Two comments that might help people: First, the key idea is voltage drop. Imagine a simple circuit that doesn't even have a switch. You attach hot and neutral to a simple lamp base with a bulb in it. This isn't realistic, but it helps get the idea across. The voltage on the hot terminal will be 120V. Current flows through the resistance provided by the bulb and this resistance causes the voltage to drop across the bulb. In fact, it drops 120V and the voltage on the neutral terminal will be zero. A voltage drop occurs ONLY when current flows. If you disconnect the neutral from the lamp base, current stops flowing. Therefore, the voltage drop across the bulb becomes zero. The terminal from which you disconnected the neutral is now up at 120V. No current is flowing, but the terminal is at 120V, ready to bite you. This is what happened in the circuit in the video. If you open a neutral in a circuit with current, you stop the current. All the voltage drops upstream of where you opened the neutral become zero and the voltage of the neutral on the conductor coming from upstream will go to 120/240 and the other neutral (heading back to the box) will be at zero. Here's the second comment: Never trust a neutral. Here's what I mean. I had to replace a pigtail in a lighting outlet. Before making changes, I checked for voltage, hot and neutral, found voltage, and then opened breaker. I saw the voltage go away, so I knew that I had the right breaker (since I saw things turn off). "Never trust a neutral," means that, even though I had taken all due care in identifying the proper breaker, when I untwisted the neutral splice to do my work, I did not assume I was safe. Good thing, because, as the neutral splice opened, it arced. How was this possible, since power was off, as proven by probing for voltage and killing the circuit? Simple. Someone screwed up. Somehow, they managed to tie the neutrals of two circuits together somewhere. So, voltage went off on the hot in the outlet when I opened the breaker, and there was no voltage on the neutral, but there *was* current in the neutral from some other circuit (who knows where) and, when I opened that splice, I interrupted that other circuit, the voltage drops went away, and the neutral in the splice came up to 120V. Never trust a neutral. Hope this helped.

I understood what he said because I already saw a video where somebody actually explained it in an easy to understand manner. Terry gets a C- for his teaching skills on this one.

A picture is worth 1,000 words. You showed us everything except the cause of the problem. When it came time for that, all we got was a verbal explanation. Clear as mud.

I'm not a certified electrician, but have been keeping myself educated. I first started when I was ten years old in 1964 by reading books at the library. I started fixing table lamps and other electrical things for neighbors and friends. I later got into electronics and started fixing home record players, audio amplifiers, and other things as well. This did work well for me overall as in 2006, I got a job at a company that built power control equipment for subways and light/heavy commuter and other electric powered trains. I was also able to point out design faults in the equipment we built, mostly when wires were too close to what are called load measuring resistor packs that would get very hot. They were wired in parallel to track circuit breakers and were activated in short bursts when a circuit breaker tripped to measure current flow to determine if the short still existed. Sometimes my advice wasn't taken and equipment would fail when put into operation. I also studied building codes before I rewired the bathroom and kitchen in my house built in 1913. There's still some antique light switches and old wiring using single wires and ceramic knob tubes in the house, but there's no heavy loads on those circuits. I've subscribed to your channel and hit the bell. There's always something I can learn from videos like these. Thank you.

being a good teacher is explaining complete details no matter how small or trivial it may seem

As a home inspector I appreciate your calm demeanor and ability to communicate that things can be corrected.

Very much appreciated. The average DIY'er often has very important things to understand about electricity, and certainly needs to take every precaution. Mistakes are often things that were never even thought of as possible, or careless oversights and assumptions.

Well, you explained it, but sped by the part about the splices. Might want to show that. Thanks.

Showing the upstream splice would be nice. Showing how to correct the problem. Thanks for your videos.

I’ve run into this quite often in my house that was built in 1930 with cloth wrapped wires and porcelain insulators.. started replacing wires and outlets and figured out it was easier just to cut out all the old and start at the breaker box instead of routing them back the same way originally done and avoided a lot of unnecessary splicing.

While working for a heating company years ago I got a late night call for no heat. I get there to see a fairly new warm air furnace and instinctively I reach for the power switch mounted on the side to see if it's on and to see if may have been installed up side down. (on being in the down position) On touching the switch box I was lit up like a Xmas tree because the whole cabinet was hot! Turn off the breaker and open the box to see lots of wires under one wire nut.... and the connection was burnt to a crisp. There was NO neutral and nobody had bothered to tie the ground to the box or cabinet. 15 minutes later I had trimmed back to good wire, added a second wire nut, and grouped the neutrals into bunches of 3 with a jumper, plus tied the ground to the box. Back in business. In hind sight, had they run conduit to the switch box there probably would have been a secondary neutral path via ground, but this was a Romex run from the ceiling to the unit WITHOUT a hard ground connection. In that case it may not have provided heat but I wouldn't have been blown to the floor with a hot cabinet. Did I mention this house had a dirt floor? All the better reason to have a good neutral and ground. I never did find out who wired this thing but now I always check with my inductive tester first.

I was having trouble with a TP Link smart dimmer switch. A Google search led me to this video, which was extremely helpful. It was great to see how to test the switch and eliminate problems. It turned out that I had the line and load wires reversed, hey both were black. Thanks for helping me out in a jam!

Thank you Terry for adding to my knowledge, I'm trying to install and automatic electrical switch for a backup generator. I'm not and electrician but I am an engineer and know just about enough to get myself killed. lol I'm trying to learn enough to survive this project. Thanks again. and just incase someone is wondering, the answer is NO I will not be doing a video explaining how to do this once I figure it out. It's too dangerous to share with the general public and as an engineer it would be irresponsible of me to share this information with unqualified persons. I am actually unqualified myself so I definitely will not be sharing it with anyone else, Sorry.

Great explanation. I've done electrical work for years but it never hurts to brush up on my skills.

Well explained and to the point, no stupid side jokes or useless back stories

Perfect explanation. Just went through this exact same thing. Followed my neutral wires and found where somebody had spliced them and they had come apart. Thank you.

Between me watching another electrical video before yours, then specifically looking for one about open neutrals (finding yours), I finally understand what's happening. I believe I've seen that open neutral light, on a simple 3-prong plug tester, at my parents' house on certain outlets as well as at switches. Not being an electrician, obviously, I'm sure it'll be fun trying to trace the direction the current flows from each plug/switch to the next. 😕 I do appreciate your video though and you making it easy to understand. Idk why but I'm very mechanically inclined but have always avoided electricity issues beyond installing lights, switches, and outlets. I created a mental block for myself. LOL Thanks again!

“So the answer is you have spliced up stream” What the hell does that mean? You explained everything well except the answer to our problem. I don’t remember splicing anything.

Good video. I always questioned why the industry calls the neutral a neutral. It’s a circuit return path. Think about it. There is no load below the bulb. And what does ohms law tell you? It relates voltage and current to load resistance. So with no current flowing back to the neutral bar, there is no voltage drop across your load. At least until you touch it in which case you become the return path! Watch those neutrals!!! Esp. On older service work. Often you find shared neutrals. Two breakers or circuits sharing a common neutral. Here you can back feed power into the dead circuit. As the dead breaker has no current path, it’s a recipe for getting a new hair do!!! Several times I have found several neutrals tied together with a massive solder joint and tape. Sometimes it’s OK, other times you may have a loaded neural when working on this. So always check that neutral! It will tell you instantly if you have a loaded neutral.

Great Job. Your knowledge was solidified in my book when you correctly called the neutral a grounded conductor. Not many electricians know the difference between a grounding conductor and a grounded conductor. So if the white wire is the grounded conductor and you break the conductor upstream the conductor cannot complete its purpose to take the voltage to ground in the electrical service through the grounding electrode conductor. It then becomes solely a current carrying conductor looking for a path to ground and preventing any current to pass through the load connected to it. So when the fellow touched the white wire he became the least resistance to ground.

I’ll never forget my first open neutral!

This is the best answer I find. The demo is superb. Thank you for the efforts!

Great video. Based on what you explained and some of the public comments, folks, if you are not an electrician, don't play with electricity. Mistakes will ruin your day... At best... I'm 11kV qualified so I do have clue...

I know this is old, but you are the only source I found to explain this problem! I was searching for a day and a half trying to figure this out.

Add a junction box between the panel and the switch. Then disconnect the nuteral wires in the juntion box to demonstrate the open circuit.

If he would of shown and explained it with an electrical diagram what is happening at lot of more people would underestand.

Watching the video second time and now I understand 120v not coming the light on, I had that situation where a guy kept saying it’s the light fixture itself or I was not using right the wire nuts a hard head person but this video gave me a good understanding to keep moving and don’t stay to long dealing with the light fixture that is not coming on even if you have 120v

Correct me if I am wrong... the neutral being hot is a result of backfeed from a common load passing back to an unbonded open circuit in the neutral... it’s also possible to blow up electronic appliances from a phase because of a non bonded neutral causing a 240v feed between loads. I learned on outdoor 120v branch circuits to use a double pole safety cut out switch disconnecting both hot and neutral as the neutral can have a different potential to grounds in the field which is a safety hazard even on circuits where the hot is switched off at the breaker. This is especially important when the circuit is brought to a location like a light pole or older commercial settings where ground potentials can vary widely.

My left ear learned something today.

Well it was good verbal explanation but not good visual in a circuit diagram. Schematic in electricity is were the rubber meets the road... This video needs more work with a point A to point B fault and remedy. Missing is what is upstream causing the fault. WIKI would say this article needs to be more comprehensive.

Hi and thank you for the information ! In our country - Bulgaria. The really old houses wirings, probably in the oldest lefted on villages houses has only two fuses for breaker for the whole house from the transformer to the everything around the house - one for the live wire and another one for the neutral, because couple of time ago in our country, the law requires only dual house wirings /with only live and neutral in the house, without ground/ and also - contacts with no grounding /the appliances manufactured then in our country was at law - double insulated/. So, one time i started diagnosing him, telling father to stop the fuse, and he misappealy take off the neutral one. So I wondered for a little why it has live on the both conducters even in the destributions on the wall /in the housing them in our area, it has destribution boxes in the walls before to go to every Individual outlet or socket. And there, the wires for the sockets and lamps are tied up together. I am figured it out suddenly, so that my dad has taked off only the one fuse - neutral one from my grandpa's house. Haha But here how it can happen dangerous faults !!!

Just another reason I don't mess around with electric wiring . I always call a certified electrician .

The more I study electricity the more I realize how much I don't know 😅

For the confused....checkout the diagram on his website. He explained it perfectly in the video but the diagram allows you to trace the path and makes it easier to envision. You can see where the path is broken so current doesn’t flow, but voltage still gets to the neutral. Touch the neutral and you complete the circuit.

I have run into this myself on a few occasions... SUPPRISE! While your explanation and demonstration was great, showing it schematically (as in a a diagram) would have been most helpful, as well as showing the opened up-stream neutral leg.

Yes, please show the splice that caused the problem. Other than that a great video, but without that additional information not sure how useful it is. Thanks again

You didn't show the main part!!

Why not show what happened in the box up stream? Also, with a plug in tester, it will show where the open neutral is, won't it?

I've been an electrician for 30 years and never heard of a "Loaded" neutral!!

If it helps to explain, that exposed splice on the white (neutral) he was showing in the switch box would have been open (un-done). So he wouldn't be testing a "neutral" any longer. Only a section of white wire between the light and the switch. Unscrew the light bulb and you wouldn't get ANY reading between the switch and the end of the white wire since the light bulb filament is acting like a "coupling" (connecting the black to the white at the lamp) and extending the black wire that brings power to the lamp. Yes, a diagram or more physical demo would help.

all current ultimately goes back to neutral and or ground rod through ground water back to power generation location. At substations there is a huge array of copper rods into ground to actual generator and or transformers. We installer alot of sub stations. Many do not realize all current has to go in circle back to lowest potential. Shalom

Have to agree. I had hot neutral and this video has left me even more confused as to why. Need to explain exactly what you mean by open neutral. Is it open that the panel or 'upstream'?

Grounded or floating neutral. Ha a journeyman electrician (supposedly) almost got me killed by floating a neutral feed into an outer building from the main MCC. Good explanation.

Thanks, this explains the theory behind half of my problem. My current issue is: Mobile Home with panel wired like a subpanel (bonding at the pole) Panel has 50 amp main breaker with 4 conductor pigtail to 4 prong plug Plug to outlet on pole protected by another 50 amp breaker/shutoff. Direct to meter/ power co. Power off at pole for all work😀 turned on for test only After scratching my head for the longest time, I disconnected all circuits (8) Capped off all hot and neutral wires, left all grounds connected. Tested main lugs Test showed 120 between ground and neutral just like your example but...... I also see that if I connect a test load (60 watt bulb) to any breaker if I switch the Load on I get 0 volts on the red terminal and 240 on the black When the load is off it is 120/120 Took the cover off the supply on the pole the neutral was burnt and open Explaining the 120 on neutral to ground. What causes the 120/120 shift to 0/240...? Thanks for the help

"He found that he had open splices further up the circuit". Well... that's fine & dandy. But... That really doesn't give you the actual reason why he had 120 on his neutral. People are gonna ask about those open splices further up the circuit, where the cause of the problem is. So what actually was the cause? For example, the same neutral, at the opposite end of the circuit might probably be connected to a hot leg. If that were the case, then you've given a reason why your neutral is loaded. If someone's sewer is blocked & wants to know why... the EASY answer is: there's a problem somewhere down the line. Well, no shit. The answer is with the actual problem, which everyone wants to know. Unless... I've missed something? Sorry. Don't mean to jump on your back. Thanks for taking the time to enlighten the uninitiated.

You need to show a diagram. The switch must be on, right? if the switch is turned off then no power should be at the neutral.

Helpful info, thanks. I have come across this situation recently. And this is the explanation I have been looking for!

Those open neutrals can be tricky...and deadly... I was called to a newly constructed home on a service call because the plumbers said they were getting shocked by their faucets... It took me a while but I finally tracked down and fixed the problem: The neutral on the load side in the meter base was never tightened at all...

My only question after watching this video is what is an open or loaded neutral?

Terry, Thanks for your videos. But,...As a retired industrial/residential electrician, "I" understand the situation. But people who really have no business messing with electrical wiring have no idea what you are talking about without you showing by example what caused it, rather than to just mention it. Without being rude, without that, the video is rather useless for the unknowing novice. Sorry, just constructive criticism. BTW, the worst messes I have ever had to correct is when people of such, mess around with 3 way, 4+ way switching. Totally screwed up. Novice people have no idea what NEC Code is either. These people also need to realize that they can screw themselves beyond belief from their insurance companies when regardless of being the home owner or not, as some jurisdictions still say that's ok. But MANY City charters say NO and have absolutely in no uncertain terms that it is not allowed. That you MUST use a certified electrician who will sign off and some as in the State of Tenn., requires a City Inspector to approve, before use. Some cities, such as Chattanooga, and others have city codes that are far more detailed and additions beyond the NEC. And of course you have to comply.

I also would have like to see what he did in the box! I like your videos because the sound and video filming are great with no camera shaking.

Thank you. I have outside lights on a store that show a hot line wire but no current when timer is switched on for the neutral. I’ll have to follow the circuit up stream and see if a splice has been disconnected. Definitely 👍🏻 and a sub.

I wish I could see a diagram of what happened..

i feel sorry for you Terry!... people it was an open Neutral!!.... he doesn't have to show you anything!! just imagine in your head the WHITE WIRES NOT CONNECTED!!.. that's all.. plain and simple.. if there not connected the circuit is open which means its not complete which means with AC you have to have a complete circuit or you will have no light! once he hooke the white wires back up the circuit was complete again.

You should provide a diagram in conjunction with demo, it would add clarification for those who may not get it from the demo.

I had screw in drywall penetrating cable black with white wires. Lights still were working correctly. I found out this, once replacing switch. Took me whole day to solve the problem.

In USA the plastic boxes don't have a ground strap on the screw threads, they should, like Canada, eh?

Do what I say not what I do. That's what I say to my apprentices. 😂

Thank you, my name is Patrick from Uganda, your video helped me.

A picture is worth a thousand words

Hello, Terry. My class and I watched your video and we had a question about circuits. We are currently studying single circuits and parallel circuits and we would like to know if there is no load, will the current still flow through the connectors (wires)?

Nice video but you didn't show the problem!

Great video Terry, I know what you mean, I have seen this type of work in Mexico, Brazil, and the Philippines. It can get dangerous, but they do what they can and get by. Best of luck with your new course - looks good!

Can I tell you thanks for the tips. I hate house wiring !!! I spent 2 days chasing wires on plugs and thankfully I found loose wires and or bad plugs which I replaced. What I didn’t expect was a ground that just fell off the post on a switch that had at least in my mind, nothing to do with the plugs that lost power !!! Blows my mind.

Wish there was a drawing

No solution. Down vote

As an early apprentice I recall being in the ceiling of a burger joint making connections bare armed, sweaty, on HVAC ducting. I called out to the electrician. Monroe, white wires can't shock you right? I should have waited for his answer.

EDIT: I changed my downvote to an upvote due to the OP reply. Terry: I would suggest you add a 30 second trailer to your video showing where the problem was in your example for all to see. A picture is worth a thousand words.

Terrible video - He never showed why the problem or how he corrected it.

Just had a similar situation. Outstanding explanation to an annoying issue. thank you!

my.. you explain things well Terry... Thank you so much..

I had a call that a 5 door refrigerated case was out. In this case were 5- 115v 9watt fan motors. I thought, why would all 5 motors go at one time. Took out my meter and yep, 208 volt going to the motors. Now this circuit was in place for sometime, and there was a renovation going on at this time. So I know this does happen

Enjoyed the lesson

Folks, the point is that if you don't shut off power before you pull the wire nut off and separate the neutrals you have just turned the neutrals into an ungrounded (aka HOT) conductor... It will light you up. And before the code change you could have several circuits sharing a neutral... 277 volt lighting circuits are notorious for it. So if the structure you are in is older, make sure you shut off all circuits that could potentially be sharing a given neutral.

Thank you for sharing your knowledge. Much appreciated.

Excellent video... Thank You!

Great Example sir thank you

You're the right guy to explain this but I think it would be easier to see if you drew out a circuit and showed a circuit working fine and then one with the open neutral

House wiring can be tricky to analyze from limited check points. But if you can keep in mind the overall circuit and source of the two points where you are reading a voltage and think about where it could be coming from (like through a load) you can figure most out.

Terry, us men are excited by visual display's whether it be a naked woman or electrical circuitry .. just gives us a better understanding of what were about or need to do .. words alone just leaves too many questions.

Thank you I get it. I had electric shop in HS and was in electronics in Air Force however in my late 70s. Alternatively I could use same wire size as to the present outlet to the heater hookup. The original line is long so there might be some line drop.

Excellent information,tanks 👍👍👍👍

You are good on talking and confuse people.

My left ear enjoyed the video. :)

Great video terry. Looks like you were in the sun...hope you won at golf..caught the fish ... yard work went great...it’s nice to see the sun.

without mentioning Amps and why they are present or not... this 1/2 useful.

Wow, and this is why in Australia you have to be licenced to do electrical work. Your "fault condition" was covered in our high school physics class and if someone working on electrical systems can't understand the same voltage & current flows through the whole circuit back to the power station they really should not be opening things up. It's not the live wire that will kill you, it is YOU forming the remainder of the circuit that does it. You could have provided a far better explanation in less time with a diagram, in my opinion.

I have some lamps where the neutral is not connected, but the ground is connected to the neutral wire. The neutrals also have power. I'm about to redo the whole apartment, breaker panel and every outlet. I think we should find the problems tracing everything back to the panel, or who knows? I'm also changing about 12 breakers as well because of the weirdness. I disconnected the neutral to the garage light and it works, so I have to start over.

I got 2 15amp receptacles on one circuit at my home. One has power from the breaker(4 wires, 2 white, 2 black and 2 grounds twisted together), it feeds other recep which has 2 wires and ground, 1 white, 1 black. The main recep works perfect, the fed recep only shows ground(119v). When I test the white and black, I got nothing, or really the multi meter shows like 1 or 2 or 0 or goes back and forth between those as I hold leads on white and black. When I hold leads on white and ground it shows 0. When I hold leads on black and ground it shows 119. The main recep from breaker shows 119-120 or so on both of the white/blacks. Ground on both black/ground. 0 on both white/ground tests. I;m able to do this testing on the bare wires as I took both the main recep and the fed recep off walls. It's now bare wires at both outlets, easy for me to test them. I can't figure out why the fed recep does not have anything when testing black/white. Black/ground has the right voltage, white/ground has 0. I put new recep at the main one that feeds the other recep. Didn't fix it. Same prob. At the breakerbox, this circuit's breaker is the only one that has the red test button on the breaker. Prob because these 2 are 15amps and both are on porches(covered porches don't get rained on, but outside nevertheless). The 2 outlets never had and still do not have gfci receps. They never had those type out there. Both of these outlets have always worked fine until about a year ago. This house was built in 1987 or so. It's in SC. I'm just Stumped here. The 2 outlets are on porch's in back and front of house. Porches are covered though. But still, they're outside technically. They both came with the house(not installed by any me or any previous homeowners). That's the trouble shooting and the work I did to try to fix the fed recep at back porch. The power lines don't go under house, in the walls and drop to receps. Man, not sure what to troubleshoot next or what to test, check, etc, at this point. Sucks too. I need that power at back porch's outlet. Could the actual breaker be bad? But then I think why would main recep work fine. Should the receptacles be gfci's? They never have been. They both used to be the older push in type and someone had changed that fed recep, at back porch, sometime before I bought this house about 10 yrs ago to a newer type, not gfci though, and it's worked fine for past 9 years. No mice here, rats, rodents, etc. It's crawlspace, brick, not mobile home, no issude with electrical since I've been here. Clean house. No rot, trash, yard growth, in other words it's just a regular decent house, not anything spectacular but not anything nasty or neglected. That front main recep was the old style still and I just put that newer type recep in it's place to try to back porch to work. In other words I took the one from back porch and replaced old push in style main one on the front, wired all 4 wires to it, left the 2 grounds twisted like they were, to get the old style out of the circuit- still same issue at fed back porch recep! This sucks. Can a whole entire white neutral wire just go bad, like from the main recep to the fed recep? Ughhh! I know I've done the trouble shooting correctly, I know no matter what the balck/white show nothing, the black/ground show 119 or 120 or so, the white/ground show 0.

Great job

The problem in this explanation is saying the neutral splice is open "further up in the circuit." Which way is "up"? He should have said that the neutral was disconnected/open "closer to the main circuit panel" (where the neutrals all come together and are grounded).

The neutral or white wire was not in a continius run all the way back to the source (the panel) thats why the power went up the black wire after the switch thru the filament in the light bulb down the white wire and cut or disconected from panel

Since the neutral was open between the box and the panel, the 120v on the neutral to ground was because the light switch was on and it was getting the power from the hot, through the light, into the neutral, but then it had no where to go because the neutral was open. Shutting off the light switch would have unloaded the neutral.

The good news is that while the neutral is giving you a shock, the bulb should light up….

In other words the white wire (neutral) is not connected somewhere between the lightbulb and the breaker. Hence the term open neutral.

What he's saying is that the neutral is loaded because it is open. The path to "unload" is the neutral path back to the panel, which is bonded to ground. If the bonded/grounded/neutral conductor becomes ungrounded it is then loaded the same as the ungrounded(hot/black) conductors. Please correct me if I'm wrong.

I think 99% of use still scratching our heads. We need actual visual demonstration of EVERYTHING you talking about. The hard part of learning is understand what is what. Such as if you tell someone new to grab a 10mm wrench to loosen a bolt they will scratch their head and wonder "what the hell is a 10mm wrench and how it look like?"

love your diagrams.. you explain things very well... thank you for sharing,,,

I used to work as an electrician helper, once a circuit is complete, or on, the white wire becomes energized just as the black. The black, & white are both hot when the light switch is on, or something is plugged into an outlet receptacle. Often residue electricity can back feed into the green ground wire. I have measured 38 volts AC in the ground in my home. I connected a volt meter to the white wire, & ground wire, & got 38 volts AC.

Great video, thanks for the explanation.