The Dangers of Shared Neutrals: How To Avoid Being Shocked

Подписаться 750 тыс.

Просмотров 242 тыс.

50% 1

In today’s age of electrical work, shared neutrals are relatively rare. Most of us run an independent neutral with our phase conductors. But can you receive an electrical shock from a shared neutral even if the breaker is in the off position? In the latest episode of Electrician U, Dustin explores this topic to bring some light to the subject.
🤘⚡️EU Learning System⚡️🤘
For Individuals --- electricianu.c...
For Businesses --- electricianu.c...
-Video courses on every side of the electrical trade (theory, code, safety, wiring, install, troubleshooting, leadership, and more)
-Practice exams for 2017, 2020, 2023 code
-RU-vid videos categorized and searchable
-Audio lessons
-Forum
-Business version has admin portal and ability to assign learning to technicians and monitor progress
-Any business size from 2 techs to 2,000!
🎓💡CONTINUING EDUCATION💡🎓
Sign up here --- electricianu.c...
-State Approved
-Video Based
✍📝PRACTICE EXAMS📝✍
Get them here --- www.electricia...
-2017, 2020, and 2023 NEC versions
-Online Residential Wireman Exam
-Online Journeyman Exam
-Online Master Exam
-300 Question Online Code Cannon (not license specific, all code)
-Take as many times as you want
-All of the above come with printable PDFs
🎤🎧PODCAST🎧🎤
Spotify:
open.spotify.c...
Apple Podcast:
podcasts.apple...
📱👍SOCIALS👍📱
TikTok - / electricianu
Instagram - / electrician_u
Facebook - / theelectricianu
Reddit - / electricianu
Rumble - rumble.com/c/E...
Discord - / discord
🎧🎹Music, Editing, and Videography by Drake Descant and Rob LeBlanc🎹🎧
#electrician #electrical #electricity
As discussed in previous videos, electricity travels in loops to function. On a single pole circuit (120v for example) the flow typically leaves out on the hot wire, goes thru the load, and returns to source on the neutral conductor. In addition, in most current residential work, a single dedicated cable, comprised of one hot, one neutral, and one grounding conductor, is run for each separate circuit. So, when you shut the breaker off, there isn’t a chance to receive a shock on that circuit since the loop is broken.
However, in past years, shared neutrals were fairly common. A shared neutral is where you have multiple hot conductors sharing the same neutral. This was done to save wires and therefore save money. However, there are dangers present when using shared neutrals. That being, even if you turn off the breaker for the circuit you are physically going to perform work on, that neutral conductor can still have current flowing on it from the other circuit. To combat this issue the NEC now requires us to install a multipole breaker (or place handle ties on the single pole breakers of a multipole shared neutral circuit) so you are made to shut off ALL the breakers involved with a shared neutral circuit. But this provision is a fairly recent change and you can still find single pole breakers for a shared neutral circuit all throughout the country.
There are a few scenarios where you could receive a shock on the neutral conductor of a shared neutral circuit. If you left the breaker on but took apart the joint on the neutral drop in the box and touched the white wire headed to the panel and either of the other 2 white wires headed to the actual device, you will just be completing the loop itself! Another way to get an even worse shock would be to leave the breaker on, take apart the neutral joint, and then touch the 2 white wires headed to the devices themselves. By doing this, you are basically completing a 240v loop and will get a wicked shock!
The easiest way to avoid all of this would be to simply turn the circuit off that you are working on. And if you are working on an older shared neutral circuit with single pole breakers, then shut them both off! This eliminates the chance of having any voltage on the neutral. Another thing to consider regarding receptacles. The loop is NOT complete, so current CANNOT flow, until something is plugged in somewhere in that circuit. The loop is open at the device itself. Lighting on the other hand, is connected via the lightbulb itself (or the filament within the light bulb) so current will flow as soon as you turn the breaker and the switch on! Another thing to consider, is that current does NOT care about the color of the wire! So just because you are touching a white wire, doesn’t mean you won’t get shocked if you are doing something you shouldn’t be doing with it!! Always get your journeyman’s tips or advice before attempting to work on a circuit until you fully understand the exact scenario you are up against.

Опубликовано:

29 сен 2024

Ссылка:

Скачать:

Готовим ссылку...

Добавить в:

Мой плейлист

Посмотреть позже

Комментарии : 624

@Ephesians-ts8ze Год назад

I went to work for the state (TX) recently and it’s pretty common for the electrical contractors to share neutrals on new installations. I’m a maintenance electrician and I’m getting pretty frustrated with the crap they leave behind for us to deal with. There’s shared neutrals everywhere and an “anything goes” color code. In Austin it’s red, black, blue for low voltage and brown, yellow, purple for high voltage. But within Austin’s jurisdiction State jobs are not subject to AHJ. So some contractors do it by Austin code and others do it by everywhere else color code.

@workingshlub8861 Год назад

up here in new england i see this all the time with older homes....nothing is ever labeled in the panel of course..

@dracula3811 Год назад

The shared neutrals on new installations being allowed is on the inspector for passing it. It isn't code.

@Bobcat1950 Год назад

Several years ago I built a post and beam garage. I intended on doing a little woodworking and other projects. I was very busy and couldn’t find the time to wire it myself. I hired a seasoned electrician with a great reputation. I had already set the sub panel and pulled the cables. I explained that I wanted 3/4” conduit with metal boxes and GFCI receptacle on each circuit. I came home and found that he used 1/2” conduit and shared the commons and grounds and had not installed the GFCIs. I called him and he said, “The GFCIs were not necessary and that he was able to pull all the wires through the 1/2” conduit. I paid him and a few weeks later installed the GFCIs which wouldn’t work. After asking an electrical engineer, I found out that a GFCI meters between the neutral and the hot wires not the hot and ground. They shouldn’t be wired using a shared neutral.

@Goldern 11 месяцев назад

GFCI calculates the energy going in (hot) and going out (neutral), if the difference between hot and neutral is big (someone turned into Earth and got zapped) then it will automatically trip itself preventing further damage. It does not care at all if Neutral is shared or not, but bear in mind that after Neutral and Hot exits the GFCI, you can’t connect equipments before the GFCI Neutral and after GFCI Hot or there will be imbalance and it will trip. The simple fix is to put a neutral bar connector after/before the GFCI, that way if you need to put an outside circuit that won’t be affected by the GFCI (like a light circuit, to easily find the GFCI after it trips and then reset it), then you’ll be able to wire the light breaker before the GFCI and finish it with the Neutral before the GFCI.

@christobaldaetz6062 Год назад

Back when I first started as an electrician, we ran a 12/3 for two circuits. But in the panel, we installed a two pole breaker. So that when you had to work on that circuit, you could do it safely. Now they make 12/2/2 makes it easier to deal with.

@davidwoodard1820 Год назад

Great video! Your statement that will stick with me from this day forward is "Electricity doesn't care about the color of wires".

@bernsfindsandmore7636 Год назад

Works for me as well... if only life was this way as well...

@jerrybennett9198 Год назад

One other thing happened when I was having my business rewired in an old 1937 commercial building with one, two or three businesses being housed in it over the life of the building. The electrical panels and wiring had been changed and upgraded (sometimes by amateurs) several times. The landlord had a supposed electrician come in and change the timer for the signs from one business in the building to another but the conduit to the sign was still in the first business location. The pseudo electrician took his power from the other business main panel but somehow left the connection of the neutral on the first business main panel, so there was a hot wire from one panel and the white wire from another main panel. So my commercial electrician who was installing whole new panel for my business shut all power off to my panel at meter. As he was pulling the main leads the hair went up on his arm near the neutral and he stopped immediately. The back feed was quite significant. Traced it to that old timer box. I think it was a once in his 15 year experience happening. Still when all power to the business is shut off and supposedly we all had our own meters, and main panels, i can see the mistake would be easier. But you have said always check for current even in a dead box. Jerry. PS Love your channel. Have watched most of your videos

@garretrobinson3668 Год назад

It’s pretty wild to hear Dustin mention my name. I’ve been watching the channel since I first got into the electrical trade and it’s been a huge help. I appreciate you sharing your knowledge and experience with the rest of us. Thanks!

@chadg6874 Год назад

The only thing though is your comment needs to say "bruh" and is missing a 🤙

@louisogden803 24 дня назад

When I was an apprentice, in another century, I was shocked by a neutral on a 3 phase situation. I had turned off the circuit I was working on but the neutral was carrying the load of 2 other lighting circuits. Fortunately, I was on a three foot rolling scaffold and fell to the ground pulling myself free from the neutral. Beware of neutrals on a 3-phase system.

@Cnightz Год назад

I just fixed a wiring issue in my house that had this problem, but a more severe violation. 14/3 wire running 6 rooms upstairs. Every neutral receptacle was discolored or burned. I fixed it myself Raj 2 home runs to separate junction boxes.

@johnt2491 9 месяцев назад

I'm not an electrician by trade. Yet watching this video made my jaw drop. 😮😮😮 WOW (and scary). Fantastic information, thank you so much!!!!

@omrtnz5100 Год назад

Thats good to know. Just bought a house with older wiring and I tend to work basic repairs or replacements live. But never again until I make sure its 💯 safe.

@alphaforce6998 3 месяца назад

For those people wondering why even do this, the answer is simple: a shared neutral lets you run a single three-wire conductor for two dedicated 120V circuits. So you are essentially halving your wiring material costs. It is called a branch circuit, and it works by connecting the "hot" wires to each of the two 120V legs at the breaker, as you would for a 240V circuit, but when you wire the outlets, instead of having two hot wires go into the outlet you share the neutral between them. But wont that overload the breaker if you did this with 20A breakers? If you draw 20 amps from both circuits, won't that be like 40 amps on the shared neutral? No, because the two legs are out-of-phase, and as such, the current flowing on the shared neutral will max out at 20 amps, as the phases are inverse and cancel each other out. In other words, the neutral wire never sees more than 20 amps even if both of the circuits are power some high-current appliance like an oven or portable AC.

@anthonymwangi1661 Год назад

You are awesome man. Keep up doing what you do. Always feel appreciated. From Kenya.

@jesstreloar7706 Год назад

Replacing a stove receptacle. Opened the dbl pole breaker. Took the old one out and touched the neutral and ground at the same time, WTH! Outlet right next to the stove nothing in the box to indicate where the neutral was shared at, but, yea. Flipped the breaker labeled kitchen recpt. I was good. Good lesson though, now I check all the wires to ground, all the wires to each other and ground to all wires. I know I tested the ground 2x, but I really don't trust anymore.

@johnm840 4 месяца назад

Nice video, As an EE, with 30 years experience, I see nothing wrong. with your explanation. Recall as a rookie engineer, we were dong an upgrade to an OEM machine. they had 2 different breaker in a panel, not even close to each other feeding a 240VAC load. I was like really, we had to call in Electrician to re-wire the box to fix this. They were pissed of at new rookie, but I had to raise a stink to have it done right.

@creating-infinity 4 месяца назад

I like this video, with that said I’m not understanding why he is saying that you won’t get shocked on the neutral of the dead hot. If your not grounded then yes you will not get shocked because you just become part of the potential of there is an imbalance. Key word being the imbalance there. But if you become grounded you will get hit off that neutral because you become a second pathway back to earth for the live hot.

@heyitismyusername Год назад

I figured out I had a shared neutral when I installed a GFCI and it kept tripping when I flipped a 3-way switch on a 'separate' breaker.

@jackl9922 Год назад

My house is full of shared neutral. I always check neutral to ground. I also made certain, none are on the same leg in my panel. When I changed the panel, inspector told me I should have used double-pole breakers, but he still passed me since ‘better than before’. I swapped Federal Pacific panel to Square D. I have not spent the money to change breakers again since aware of the issue. Probably every house in my neighborhood is the same, and most still have that awful, ‘fake’ breaker panel.

@sigcrazy7 Год назад

You don’t need to replace your Sq D single-pole breakers. Just buy some handle ties and installed them on those breakers feeding the MWBC circuits.

@IDGAF-FU2 6 месяцев назад

I don't know if you read comments on these old videos. I'm just learning about electricity to do some home maintenance. I also have an 11.1Kwh solar array in my field and I want to learn how that works. I think you just saved me from some curly hair or refried beans. I was going to flip one breaker to remove a ceiling light. I still need to learn how to use the testers. I will continue to watch your videos. Electricity seems to be a lot like English: "I before E except after C" (except "weird", "leisure", "neither", etc.) I do have a question. Where does electricity get "spent"? If it continues to flow, after it powers a device, does it flow down to the next house? I understand the difference between AC and DC, where DC has a limit in travel distance. A log gets spent when fire converts it to heat. Are there fewer positive ions in the wire in the loop after lighting the bulb? I think about shit like, where does wind go when it's finished blowing?

@smeado3533 Год назад

My house has three multi-wire branch circuits. I almost fried my furnace when I kicked a neutral loose in my attic for my washer and created a high voltage on my furnace and low on my washer. I'm not a fan of them.

@bc1173 Год назад

3 phase is much more dangerous for shared neutrals and much more complicated/important to know.

@keything8487 Год назад

that will F your day up !!!....especially onna 277 lighting circuit with shared neutral !!!

@genebowdish.mageniemagic 10 месяцев назад

Stories of people getting shocked on an electric water dock, or in a lake, or swimming pool, or raining on Christmas lights, or raining on power tools

@Gordon013 4 месяца назад

Found this out the hard way in my house. Turned off the breaker and still got shocked by the white and was like these whites are on different circuits. My house has some odd electrical. couldn't figure out what two switched in my bedroom did for a year. Turns out they are 3way switches that also turn on the outside lights which you cannot see from the bedroom. Also had a live line going to the outside of the house that was just cut right at the foundation and left. discovered that while trying to figure out why the breaker kept tripping while power washing . Also most of my receptacles are split. one on a switch and one always on.

@johnnyarsenault9124 Год назад

I’ ve seen a Star connectioned transformer 347/600 volts which wasn’t connected in the middle with a common ground. If somebody would be grounded and touched any (now insulated) ground would get zapped with a 347 volts shock, easily remedied by grounding the middle of the star transformer.

@jmdavison62 10 месяцев назад

Related: how even resistive loads don’t cancel out if you’re served with two hots from 120/208 VAC service,

@alphasaiyan5760 Год назад

That’s why , if you run across a situation like that , if there isn’t already , you install breaker handle ties so that when you turn off one breaker the other breaker has to turn off too. That stops the possibility of potential on the neutral. If the breakers aren’t next to each other in the panel then you move them around so that the shared neutral circuits can have breaker handle ties installed.

@barryomahony4983 Год назад

And it's an NEC requirement 210.4(B)

@alphasaiyan5760 Год назад

@@barryomahony4983 yes sir

@simi_Fili_Tongi Год назад

Thank you just what l needed!

@topwaterfrogger8428 8 месяцев назад

Great Videos! I have a Question!!! How would the scenario below effect the True Neutral going back to the Panel box??? I'm a carpenter, not an electrician but I have working knowledge of electricity. On a bathroom remodel I was taking down two can lights from the ceiling that operated on one switch that were going to be relocated in the same room. 12-2 (power from the breaker box) was coming into the light box in the ceiling. He ran one 12-2 wire to the switch in the wall to send power to and from the switch back to the light. So, in the light box I had a white wire that was actually a black wire(power), and it was tied into the black wire that ran over to the other light for its power source. Usually when I see this the electrician has always put black tape on the white wire coming into the box from the switch so you would know it was being used as a black(hot), but he did not in this case. So, looking in the light box in the ceiling you would see two blacks together, two whites together and a black and white together.

@marktheunitedstatescitezen185 Год назад

What about a 230v line ? The L-1 is + 115v & the Neutral + 115v and Ground is Ground !

@bryanduchane2371 Год назад

Can you do a video how the TENS Units work with high voltage and low ampacity by using capacitors. In case you don't recognize what a TENS Unit is, it the electrical medical messaging device that uses electricity going through patches you put on and it causes your muscles twitch or tighten for a determined time frame and intensity. Just started using one on my shoulder that had been a constant source of chronic pain for me since 2010 due to 3 cervical neck fusion surgeries.

@Noc4Beez Год назад

If a metal box is grounded and you touch the neutral and the metal box at the same time you can get 120 because you are complete circuit. The ground and neutral goes back to each other at most panels and the neutral is going to want to pull off the ground to make the loop

@jjperera3389 7 месяцев назад

Yep I got socked yesterday by a shared neutral

@floydross735 Год назад

Just don't touch 2 points at a time. Practice on all off circuits like they're hot and be aware of where your hands/fingers/elbow/head/legs are touching. If you don't have thick enough clothing or gloves, the current will flow through it. Disclaimer: always turn off circuits and LOTO, don't work on live wires.

@floydross735 Год назад

When disconnecting wire nuts and separating 2 wires, if there is a spark, there is a load running through it ⚡️⚡️⚡️

@martf1061 Год назад

👍 exactly

@josephdestaubin7426 Год назад

I love your content and really appreciate the work that you do. Having said that, I'm always a little confused about why it would matter whether the powers turned off or not. If PPE has been uand proper procedures be used, it doesn't generally matter. I will readily admit that there are times when I will absolutely turn power off, for instance when there's a mechanical device like a condenser fan replacemeant, or I'm pulling a motor, We're working on sense of electronics that I need to unplug and I need to protect. But the usefulness of having the power live, particularly when doing diagnostics, really can't be overstated. And yeah, you get shocked when you first learning how to do this,. But if you can survive the apprenticeship, you learn not to get shocked. Having said that I've been bitten by 120, 208, and 277. Those last 2 are not fun, but also not something that happens more than once.

@bryanreese907 Год назад

Disconnecting neutral first will burn up LED drivers quick. True story.

@williamwhelchel508 Год назад

How about something on phase converters ..... single phase 60a to 30a 3-phase? I suppose it requires a run motor to produce the 3rd phase?

@soulergy1soulrgy1 2 месяца назад

Keeps me from getting zap! Thanks...

@brianpalma6101 Год назад

My question is why do wire manufacture’s still make 12/3 nm and mc even though it’s code not to use shared neutrals

@TlD-dg6ug 9 месяцев назад

Shouldnt a shared neutral be a lower gauge wire? Like lets say you have two circuits with the smallest imaginable load, but both active so both returning current. Wouldn't that potentially overload the white? Im sure there is some safety margin in there, just curious.

@genebowdish.mageniemagic 10 месяцев назад

Power company loses neutral to city block and the Shopping Mall

@italiarican2006 Год назад

sharing a neutral on light bulbs.... i need to install bulbs bulb i dont have any way of getting another neutral all the way back to the neutral bus on main panel. is it safe to just use a wire connector on a nearby receptacle to attach the bulb neutral so it has a completed circuit?

@johnthompson5409 Год назад

At the Breaker box there is 2 120v which stagger on the breakers if you have 2 plugs or what ever coming from the same side of 120 you will only have a total of 120 until you connect to the other side of the 120.Then you will get 240v ??

@peterzwyth4347 Год назад

Does the shared neutral issue remaine if your 12/3 red and black are going to breakers on the same phase like with tandem breakers?

@Galgamoth 8 месяцев назад

pretty sure the shared neutral was supposed to be on breakers tied together with a tie handle so they can't be on the same phase and that both hots go out together when tripped.

@lesliechow7286 8 месяцев назад

That’s how my dishwasher and disposal are wired and I’m remodeling and have wired it back the same way. 14-2 wire , two 15amp breakers tied together. Both appliances with a wall switch. I’m not sure why the dishwasher needs a walls switch but that’s how it was originally .

@extremekilla316 Год назад

Does this apply to 3phase 120/208 4w

@JasonW. Год назад

Scenario: A house built in 2000s housing boom era electrician runs 12/3 to a pair of 120v circuits for septic pump and septic alarm (both exterior underground). Using a double pole breaker would negate the alarm if the pump trips a breaker. Any work on this should have both circuits opened, but no exterior disconnect box was installed.

@MD-en3zm Год назад

Seems like a bad use of a MWBC.

@JasonW. Год назад

@@MD-en3zm I'd agree. Saved 40 in the wiring, will cost over 1000 to fix

@jessstuart7495 Год назад

I have a situation where I would like to rewire a light fixture to be on the same circuit as some other lights that are on a 3-way switch. I have easy access to the switched hot and two travelers on the 3-way switch, but no easy access to the neutral for this circuit. However, I do have easy access to a neutral on another circuit in the same switchbox. It is tempting to just use the neutral from the other circuit, but I know this is not safe for others who may be working on this in the future. I was considering using a current sensing relay to move control of the light fixture to the circuit with the 3-way switch, and still powering the new light fixture from the circuit I have a hot and neutral for in the box. Any suggestions? I would like to avoid tearing into the wall just to run a neutral to the switchbox.

@mychilpmr 10 месяцев назад

Hi sir...just a doubt.. If the transformer side nutral is not grounded, will the earth work as return path in equipment side...

@highvoltage1979 9 месяцев назад

@getmymail2676 Год назад

Because of the shared neutral topic, does anyone know what to do if your old transformer only had 2 wires (black/white) from my 1980's house into it? It sits in a plastic instead of metal box behind the doorbell chime. I do not see and bare/ground wire. Any suggestions? Thanks

@binkleyt Год назад

Love that whiteboard addition to the videos -- super helpful to see things visualized like that with the fast changes (less clunky than a real whiteboard..writing, erasing, etc...)

@tochia Год назад

🤔🤔🤔🤔

@ClutchTFS Год назад

They're called smartboards I had them in elementary and highschool pretty sweet!

@sotjonbixho3272 9 месяцев назад

😮😮😮

@danukepaintball Год назад

Those "You can't be shocked by a neutral" people aren't going to like this one either LOL

@thewiseguy390 Год назад

Open group and loose neutral hurt more than the hot lol

@dougfoster445 Год назад

@@thewiseguy390 why

@Vinka236 Год назад

@@thewiseguy390 I can confirm this and it does hurt like hell.

@Sandman206 Год назад

Confirmed..it hurt.

@kyle3694 Год назад

Only a dummy is a the reason for someone being shocked by a neutral wire bc a neutral being wired improperly would cause that to happen. Which would be due to a dummy improperly wiring the neutral. A properly wired neutral cannot shock you.

@johnsaake2303 Год назад

one thing I was taught when taking apart joints is to break the hots, neutrals, then the grounds; and the opposite order when putting joints together. That and keep your boots on the ground and your idle hands off of metal boxes cans or cabinets. Both are good habits to form alongside not working energized whenever possible

@lglubbock7593 Год назад

boots on ground?

@mackellyman5642 8 месяцев назад

One of the best comments.

@danhardhat2 Год назад

Single pole breakers are allowed on exterior lighting circuits with a shared neutral [NEC 225.7(B)]. NEC recognizes the voltage drop benefits of sharing the neutral because typically long distances are involved with exterior lighting and they recognize the liability of loosing multiple exterior lighting circuits from a single short if multipole breakers were required. So, extra heads up when working on parking lots and street lighting.

@barryomahony4983 Год назад

225.7(B) doesn't say anything about breakers, but it does call the multiple ungrounded conductors a "circuit" (singular), as in a multiwire branch circuit. 225.7(A) says outdoor lighting circuits shall comply with 210; including the handle tie requirement for MWBCs. Something of a moot point now since 226.7 has been deleted in the 2023 NEC; it was an unnecessary section IMO. But yes an extra heads up when working in those locations; a common danger is the lack of EGC.

@danhardhat2 Год назад

@@barryomahony4983 You're right...2023 NEC has deleted the exception that permitted the shared neutral for exterior lighting. There are many municipal lighting systems that use the shared neutral...It allows street lights and the seasonal lighting receptacles on the poles to run at 120V, and have each pole stagger circuits so if there is a fault, only half the lights would go out, which is much less dangerous for drivers and pedestrians. Now without the shared neutral, the conductors will go from #6's to #2's and have to run an extra neutral. And there will be current on all the neutrals, wasting energy (about 1.5% wasted energy - not much but still less efficient). I disagree with the NFPA - there are many good reasons for that exception for exterior lighting in the code.

@alhawkins3376 Год назад

Its not just exterior lighting but where you have sensitive equip. like a lab, just removing the neutral could fry whats on those circuits, even cutting circuits off not together can also do it.

@professorg8383 Год назад

@@danhardhat2 Well, I'll have to reread this but I didn't think it prohibited these shared neutral circuits. These are completely safe circuits and quite useful and practical for long runs. Not very common in regular residential wiring. These used to be quite common in long agricultural buildings and shops. As you point out, there are applications of this that make a lot of sense. I tend to look at it this way, what properly trained electricians would think it OK to spilt a two pole breaker into single pole circuits??? I can kinda see a DIY homeowner not understanding, but then I have long advised against electrical work as a DIY skill. I blame the internet for convincing people that they know what they are doing, when they clearly don't. What makes it even worse is all the stuff posted from 240 volt countries like "this is how it works everywhere in the world"!!!! It just confuses the hell out of DIYers. wh really should not be doing this work in the first place!! Does anyone in their right mind consider DIY surgery?? IDK, but I'm guessing that most people realize that the consequences of not completely understanding or doing something wrong, might be fatal. But working on electrical without fully knowing what you are doing, can have the same kind of fatal consequences.

@jameshunt5316 6 дней назад

⁠@@professorg8383not trying to be that guy but most farmers do DIY surgery on their livestock since the cost to have the surgery done at the veterinary clinic is often close to what the animal is worth. Either way you are going to lose the animal, might as well give it a shot. I assume it’s the same for people who want electricity in low income areas. Many countries make it nearly impossible to live without electricity anymore so I assume it’s out of desperation. Most people would prefer to call an electrician or a surgeon for everything but many people can’t afford either.

@drband8181 10 месяцев назад

Great explanation. I came searching for why I got a shock from a neutral when the breaker for the circuit was off while installing a LED power supply in place of a light fixture. It was a shared neutral situation I found out here! Something new to watch for. Thanks for the info!

@kkalafus Год назад

The most basic question that I wish the video spoke to is, how do you know if there's a shared neutral? Inside my panel I saw red wires used for 120 v circuits. That caused me to trace where the wire was going, which was Romex that also had a black conductor from another circuit. I hadn't seen this before and ended up learning more about it on your channel. IMO it's crazy that shared neutral circuits are allowed in residential construction because over the life of a home, someone can easily rearrange things in the panel in a way that's unsafe. In one of my circuits, someone had put the red and black wires on the same phase and ended up with double current on the neutral, which was a fire hazard and had to be fixed. Our home inspection missed this issue.

@danielherman9483 Год назад

Not an electrician, so take this answer with a grain of salt, but the only way to somewhat know for sure is to open the panel and trace the wire for the circuit that you're working on to see if it's something like a 14/3 or 12/3 (and then double check that they're on different phases like they should be). Even then, you have no guarantees that someone didn't do something insane like tie neutrals together from different circuits if there are multiple circuits in a junction box. If you didn't wire it yourself (meaning you're not 100% positive how everything is wired), just take the 30 seconds to put your meter on each wire to see if there's voltage. Btw just because the wire is red doesn't necessarily mean anything at all - 14/2/2 or 12/2/2 is a thing, so a single piece of romex could have enough conductors in it for 2 full circuits with no shared neutrals, but there may still be a red wire present there.

@JPLaJeunesse Год назад

Usually 2/2 wires they indicate with a red mark on the neutral with the red and black mark on the neutral with black

@weavercattlecompany Год назад

I've got a degree in electrical engineering so maybe I can help. You won't know! Also, it's not going to be an issue unless you mess with the point where the neutrals are tied together or in the circuit breaker panel if the other breaker is still on! Best advice from someone who have 30 years experience, just turn the entire circuit breaker panel off if your not sure about how things are wired. You could also use a tone generator to see if the neutrals are shared. Fluke Pro Probe 3000 toner, there are videos on RU-vid how to use this tool 😉

@krakenwoodfloorservicemcma5975 Год назад

Home inspectors aren’t usually electrical professionals. It’s not their job to get in to the nitty gritty of the panel.

@HaffDeadFred Год назад

Great thing for me to learn about ,we just did a panel upgrade for a customer and the inspector wanted me to “handle tie” all ckt breakers that share a neutral and zip tie the neutral wires together to ID them

@alphasaiyan5760 Год назад

Exactly. Breaker handle ties 👍

@trebochet 7 месяцев назад

Yes Multi wire branch circuits , and don't zip tie them. Tape them at the panel all together with an identifying tape color if you have several similar circuits , make your inspector happy 😊

@GS-lh2nx Год назад

Aka multi wire branch circuit? I have some of these in my 70's home. It really threw me off as to why I had 240v circuits feeding 120 volt devices until a friend explained it to me. Excellent video as always. Thx

@Sparky-ww5re Год назад

Not only have I gotten bitten by a neutral, when I was a teenager I got shocked off an electric water heater. Changing out an element. Uncle Gary turns off the breaker and tells me it's off. Of course I verified the power was off with a multimeter that I tested on a known live circuit. I tested across the terminals on the upper thermostat, but didn't think to check each leg to ground. What happened was there were two single pole 30s in the panel which has been there since probably the 50s or 60s. If memory serves me right the two 30 amp breakers were not even near each other, just randomly placed. Talk about some shady work.

@drewwassel3367 Год назад

One potential way you can get shocked from a neutral is if the breaker is off but there is a device with a large capacitor connected then it could energize the circuit

@tnspnk3 8 месяцев назад

Lol. I shouldn't laugh, but somehow it just seems funny. Capacitor's 101: Q: How to discharge when the neutral is cut. A: Insert random electrician for path to ground. :)

@jasonirion6664 Год назад

You can melt that neutral wire like a candle if both positive wires are landed on the same phase. If they are loaded up double the amount of current is returning back on that neutral. The breakers won’t trip but that neutral will fail spectacularly. Maybe a video should be done on this because it is easy to make this mistake. Keep up the great work !!

@docferringer Год назад

He's got that nice "teaching wall" that has demo outlets and panels, so he could use that. I say New Years is a great time to light that firecracker!

@lloydmills9619 Год назад

Positives huh.

@freddybee4029 Год назад

@jasoniron6664, I think you need to stop watching youtube video’s, and go to a proper schooling, to learn the difference between ALTERNATING & DIRECT CURRENT applications.

@GreasyReecey Год назад

Hot, not positive. Also, it's actually difficult to make that mistake because a 2 pole breaker connects to adjacent bus bar tabs that alternate phases. So unless you go against code and use 2 separate nonlinked breakers and install them with a gap in between them or an odd number gap in between them and land on the same phase, this problem wouldn't happen.

@mikejohnston179 Год назад

@@GreasyReecey Enter home owner re-arranging the breakers in the panel, so they are in a more logical order. "Why are these two kitchen breakers linked together? That's dumb. I think the breaker for the microwave belongs between these two."

@network_king Год назад

Other danger i see is if on and remove the main neutral then you have 240V like you said but also may end up with the loads being wired in series. Series in theory each would get 120V but it would depend on the current draw of those devices. The larger draw would pull more voltage but could also fry the other device due to drawing too much current through it. This is also why when I work on even dead circuits I splice things in this order Ground, neutral, hot. That way you are really only exposing yourself to the hot potential once as oposed to splice the hot then the neutral. Ground first just should there be issue and sometimes for small fixtures it is a nice anchor point to hold it till you can get the other wires linked.

@TomCee53 9 месяцев назад

Your basic logic is sound, but I think you’re confusing voltage and current. The larger draw would get less voltage. If you run a 60 watt bulb and a 100 watt bulb in series across 240 volts, the 60 watt bulb will see 150 volts and the 100 watt bulb will see 90 volts. (Ohms law).

@jimlangley840 9 месяцев назад

I know of a journeyman that became the neutral on a 277 volt lighting circuit, it knocked him off a 12 ft. ladder and fried his brain.

@traog 7 месяцев назад

In cases of a shared neutral it should be connected to a load with a pigtail so that if the load is to be disconnected the neutral connection isn't being opened. Some of the older buildings I work in have 120/208 3ph panels with 3phases sharing the same neutral, I see it all the time non pigtailed neutrals at receptials and lighting ccts it can be a challenge to determine which 3 ccts are involved.

@Bryankrall8090 Год назад

Share neutrals are like plumber's girlfriends.

@knucklehead83 10 месяцев назад

That was an Aha moment for me. My question is this: Wouldn't you be faced with the exact same situation regardless of whether the neutral was shared or not? Say you have 2 neutrals in a single junction box from 2 separate circuits. You drop the wire nuts on both of the neutrals an pull them out of the box. You would have 4 neutrals that have potential if you cross any of them. Two pairs with 120V potential, one pair with 240V, and one pair that is 0V. Right? So maybe the shared neutral isn't the problem, it's the shared junction? And only if the circuits are from opposite legs in the breaker panel. Right? I've been hit by neutrals before, and I couldn't figure out why. I think I get it now. Another question: I do continuity tests in rickety wired houses to try to figure out what the what is going on. At times, I will have 2 hots that will give a sort of buzz instead of a good clean high pitched tone. Is this because they are 2 circuits on different legs of the panel?

@AaronSchmid1 Год назад

We installed multi-wire branch circuits on the west coast well into the 2000's. Once arc faults started being required in more areas is when we moved away from it. So expect to see it in houses up to 2008+.

@johnbeckwith1361 7 месяцев назад

If I want to power a workshop and I installed a subpanel with ground and neutral going back to main panel. Wouldn't every circuit I add on that subpanel be a shared neutral?

@barryomahony4983 Год назад

3:26 You could still get a mild shock from the upper white conductor if you touch it while grounded; a small portion of the return current will flow through you.

@tnspnk3 8 месяцев назад

Good point. But I'd say "could" not "will." While many things are fairly straight-forward, this would be complicated. Depends on a lot of factors, like how "grounded" are you and possibly where you are along the circuit path. Not to minimize the danger; I sure as hell wouldn't touch it.

@HoosierRallyMaster 8 месяцев назад

Absolutely! If your body is providing the path to ground, then that "stub" white will all-of-a-sudden have current in it.

@charlesmcadory8286 Год назад

Killed power in the room that I'm install canless recess lights in. Get done everything went well except that neutral hog melting my lights. Mark your wires and don't melt my lights.

@brianrhodebeck6465 7 месяцев назад

I'm not in an electrician but don't be part of the loop That's what I was taught as a carpenter and welder Like your videos

@phildegruy9295 Год назад

Super good video. It is good to instruct the helpers/apprentices to be very careful in old houses and make it a requirement to turn everything off at the main before working on any circuit where the neutrals will be broken apart. One for safety and two to keep from blowing random things in the house up from open neutrals. Bought an older house and discovered that every single 120v circuit in the house were ran in a loop of conduit (from and back to panel) with a junction box every 10'. The circuits had 4 neutrals total from the panel and every neutral was half ass twisted together as no wirenut would fit with a piece of tape for cover at every junction box. Honestly don't know why the house had not burned down.

@csimet Год назад

Great explanation, as usual! I ran a new 2-pole 20A breaker with 12/3 dedicated line for my shop table saw, splitting the duplex 5-20R receptacle into 2x 120V 20A with the shared neutral. It is so I can upgrade it down the road to a 220V 20A simplex 6-20R receptacle when I upgrade my table saw from 120V to 220V. In the mean time, it provides the saw's 120V and an extra outlet for some lights until then. The key thing is it all ties back to that 2-pole breaker so both "legs" are shut off and never just the one. Hopefully this meets code... chime in if not please!

@web1ece 8 месяцев назад

I'm planning on doing this in my shop as well... I'm not sure why if it was on a double pole breaker that it would be a problem

@raymondsciara 7 месяцев назад

Awesome video. I want to take this opportunitty to say thank you Dustin for this great content in your channel. I passed my Journeyman test in August 2023. I would not have done it without your videos and all the help I got along the way from knowledgeable electricians that went out of their way to make sure I understood theory and field practices. I want to learn more stuff. I am currently working at an industrial work area. I am still a bit intimidated by the environment, but the experience I am gaining keeps me motivated. I have learned that failure is apart of the learning experience. I will never let past and future failures keep me from trying my best as an electrician.

@robertshivers7156 Год назад

question on any kind of 10/3,12/3,14/3 aren't the hot conductors supposed to be landed on a 2 pole breaker to keep you from getting shocked off the neutrals?

@marvinostman522 Год назад

I don't know if this what I ran into or not. I was working on a dishwasher and shut the breaker off and checked the "hot" to the "ground. No reading on meter. Went to pull the wire out and got a shock. I started checking everything I could think of. I finally found I had to shut a second breaker off to completely kill that circuit. I notified the homeowner and told them they needed to call an electrician to get that made right. With everything hooked up everything worked the way it was supposed to. Any thoughts as to what I had. I am sure I'll get lots of repesponses that I should have "Red tagged" the system and walked away. My second question is; what is a "floating neutral?" I have worked several places and other techs would come across a circuit acting weird and they would say "must have a floating neutral." I would ask theses guys how they knew that and how do find it and fix it? Never got an answer. I have sent this comment to several tutorials but never got a reply. Can anyone help me?

@bdetexas2269 Год назад

was 2 circuit setup w shared neutral as you found 2nd breaker needed to kill all wires... typical for kitchens to have 2 circuits 12/3 shared neutral often sharing DW with disposal. Always check hots and neutrals to ground before messing with 'em. I believe floating neutral refers to "broken" or "loose" neutral such that your hot back to panel voltage reading is less than 120v, the circuit is nonetheless trying to complete the loop by way of induction/other less conductive paths...some devices may actually still function somewhat on lower voltage (80-100v).... likely a loose neutral wire in any jbox along the way or loose screw at the panel.

@RXapples Год назад

In an EMT wired house, would it be overkill to label the white neutral wires that are in a junction box ? For example: a label that says "circuit 8". Are there ways to test if a white neutral is being shared between 2 circuits ?

@that1electrician Год назад

I see guys do that all the time. It is a great idea safety/ troubleshooting wise. I'm industrial and a lot of times 1 production line will have 5 or more control cabinets, all with their own control power transformer. People will jump in there all the time and borrow any neutral they see because to them, white means white means neutral. We started tracing out all the neutrals and labeled them to which transformer they return to. Another thing is making sure all your CPTs are phased correctly on the 480 side otherwise you're gonna get some really weird voltages between different CPT secondaries, and taking a hot from one and a neutral from another could be catastrophic depending on what you're trying to power up. But I digress.

@PhinAI Год назад

Important to think about during ballast replacements in 277V applications in large rooms with rows of lighting fed by multiple circuits. I'm sure there's nothing like having a hot neutral fall off of the fixture your working on into your ear or eye while standing on a ladder.

@docferringer Год назад

277 is a bit harsh for beginners. Start 'em off with a 120V lighting circuit with the switch on the neutral side, then leave them unattended while the old "I turned off the switch do I really need to turn off the breaker too?" argument plays out in their heads.

@jimcapino1667 Год назад

I am laughing tonight. This just happened to me. I work in Pepco substations. These people follow no rules. We have hot red, white,green, and black. I opened a circuit and checked for power. Fellow electrician turned on a different set of lights , on the other side of the building. I got a nice tingle. Got my meter and yes 120 at neutral. Shared neutral seems worse than just getting hit by black. Thanks

@workingshlub8861 Год назад

i label shared neutral or mwbc on every box and breaker etc......

@thebluebellschoolofdance932 Год назад

First off, thanks dustin for making these videos. Extremely helpful. In addition to what you explained, it should be noted that a multi branch circuit(shared neutral) should be on separate phases. Never coming from the same phase! Keep on spreading the good word my fellow sparky.

@DubG89 Год назад

Can you do a video on what is on an electricians truck? Please

@AnitaBonita46 Год назад

A one-bedroom apartment was divided and converted into two studio units. I am unit A and my neighbor is unit B. We both have been living in the property for 4 years. A couple of months ago unit B has been having trouble with his outlets. Which affects my bathroom lights. Landlord refuses to fix the problem. And Unit B refuses to get extension cords and fix the problem as well. I am being forced to either give unit B a key to my unit in case I'm not home to access the circuit breaker. Or landlord threatened to evict both of us, if we don't work together in regards to this issue 🤷

@wolfman_jagermeistro8445 6 месяцев назад

Report him.

@paulmac3307 17 дней назад

Sue the landlord immediately with an attorney's letterhead.

@AnitaBonita46 17 дней назад

@@paulmac3307 ended up being that unit b was doing it on purpose cuz he was behind on his rent. Told the landlord he's moving out because I'm a bad person. 3 months later a new tenant move in and I haven't had that issue again. 😆😆😆

@noneofur300 Год назад

I'm so sick of hearing about the damn politics. It's nice to watch something optimistic and fun

@KameraShy Год назад

And informative.

@perryallan3524 3 месяца назад

Great explanation... I'm a homeowner who was taught by an electrician in my youth on how to wire houses and all kinds of electrical safety items - and went on to become an Engineer; but still do most of my own wiring. Unfortunately I live in a 70 year old house (just a few years older than I am). While I have rewired the basement the plaster walls in the living areas are too nice to open up the walls and redo it. In my past I have dealt with 2 houses with nob and tube wiring among family members.... Assume everything is live unless a test to ground confirms otherwise (and you might have to run a cable to a bathroom or the basement to have a good ground). I rewired both of those houses starting with having an electrician install a new breaker panels and me doing all the work past that (and yes there were building permits and I was inspected multiple times). Interesting story is that in one city the electrical inspector came in to inspect my brothers new large 2 car garage wiring which I had done for my brother. The inspector recognized me and said he was glad to see me as my work was always 1st class. In this case my brothers old original very solidly built 1 car garage had been moved a 100 ft or so down the alley to ladies lot who did not have a garage and there was only room on her property for a 1 car garage (reused the old garage). So this lady was really happy to get a garage for just he cost of a cement slab and anchoring my brothers old garage to the slab. During the wiring inspection of my brothers new garage this lady came over and talked to the inspector about her desire to get her garage wired but could not afford the prices the electricians quoted; and did the inspector have any advice or options. The inspector asked her if she knew me to which she replied "of course - he's been helping his brother on his house with a lot of things." The inspector then told her that if she could convince me to do the work that he would approve it. Technically, he should not have done that. In my State a person can do their own wiring as long as proper permits and inspection is done. A person can assist an immediate family member as well. But my understanding in my State is that's where it legally ends. I thought it was a nice complement. She was happy even though she had to dig and fill in the trench for the underground service to her new garage.

@chrislester3152 Год назад

Hey I think your videos are great for beginners and I think you have a great way for normal people to understand things, I’m hope you could help clarify some more about two hots one neutral, because of the video about running cross overs from 120 volt generators, to a panel . So I’m wandering about wouldn’t that be same as adding the Amps of all the loads the generator pushes and would it double the amps on the neutral back to the generator, Any thoughts would be helpful and thanks

@terryuland6502 7 месяцев назад

Thanks! I have a ton of shared neutral circuits that do go to j boxes but I've always been in the habit of shutting off all circuits that enter a box prior to any work. However I didn't realize the code called for common trip on shared neutral circuits, thanks for pointing this out! I'd like to read more about that in the code, do you know what section this is in?

@TCAPChrisHandsome Год назад

I'm not an electrician, but I have done some electrical work, because my state is pretty lenient with that stuff. However, my rule when I fool with anything electrical is to shut off as far back as I can without it being a problem. For example, I had to change my dryer plug awhile back, I flipped the breaker labeled "dryer" and I tested the plug, and it still said 120 volts. Someone had something wired wrong, and I didn't know where the other line for the dryer was, and I still don't know what the second line on the dryer breaker went to, so I just had to kill the whole house, just to change one receptacle. That's the fun of living in a 30 year old house trailer, that God knows who has lived in before you.

@austinmckimmey8566 14 дней назад

This is so helpful. I’m glad I stubbed upon this. I’m trying to figure out why there was a 12/3 coming from maybe the panel. Going to a bathroom and office.

@1forthefacts254 Год назад

What about grounded neutrals and shared neutrals on a CAFI and GFCI breaker? This house was built in 2019 and has more that 15 of these.

@heroknaderi Год назад

Wow that is intersting To know thanks.

@bshane81 2 месяца назад

At my house I received a shock from the railing of my garage door. I'm planning to fully rewire the garage, but I'm curious if someone can identify exactly where the main issue is. Turns out I have two circuits ran through BX into the garage with a shared neutral. Measuring voltage at a receptacle(circuit #1) I have 120V hot-neutral; but 170V neutral-ground and ~25V hot-ground. The second circuit powers a light. The lightswitch box is metal, and is screwed onto the metal mounting bracket for the garage door. So I completed the circuit from the garage railing (and thus, the BX) to earth and received a shock. I assume the BX is not acting as a proper ground back to the panel, due to poor fittings/age of the system. What would the other open wire be? Is the hot wire on circuit 1 in contact with the ground?

@kjellg6532 2 месяца назад

Be aware! This video only applies for North America. Most of the World is now running 3-phase 230/400V TN-C-S mains systems in domestic areas. Higher efficiency and much more safe.

@potatofarmer 9 месяцев назад

There is a strip in every panel that has all the neutrals attached to it, and then is bonded to the ground bar. All of them share the same destination no matter what. Even if all breakers are open all neutrals, are still sharing the same potential. If you have a hot white wire, you have a hot white wire, electricity does not care about wire colour. Test before touch, or get a surprise.

@svinnthefallen1486 Год назад

Sawmill tech here. You should cover ground loop when dealing with a short to one side of a "space saver". I had a light switch cover plate that had 110v to ground after removing it from jbox. And the switch was. In good working order.

@MrKen59 Год назад

Reminds me of switch loops and the measures electricians used in the 80’s to combine wires to save a few feet. Navigating the branches in a home from this era is a mess - fortunately they didn’t play the shared neural game in my house. On a side note - one example of a shared neutral application today would be to a main lug sub-panel.

@leofortey7561 7 месяцев назад

Solution: Double-Pole breaker. You don't even need more space, you are already using two singles. In fact, if it is a Siemens or Cutler(and maybe others) you can use a quad and gain 2 more single spots after using the middle double for that 12/3(or 14/3) line. Don't just 'live with it', FIX IT! Anyone (home owner tinkering) on wires after a certified electrician was in there and did not fix it, is liable for people who get electrocuted. Cover your a$$.

@RandomAxeOfKindness 6 месяцев назад

Anytime you're working on old wires, do not trust the wire colors, no. If you do enough remodeling on a couple of old houses, you'll find something wired wrong. Personally, I did not realize the 240V issue described here was possible. I'm not a pro and (perhaps consequently) I'm really paranoid about getting shocked, and I blew up a 120V tester when I was checking neutrals in my bathroom. Which was alarming. So now I have a 480V tester and wear safety goggles if I'm not 100% sure all the power is off. (My bathroom had one light that was on the kitchen's circuit breaker, as a surprise.)

@nlee5034 10 месяцев назад

OH!! I’VE GOT A SCENARIO FOR THIS!! An “old timer” electrician, told me that if he had to troubleshoot a problem (‘emergency service call’), and he found a lost neutral, to just “find a neutral somewhere else… easy problem fix.” Yeah… while that would technically solve the “no power to a circuit” issue… it creates a whole other set of problems.

@B29guy1 8 месяцев назад

LOVE your information!! LOVE your insight. Thank you for all that you do. Since the 1960's, I have been repairing vacuum tube electronics. The very main thing to do is to isolate the hot to common by replacing the "death caps" and installing a polarized plug. I like the 2 prong that only fit pole outlets. I get many comments that I am wrong by not using 3-prong, however, I do not want to ground the common at the outlet. Am I wrong? Should I be better by using a 3 and leave the ground prong open? Is the 2-prong polarized still the best in your opinion? (I'm sure that the common is energized regardless of what plug is used, anyway). THANK you MUCH!!

@JackA2430 6 месяцев назад

What would happen if those 2 outlets in your video were dual function GFCI/AFCI outlets, on 2 separate breakers without the breaker handle tie? Would it cause any issues with how the GFCI/AFCI outlets handle a situation? Would the GFCI/AFCI outlet function properly? TIA

@cwalton56 6 месяцев назад

40 years ago, the Contractor I worked for used lots of Edison circuits in new homes we wired. Another electrician I worked with told me of this very situation where he got shocked touching a neutral wire.

@immrnoidall 2 месяца назад

OK now I scared. I remeber a 2/10 with ground, was run into a new laundry room to hav 2 different single 20 amp outlets. I was the last run of a rewire and they were out of the 2/10 w ground. so he ran the 3/10 from 2 separate legs of the box. like a 220 , but with 2 outlets instead. there is not a 220 breaker but 2 singles side by side.