experience, the greater concern is the quality of the duplex outlet. I submit the "residential grade" outlets should NEVER be used - anywhere. The lower quality materials mean they all too quickly wear out; thus resulting in loose connections with increased resistance, heat buildup, and fire danger. Additionally, the housings seem to crack far easier than any spec or commercial grade unit.
In Australia (where I live) the standard configuration is ground down. However, all modern plugs have partly insulated pins, so if it's only partially inserted, no live metal is accessible. In the UK, ground up is standard, but I believe their plugs now have partially insulated pins too.
I usually ask the customer if he (or she) has a preference. However, I prefer the ground pin up because if a metal cover plate is being removed and falls onto a plug, the power and neutral can contact the metal cover plate and short out causing a loud pop and lots of sparks. Not a desireable outcome. I often inform the customer of this possibility and many decide they want the ground pin up.
You shouldn't be removing a metal cover on a live outlet anyway. And who leaves cords plugged in when they are removing a cover plastic or metal?
@@fauxque5057 I wouldn't do that, but can you guarantee that the customer's kids won't do something that stupid? Unless you can guarantee the intelligence and common sense of every person that will ever be in the customers environment, and also keep a screwdriver out of their hands, it's better not to assume, It makes an ass out of you and some Mechanical Engineer. Stick to commenting on things you actually know something about.
John, there is another mitigating factor I personally ran into. The local fire department. I used to be the maintenance Forman in a Culver City, California manufacturing company, the local fire inspector had me turn every blasted receptacle upside down, close to 3000 or so. His reasoning was not only the falling object short, but he said all the hospitals have to do it that way. This was about 40 years ago, so this whole issue was probably new and open discussion for everyone, I would guess. Ground down looks right side up to me. But also, if you have an object fastened against the wall firmer at the top than bottom, it would seem to me the holding power would be greater than vice versa. It seems to me the two blades would have more of a holding power than the single ground. In other words, it seems to me with a good plug (not an old lose one that needs to be replaced) would have a harder time to roll out of the receptacle. Well, that's this reporters' opinion. LOL I'm with you no matter how I slice it.
Great information.. Thanks for sharing my friend.
@@BackyardMaine and they got paid lots of overtime to change ALL 3000 outlets!!!!!!
I worked in a hospital in Southern California for 11 years, and it had all the receptacles with ground up.
@@David-rx5eo Well, there you go! If California is still doing it today, it must be wrong. LOL
I know some if not all have the embossed text on the back in both directions these days. But back then if you installed some receps ground down, the text on the body of the recep would be upside down.
When we bought our current house, all the outlets were installed ground up. It drove me crazy so I changed them all to ground down. Pretty much all 3 prong flush mount plugs are designed for ground down.
I agree..
When I built my house 27 yrs ago I hired my best friends brother to do my electrical work. He was an industrial electrician who decided he was going to do residential wiring. This turned out not to be such a good idea on my part. While he was a good electrican, he didn't know anything about residential construction and made some very basic mistakes that caused issues (recepticles over the counter too low prohibiting the use of the counter backsplash, running wires across the basement stairway before it was cut out, etc). We caught and corrected most but one that I didn't was he installed every recepticle ground up. Most of the time this isn't a big issue but when you put in a 3 prong plug in as you mentioned, the plugs want to be installed ground down. I could (and probably should) flip them all around but since it hasn't been a big problem I just haven't done it but in my opinion, ground down is the way to go. Any that I've installed since have always been ground down.
I always do Ground Up for the arc safety. But it really comes down to who folks trained under - that seems to be the primary determinater of which method folks follow.
Maybe in a commercial metal working shop? But probably not, at least for me. No where else would seem to benefit. Particularly residential homes.