You did it the hard way. You could have measured the voltage on each side of the junction. Should have been basically 0V. You had 3V there.

When the power goes out at night and we're all just sitting around thinking, 'somebody's working on it right now.', - this is the guy! Bravo Bob!

I learned about a loose neutral at a house I once owned. Every time I turned on a toaster the kitchen lights got brighter. I went to an electrical self help blog and a user said it was most likely a loose neutral. In the main panel I found the previous owner/builder had cut the neutral too short, bent the conductor to a 90 degree angle to get it into the lug, then failed to torque it properly. The aluminum wire had heated and corroded over time. I repaired it and the problem went away.

Hey all! I wanted to show a couple shots of this job because we receive flickering light calls quite often. There can be dozens of reasons as to why the lights are flickering but there are two main categories: - Loose "hot" connection. or - Bad neutral. It's important to figure out what exactly you're looking for first. A bad neutral can harm customer equipment, so it's important to rectify that problem before leaving. A bad/loose hot connection - voltage will always go down. If voltage goes up on one side, you have a bad neutral. it's literally as simple as that. That being said, there are the occasional transformer or tap changer problems that can result in high voltage.. If that's the case the voltage will be consistently high as opposed to high/normal as load is removed. ** I should have also show in that last clip, that if you check voltage across a bad connection you will see that 4/5 volt drop.

For anyone still confused why this happens, normally the neutral is referenced to ground, by being connected to it. So the neutral is the 0 volt point that the +120 and -120 are measured from. If the neutral isn't making a good connection it will be pulled above or below ground by the leg that has more load. The bad connection is basically moving the 0 point in relation to the 2 legs. That's also why the 240 isn't affected, they're still the same relative to one another. That's kind of an oversimplification, but its more or less how it works.

Love the troubleshooting very interesting to watch for me being a HVAC tech. I deal with lots of electrical troubleshooting so very interesting seeing others doing a different job doing other types of electrical troubleshooting.

We had this exact problem like 25 years ago in an old house my parents had. The neutral connection had basically rotted right off on the house side of the service drop. It was an old house so everyone assumed it was faulty wiring inside the house and wasted a day or two going through all the wiring in the house. In that time we lost a few appliances, electronic devices, etc. before one of us happened to look up at the service and see the neutral wire either wasn't attached or was barely hanging on. (I was young then so I cant remember exactly now.) Power company came out and re did the service connections and everything was fine after that. Great video as usual!

It's always nice to see voltage drop testing done in a completely different context. Ultimately it's the same lesson, don't expect to see much unless you get electrons moving.

This is amazing. My energy monitor claims to be able to detect this and I've always wondered how. Thanks for this amazing video

I had a failing neutral but it was on my side. Electrician came out, and recommended changing out the neutral, as well as the meter base, panel, and leads from the mast head down. Reason for replacement of meter base and panel was extreme corrosion on the neutral lugs. My home is 35 years old. After the work was done, problem was resolved. Emergency repair bill in Newfoundland, Canada April 2024 was $8k While the electrician was writing up the quote, he notice the lights dimming, so he put a volt meter on both hot lines in the panel. With only baseboard heaters and lights providing load, he saw a voltage difference between 100-150 volts. He immediately ordered emergency power shutoff, and work was completed the next day. 2 weeks before calling in the electrician, turning on the dryer almost caused an electrical fire on a power strip with only a Roger’s modem plugged in. At the time, I thought it was just an old power strip that failed. 2 weeks later, turning on the microwave caused lights to blow, then lights started flickering, TV shut off, and modem keep restarting. $8k was a huge unexpected expense, in an emergency situation. That includes an upgrade to add a surge protector at the panel, so I could have saved a few hundred dollars by not doing that upgrade. This work was to replace the existing 150 amp panel. If I wanted to upgrade to a 200 amp panel, the bill would have been over $10k. I almost fainted. lol. I still have 20-30 amps reserve in the panel if I ever need to do any additions, like a mini split. So there was no real need to spend an extra 2-3k. Probably could have got it cheaper by shopping around, but in an emergency situation with a reputable company with availability next day, I just went with it. Electrician did a clean install and government inspectors approved the work. Ed Budgell at Mr. Electric in St. John’s did the work. Super nice guy, answered all my questions, explained everything, and was very humble. He takes pride in his work, and wants it to look good too

I've been chasing some odd power issues at my place for a few years. I redid the breaker panel to balance the legs better and that helped a lot, but thinking back, I think one leg was going up when the other went down. Maybe it's been a bad neutral all this time. I'll have to check next time I'm back home. Never knew you could check for a bad neutral like this, but it totally makes sense why that would work.

This is a Job you want to make sure your Head is in the Game at ALL Times. Thanks for doing a Consistently Solid Job. 👍🙏

As a non-lineman homeowner my only experience with this was years ago when my lights suddenly got real bright when it was windy then returned to normal. Got out my meter next time it happened and I was getting 188 volts on that circuit. Don't remember what the other leg was, but it was quite low. Had to head to work, and didn't know what was causing it so turned off all breakers except my fridge before leaving. When I returned in the evening I saw that my neighbors line (triplex) was brand new. Haven't had that issue since.

Once my service totally lost the neutral, that can be very destructive to some of the 120v devices as the voltage can swing very unbalanced line to neutral depending on the running line to neutral devices. Thanks for the video and explanation.

The first house I owned had a bad neutral. Back in the days of incandescent bulbs, when the motor in the dishwasher started, a nearby lamp got brighter. Now, the challenge was getting the utility to make a visit. No one had lived in the house before i bought it, it had been the office for a few model homes. The neutral to water meter seemed OK, as did the neutral inside the meter pedestal, which i could open about an inch without breaking the seal. I called ComEd to report the problem, and of course, they wanted me to call an electrician first. I exaggerated my credentials, and told them i was an electrical engineer, while I had only taken a few Electrical Engineering courses as part of my Computer Engineering degree. This was enough for the person taking the call to dispatch someone. When i got home from work, there were no more lights getting bright as I ran the dishwasher. I know the utility wants to be sure the problem isn't on the customer side before dispatching someone, but that would have cost me real money. I did as much debugging as i could without pulling the meter.

Had a bad neutral in my six unit townhome building a few years back. I watched a number of videos trying to understand how to locate the fault but never found as clear of an explanation and demo as this one. Thanks Aaron! I called the power company who claimed they came out and checked the pad mount and didn't find a problem (I work from home and *never* saw a utility truck show)... Then called the HOA who called out the electrician. Never learned where the fault was, but I'm guessing it must have been the building main disconnect.

Nice video Aaron. Sometimes you can use a voltmeter across both sides of a splice connector and see the voltage difference. In your case it might have been anywhere from 1-10 volts. This can also work for a Main breaker or individual SP or DP or Three phase circuit breaker and fuses too. Stay safe!

This situation is all to common in old services in the USA.

Excellent troubleshooting instruction! I'm in the middle of doing something similar, but with a 24 vdc gas turbine engine air bleed control system. Done a lot of work with wiring on aircraft and jet engine test facilities over the past 43 years. It can be quite challenging, and often frustrating, but for some reason I still love doing it! LOL!

This is the type of content that makes your channel the best of this nature on KZfaq…

Excellent demonstration on how to find a bad neutral.

Fascinating video Aaron! I have ran into a few bad neutrals in my years as a telecom tech, and have actually seen telecom lines toasted due to that imbalance from the bad neutral finding its way onto low voltage wiring (typically toasting some comms equipment in the process!) Love seeing how that is diagnosed and repaired!

I recall seeing my first bad neutral at a house we managed -- Randomly, appliances in the house would start smoking without being touched. Voltmeter read fine, until I set it to hold on max, and then saw that it was briefly spiking to ~190. Was a windy day by the ocean, and over time the neutral loosed within the meter, most of the time making decent contact except during gusts. Love seeing your step-by step of diagnosing problems!

when there's a bad neutral, I generally find the CATV coax carrying current back to the street(scary!), especially when you find it's smoking hot, melting and carrying over 15amps of current. always clamp on ammeter test! don't go playing and handling it directly unless your geared up. I've also found current flowing back out city water supply lines via the ground bonding to older metal service lines. some buildings with the neutral completely ripped off and still working seemingly perfect, no signs of problems, stable voltages and nobody had a clue. other than I've started to check the alternate grounding paths by default.

With such a small gradient in values it's a wonder this isn't overlooked by many in the field! TY for sharing this!

I really enjoy everything you post. So much to learn.

Thanks Aaron !! I didn’t know it was such a simple trick to diagnose. As an electrician, I’m naturally limited how far back I can get to source for testing, but thanks to your teaching I can now confidently (and quickly) diagnose a bad neutral and decide if it requires the attention of the supply authority. Cheers !!

I'm an engineer who has worked on industrial projects my whole career. I pays to have electricians who understand wiring in an industrial facility. On my very first project a bottling/canning plant for Ocean Spray, yes I was very green, we had electricians who had only performed residential work wire the plant. Oh my. Hot neutrals all over the place. As in 480VAC hot. They couldn't read the drawings. It was that simple. And the drawings were just fine. I got the job of fixing all of their mistakes on the automation end of things. Really surprised nobody was hurt.

I love it - very well explained - clear and logical. I troubleshoot computer programs, and the thought process is identical, as different as the steps may be.

Just an excellent post and explanation of this. Thank you and be safe.

Well done sir. Your method was in accordance with power distribution troubleshooting standards and You taught it well. Thank you for not teaching it "the easy way"

OMG . I just had to troubleshoot this same problem last weekend. Your video and explanation were awesome. Wish i could have watched it prior. Now i know to really figure it out. Thanks

I learned something today! Thanks, Bob!

That neutral is wanting to take a long vacation from delivery of the proper voltage to the customer 😡😡

Great video. Very informative. Thanks Bob 😊

Wow, this was super helpful. I’ve never seen this explained so clearly. Thanks!

A great example of Kirchhoff’s law. I learned about it the hard way when the neutral in my generator inlet box became disconnected. Fried a few LED lights when I switched on an unbalanced load.

Thanks Aaron, another great video.

Great Video Aaron hope you had a good and quiet New Year's Eve. Great to see another video

This is one of those uncommon (but not rare) situations that homeowners need to be aware of.

You should be able to measure that ~4-volt difference across the bad connection on the neutral. That's an easy way to confirm a poor connection.

Your videos are always good. This was great! Thank You Very Helpful!!

thanks Aaron for very interesting video. 👍Something new was learned there. Had similar faults in the underground cable network recently in incoming to a property

We use a few tools made specifically for open neutrals. Arnett Super Beast to test the service voltage while load is applied without risking the customer equipment. We also use the Bierer ST800 to locate the bad connection location. I recommend looking up the ST-800 video. It's one of the best tools I've used in 20 years as a lineman.

I work at the local telco, and I probably run about 10-20 calls a year due to a BROKEN neutral line causing our coax service line to melt at our tap or at the ground block, since we bond to the ground. I'll inform the customer to call into the power company right away. I normally can spot the break! Now you have me thinking of what issues a bad neutral can cause for our internet customers. Have you ever seen this issue (melted coax) yourself?

Good troubleshooting lesson Aaron. 👍🏻

I really appreciate your professionalism. If I was 40 years younger, I would follow your path you make the job look interesting and almost fun other than it being work how was the firefighters for 33 years and had great opportunity to work with mini lineman they were great help at fires that involved electrical system. Not sure if you’ve considered this, but you would be an excellent educator, your company should be using you to train all the new lineman. Have a great day and keep up the good work.

Not a lineman, just a guy who likes watching your videos. I've seen this happen a few times. I was told bad neutral and the voltage swings were really crazy. 40v on one side and 200v on the other. Some people's stuff was getting really hot and smoking.

Unreal skillz.... At work we have a smart crew like skills you have. Really cool explanation.

Very interesting. Learn something new today. Electricity is a funny little monster so cute but has a bite. Thanks for explaining how to troubleshoot the issue.

I love a good diagnosis walk through. Hell yeah!!

Very informative! Thanks for sharing as always.

We have a tool called The SuperBeast that finds open neutrals….it takes the place of the meter and puts a load on the service….….It’s a troubleman’s best friend and it narrows down if its a customer problem or a utility probem….

Great video Aaron, it's not often we get to see you troubleshooting like this

The problem with turning appliances and other loads on u can burn appliances and other equipment up

Not that I would be fixing this issue myself, but it's great to know how a bad connection could cause a voltage spike. Thanks for the information.

Great troubleshooting! I’ve only ever had to deal with partial voltage losses, which can take some time to chase down. Sometimes it’s hard to call the cause when it’s intermittent voltage loss. I’ve checked a panel in a mobile home to make sure it was good at the service because they intermittently has flickering lights but only after their down syndrome son knocked a wall loose. According to them they hadn’t had the light problem prior to that but the issue they seemed to have was an outlet on the kitchen counter serving a microwave. I changed out some old old receptacles that I thought could have been the problem and the problem seemed fixed but returned and ended up being the lateral line feed from the source pedestal.

Reminds me when my neighbors and I lost one of the hot leads off the transformer. It was happening during the daytime when most people were not home. Because we were the only ones home, we thought it was due to the old wiring of the house.

I'd be worried about placing a large enough load on it to raise voltage to 150 volts, that sounds like enough to risk damage to devices or appliances in the house. (maybe enough to trip some sensitive surge suppressors?) And there are probably a few items here and there that could be damaged by applying too little voltage as well.

Great and very thorough work as always. Don't mind those in the comment section critiquing you for being thorough.

Just had first hand experience with this as a consumer. On the 23rd a squirrel managed to chew through the neutral coming into my house. I happened to be next to the breaker box when the light show began and flipped the main. The electrician saw the problem and I contacted the power company to get it fixed. According to the electrician with a fully cut neutral I had close to 250v on some of my outlets, fried my stove, fridge, and several surge protectors. Made for a fun christmas.

Very Interesting video!! I'm surprised you didn't talk about the customer's ground, (driven or water pipe). With a defective service neutral you will get return voltage on the house ground. (If it's the easiest return path) You could also amp probe the customer's ground. Keep the videos coming, very enjoyable!

GREAT VIDEO!

Like these raw videos!

Happy new year to you and yours

Nice explanation on that trouble shoot. Just looking at things really can’t show much. Test test etc. stay safe brother 👍

Great video!!!

Great video. Years ago I lived in the basement suite of a house where the neutral was damaged by corrosion and it blew out all of my electronics. I never understood until now how a bad neutral fried my stuff but if the actual line voltage changes it would definitely cook everything. All of the incandescent lights in the suite were glowing blood red (low voltage) and there was smoke coming out of my AV gear. Sucked. Some of it was repaired (not replaced) by the utility but was never quite right ever again.

Great video thanks for sharing

Very interesting - thanks!

Informative, good video !

Saw that on a service call out in the country. All the connections at the at service loop were fine but the dropped neutral was at the transformer. Called power company and it did not take long for them to fix it.

We use the Super Beast to test our line side neutral(HJ ARNETT SUPER BEAST-D HJA-469-SD SERVICE CONDUCTOR TESTER). You have to disconnect the line side neutral from the meter base socket and hook up the beast. If the beast runs at normal fast speed its usually a sign its good. If it doesnt run at all or very slow the neutral is most likely bad and the tell tale sign of unbalanced load is usually a good indicator as well.

We have copper water mains here... about once a year I'll put an amp clamp on the water main to make sure I haven’t lost a neutral, but also to make sure one of my neighbors hasn't either. The neutral is the most important wire!

When the current is really low like in this case, it probably doesn't take much difference to cause a noticeable voltage difference. If the house had been drawing 30A + 32A the voltage difference might have been in the noise. All due to the winding resistance at the Xformer. I like trouble shooting videos. A few months ago one of my UPS' signalled a ground fault. Took me many hours to find it. (Was in a ceiling light box at the other end of the house that also fed the bedroom end of the house where my office is). I figure that open ground has been there for many years. Only when I moved the UPS did I see the GF light. Hard to find, but easy fix.

Your videos have been a great source of knowledge for me, the way you stress safety is so important. Side note… how often do you find yourself installing service drops

When you apply load across one line and neutral, the voltage across the other line and neutral absolutely does go up since the impedance of the neutral conductor back to the transformer is normally much greater than the impedance of the transformer and it’s supply. The further you are from the transformer, the greater the effect.

Wish you worked for my provider. Had the same issue intermittently lights would get super bright for a moment then dim. Guy came out around lunchtime and said bad neutral no biggie which I knew was the usual suspect. Guy went to the pole and found what he visually suspected was a bad crimp. Changed it out and assumed it was good, didnt even say anything to us after, he just punched the meter back in and split. Problems came back quickly and it was getting worse so we called again and they sent the guy back out, now just after dinner. Finally put a meter on it and had 142 on one side and 109 on the other with power on. Decided it had to be at the service connection on the house, but now it was dark so he couldnt use a ladder without calling someone else because of the SOPs. Told us he wouldnt call cause the company doesnt like to pay a second guy OT. Say he can leave it or he can back across our lawn and use the bucket, but we have to sign a release for any damages that did to our lawn. Im a firefighter, and the thought of 142 volts with an older home and some things ive found from past DIwhy owners- and what i havent found and wasnt going to have it left that way. I did protest some and point out that he could have fixed it the first time and therefore asking for a second person or not asking us to sign a waiver wasnt unreasonable considering it was a safety issue and it was his second attempt. His response was to threaten to cut all power and come back tomorrow as a 'screw you', which he may have done had I not pointed out that we were standing in front of my ring doorbell and that as bad as all that would already look, and as much as I despise people who use it, there's law about cutting power when there's a disabled child that he would be violating. Amazing how fast he reacted to the realization he had admitted on video that he had made an assumption, not tested anything before or after and then found that he left an unsafe condition which he refused to ask for a second tech or not drive a line truck across my lawn to fix then topped it with a threat to cut my power and have no heat or water if I didnt let him tear up my yard to save himself getting chewed out by his super for needing the second guy... A second guy was rolling up 5 minutes after he called dispatch... Have had 2 TVs die and the power supply caps on the main board on a fridge burn out soon after...but im sure its pure coincidence...

Good job Aaron.

Great Work!! -Master Electrician (inside wireman) from Wisconsin

Really good description of the problem and diagnosis! Did you have to cut power to the home in order to change the neutral clamp? (I assume yes)

Be safe! GOD bless you ALL.

A long time ago, early 1990's, living with my parents, every so often the lights would go brighter or dimmer. Sometimes they would get so bright the 100 watt incandescent lightbulbs would POP and I would have to use a potato to get it out. JUST KIDDING! I turned the power OFF and took it out safely. Often, our floor model TV's built in circuit breaker would trip. When I took transformer power transmission theory and they taught us what happens when a neutral is loose I realized what was happening. One night it happened and my bedroom light became REALLY BRIGHT. I grabbed my Fluke 73 True RMS multimeter and checked the voltage from neutral to line at my receptacle and I measured 194 VOLTS!!! 😮 That only leaves 46 Vac on the other line! THAT'S a serious imbalance. Looking back on it now I'm amazed that only the odd light burned out. Today's CHEAP electronic crap wouldn't stand up to that kind of abuse. I went to the basement and checked the breaker panel for heat and it was so HOT I couldn't touch it for more than a fraction of a second. I took the cover off and found the main neutral connection was loose. I tightened it up and never had that problem again. That burned into my mind just how dangerous a loose neutral or disconnecting a neutral that is BEING USED can be!

Nice job!

This happen to me 4 years ago. Took 4 calls to the electric company. I told them I was seeing 136 volts on one side and 108 volts on the other. They changed the meter and never tightened the screw on the neutral. Melted the screw and the aluminum wire. Amazing people like I had come out never checked it.

Yes, go for a microwave NOT a dryer, oven or stove element as they are all 240V load or "balanced loads. As Bob said "Unbalanced or phase to neutral loads." Ungrounded to grounded conductor. Ground current can also go up. Fun fact - when the neutral is breaks on Triplex, the #6 grounding wire tries to carry the load and will burn vinyl siding.

I agree with thephantom1492. Test each hot leg to ground. If you get an imbalance put jumpers in the channel and read across the neutral connection in the channel. If that connection is bad you will read the imbalance voltage. If it reads zero do the same thing at the weatherhead. If it reads zero there now you have to go to the pole. Where ever you read voltage across the neutral connection that is your bad connection. If there is an inline splice half way between the house and the pole which is not a normal electrical splice that also could be where the problem is. Most of the time this kind of problem will cause dim and bright lights. I've seen it high enough on the high side to do damage to electronic equipment.

This was an excellent video That could even speak to balancing Your Box at a house when doing a remodel...Love these technical Vids. On the flip Side I've asked before Can u do More on 34kv, Identifying POTS , Insulators are typically not a good way of knowing anymore based on size because they over insulate regardless of voltage. . Also Curious If you Have anything On trailering Poles out to jobsites and what types Of trailers used. We Do a lot Of Projects for Excelon South Of You and power upgrades asking us For Class 2 55 and 60 Poles. As You know I'm telecom and we work with one of there local companies in and outside of Philadelphia. Starting to question The trailers we are allowed to use with some 10 plus feet of pole hanging off the end of our 45 foot trailer. Couldn't find anything IN Our Department of transportation saying it shouldn't be allowed to have that much hanging Off the Back But yeah Your standards north of the border would be a great Video.. Its getting sketchy... Any questions please ask

Good info thanks

I’m in school to become a maintenance technician and one of our classes was a troubleshooting class and finding a neutral issue was the hardest part

Fascinating

I wonder if it would be possible to have a test apparatus that plugs into the meter socket that allows applying a loads without energizing the customer equipment, with voltage and current measurement points. Take the guesswork out and prevent a bad case like this one from doing more damage.

We experienced a lost neutral at my family's home a year or two ago. We were having weird problems with lights getting brighter/dimmer as other loads (AC, microwave, dishwasher, etc) came on and off. After checking with a multimeter and getting 150+ volts (IIRC), we shut off the main breaker for the evening and called our power company in the morning. The lineman who came out to check the issue actually had a box that slotted into the meter socket and, based on my best guess, contained a pair of loads on switches to test the legs. Turned out the neutral had broken off of the transformer. But a dedicated leg testing tool definitely seems like a safer option then asking someone to turn on high power appliances in their home.

I received a call out to a residence that recently had a new service pole and pole light from the supplier…flickering occasionally…went thru the typical checks, loose something here or there, finally got suspicious and went to the service disconnect…incoming lines were 150 something and 80 something as I recall…wowzer! quick call to the service center and had them out shortly after…the pole well off the road had the transformer mounted and it was their baby from there…they had to cut trees, all sorts of bs to get to it….they never indicated what exactly was the culprit..I suspect it was from the transformer to the triplex..as they needed to head back for wire…

as a electrical business owner in nova scotia ill look out for this issue in the future

Great video Aaron! By the way why Bobs Decline?Just curious…

I hate neutral problems... Thanks for the troubleshooting vid... I check up to the meter and then call the line guys...learn something on all your videos... Thanks...

Can you guys imagine bed neutral here in EU? We have 400v three phase service and 230v across phase and neutral. If you get a floating neutral, there are wild swings in voltage drops/jumps. You might have 50v on one side and 330v on the other leg, depends of imbalance. Stay safe, greetings!

If you lose your neutral all together then things go from bad to worse real quick. I've seen around 220Vac on one leg before which means everything not being protected behind a surge protector gets destroyed instantly 🤢 It all depends on how the 120Vac legs are loaded because with the Neutral (transformer center-tap) disconnected the circuit becomes a voltage-divider hence the voltage across each leg is based solely on the resistive loads. Unless the loads on each 120Vac legs are balance then you'll have more voltage on one 120Vac leg compared to the other. I've seen linemen remove the service meter and plug a device into the meter base to simulate an unbalanced load to find the problem so there is no need to bother the customer with turning on appliances. Just wondering if it was re-crimped with "anti-oxidant joint compound" to prevent the cable from oxidizing again due to heat which is why that connection was failing to begin with. It's not rocket science 😊 Checkout "Open Neutral" on Dave Gordon's channel which perfectly illustrates this problem 😉 By the way, this is exactly how to check for bad wire or connections on a 12-24Vdc system using the "LoadPro" probe. Open voltage won't show the problem until you put a load across it then the voltage drop becomes obvious 🤠

This is exactly what happened to my house a few years ago. The lineman had me put a bowl of water in my microwave while he took readings. He re terminated the neutral connection at the transformer. No problems after that. It had been like that for a while. The spikes killed one of my UPS's and I had scorch marks on my light switches.