i am a master electrician and hvac tech over 30 years .I am disabled now .Everything you said is correct .the first thing l was taught about electricity is it all ways looking for the ground and you don`t want to be the best way to it! all ways turn the load off before turning on power!Because a loose connection under a load is the same a welder. it heats up and makes a bigger gap and bigger arc every time load comes on! and a breacker matches the size wire to protect the wire from heating up and burning!The nuetral is the designated path to ground and it just as hot as the power wire under a load!
This is good stuff, you don't have to be in the electrical trade to need to learn the stuff I understand it, which is what I appreciate about this channel. People have trained in HVAC, I have sent them your way to do some homework. Videos like this being a perfect example, because I tell everyone, if you're not putting in time off the clock as well you're never going to succeed or learn what you need to learn or need to know
@@josemartinez-jt6tw Buy some textbooks. See if your job will cover a few semesters of trade schools. I know a lot of employers do. That's how I got through trade school and got my certs. I wouldnt be where I am today if I didnt put my head to the ground and go for it.
YUP ppl who like this, their mind will absorb any info when they work on projects, sort of like seeing twine broken on motor windings, it is quite likely there will be a discoloration of the windings. even from years past seeing discolored coils in a motor or gen you'll remember the twine was most likely broken leading to the fact the coil overheated and a good chance there will be a shock hazard.
I have had to learn to put things together and diy a lot of things I had an idea on but never really attempted. But I’ve been trying to fix a freaking power wheel for 2 years and electricity and how to really use the multimeter just collapse my ability to think it thru! Maybe I just need to try the thingy that beeps when there’s loss of a circuit connection thru wires. “Volt detector” because I’m getting nowhere with the multi idk what to stick the neg probe to for the different places to check. I always thought it was just stick to beg red to pos but something’s you just need beg prove to ground well idk what’ all is safe to just stick it to.
We had a job subbing for a company that had a contract to move all the service meters from the panels on the sides of mobile homes to pedestals in the front corner of the houses. They ran all the new supply lines under the houses to the main panels. Our job was to solve all the ground to neutral faults in the whole park. As well as replace some very old or under rated panels and any other problems. I did all the troubleshooting with my apprentice helping. We had to open and disconnect a lot of wire nuts. First thing we always did was pull the electric dryer cord. A lot of those are neutral bonded to ground. Keep up the great videos. Still learning and finding better ways to explain things to apprentices and customers. Even though I have my own company now.
I'm a retired sparky with over 50 years in this great trade. Several times I have came out and found that a circuit breaker trips as soon as you turn it on. Unplugged everything & turned every switch on that circuit off and problem did not go away. Could not pick up and grounds on either of my VOM'S. Used my expensive Fluke combination VOM/ Megger. Did not pick up a ground at 50 volts but got a low resistance reading using 100 volts. One of these was caused by water that halve filled an outdoor receptacle box. Another time old rubber insulated wire had broken pieces of insulation allowing two wires maybe seperste by a hair. If I had 10 devices on a circuit would try to guess middle point and disconnect wired then flip the breaker.
If your having trouble finding if you have a ground fault or short circuit, and tried removing appliances, turning wall switches off with no success, then you know the problem is within the building. Because grounds and neutrals ultimately end up at the same place in the main panel, what you might consider doing is removing the neutral of the problem circuit from it's bus bar, then check if you have continuity between the hot coming off the breaker and the neutral. If you don't, but you have continuity between the hot and ground bus, you narrowed it down to a ground fault. In either case, ask yourself, what circumstances changed? Ex. an electric heater was being used for an extended period, and you smell burned plastic near a receptacle, see wisps of smoke, and now the breaker won't hold. Perhaps you heard a pop or crackle, or seen a flash, before the breaker tripped. You narrowed it down to a ground fault in the building wiring. Upon pulling devices upstream of the space heater location, you find a wirenut had burned off the hot wire and is touching the metal box. Not all troubleshooting is going to be so simple and logical, but you get the idea.
This should be obvious, but never test continuity on a live circuit, e.g., using the meter in continuity mode across hot and neutral, hot and ground, or hot to hot (for 220V). A Harbor Freight quality meter will be destroyed, a good meter will blow the fuse. While electricians don't typically use this, but there's a device called a Time Domain Reflectometer. It fires pulses down the line, and measures the return times. It can find shorts, changes in resistance, and open circuits. You can also measure the length of the wire if you know it's velocity factor. They're not crazy expensive, but they're not cheap either.
An excellent explanation. I would have only added the step of unplugging/disconnecting the load from supply wiring to isolate and narrow down possible causes.
Needed this today. Came across someone’s shoddy work and just immediately stressed out when I opened the j-boxes. Hopefully when I go back on Monday I can solve my problems.
That’s a great explanation of short vs ground fault and how to tell immediately. Older irrigation systems have convoluted messes of common wires with short hot wires. Ran into this problem today. Solenoid tester says it’s a short. Oddly enough I didnt check continuity but waiting on the area to be dug. Hand dug found the cables and there in a pool of water next to a 6” water pipe.
"Finding the knowns" … yeah, that's an amazing troubleshooting step - and applies to all kinds of stuff including outside electrical. I can't tell you how many times someone asks for help only to find out they skipped all the easy stuff to check, didn't "look for the knowns" and is struggling off in some completely unrelated area because of it. I always step ALL the way. back, start from the beginning/scratch, and yeah, go thru all the knowns and go from there.
@@desertodavid it's talked about in the vid. But no, basically starting with the basics, starting with the baseline. You need to start an investigation by starting with the basics, and finding out the most basic parts of the situation. It can be easy to be carried away jumping into a situation going off of what other people have said, only to find out they missed something SUPER easy / simple because they skipped the basics and went right into more complex situations. (or you yourself doing the same thing. "I am so smart, it MUST be this instead of like… checking breakers, checking how the wires are connected, tracing them out, etc. A bad assumption can send you down a totally wrong path. You may end up with the final solution anyways - but all that could be skipped if the basics/knowns of the setup are determined first.
I love your channel, you are awesome! Very helpful and you explain in a way that a less experienced person like myself can understand. Thank you so much for being here. Kind Regards. Philli.
Man the way you explain it makes me understand it much better, thank you. That mentor you had is the man. Knowns is what will help you pin point the issue.
Prior to continuity check, It seems a very important step is to disconnect the device from the supply neutral (and hots) otherwise the bonding at service panel will not allow you to differentiate between neutral and ground.
Beautifully simple explanations. I'm only up to 6:53 but as a software engineer my immediate approach is to remove things (obviously easier in software). So my first thought was "Test the circuit with something other than the dryer". I'm guessing this is really not always an option. I mean it's not like you can swap the dryer for a lamp...nonetheless sharing my thoughts, looking forwards to the res of the explanation, already subscribed
Fantastic job on explaining how to troubleshoot a circuit issue! Many times the first thing people think is that it must be a wiring problem without considering the possibility that it could be something running off the circuit.
We would get sent out to work on a customer's turbine with a "known" issue. That is, until we got on site and found that the customer's "known" issue didn't make sense. I finally figured out that the best thing to do was to start shooting the breeze with one of the operators and find out what they were trying to do when the "known" issue popped up. It usually had nothing to do with what the office people said it was. It usually also pointed out that they did something stupid or that something else on site caused the issue to begin with and the turbine was collateral damage. Really cut down on the troubleshooting. Know your knowns. I like that.
This is SO true. We tell all out clients, very politely, to just describe the problem without any speculation. Of course, if someone spilled their coffee on the control panel, I’d like to know that too 😏😏.
Thanks for the great video!! Definitely helpful in understanding it. I do use continuity alot for troubleshooting. Have an outside project (still not finished) alot receptacles In the yard where over time got covered over with dirt and multiple shorts in the circuit, I take sections at a time and test continuity and finally figure out where and which wire. It's been a nightmare job and still a few left to do.
Hey man, thank you so much for all of the valuable info on your channel. I’m a coffee tech (espresso machines, commercial brewers, etc) so we basically need to be baby plumbers, baby mechanics, and baby electricians. The electrical side of things is always where I felt the least comfortable, but your videos really helped me step up and feel like I have a handle on what previously felt like black magic.
If there's continuity between the black and the neutral (a short) there's also going to be continuity between the black and the ground, because there's continuity between the neutral and the ground (they're bonded at the panel), no?
Dustin, you're awesome! Experience comes from years on job. We always learn everyday. No way we can know it all. I was taught at early age, "we stop learning, when we allow ourselves to not want to take anymore in". Best tip to apprentice is, do not say ya know, if ya don't. Always ask questions, its better to ask the 'why' , then to just keep doing, cuz you're told so. That will show interest in trade and jman will appreciate it ( well, most would, lol). Cheers from Pennsylvania!
Dustin, could you please do a video with tips and tricks to troubleshooting with both a multimeter and a clamp meter? I’m an industrial electrician that’s been with my company for a year, and I’d like to get into service calls and learning how to use my meters to help with troubleshooting. Love your videos, and I would appreciate it a lot. Thanks in advance if you do this.
I do industrial as well 3y in....I believe it's a fluke 375 that measures in rush.....I'm wondering if I clamped the neutral close breaker and got a inrush value turned around and did the same for ground how they would compare...the expectation is to try and catch the one drawing excessive current to determine short circuit or ground fault...
Be prepared to be humbled. Service work and troubleshooting is a whole different animal than commercial/industrial new construction. But it will be good experience for you and I highly recommend every apprentice down both new construction and service work. I'm a journeyman and still struggle with troubleshooting at times and using my meter. When you install for awhile and do nothing but bend pipe you get a little rusty when you actually have to think like an electrician. Hell just last week I had to look up how to calculate a lighting load using ohms law. I had brain dumped all that and haven't done a calculation in God knows how long.
Thanks - lots of really great info. One suggestion - deliver the info in several passes, making the first pass really short with just the basic central ideas, and then proceed to a couple more levels of telling the story with increasing detail - increasing the amount of special cases and circumstances that could arise. I'm thinking of how newspaper stories are written in "pyramid style."
As a homeowner and DIY electrician, thank you sooooo much for the education you provide. It has made me better and allowed me to make repairs that are safe.
There may not be "continuity" as defined by your DMM when a device is turned on. This is because the continuity feature of DMMs beeps below 1-2 ohms. But the actual load may be hundreds to hundreds of thousands of ohms. That said... __NEVER__ use the ohms/continuity reading of a DMM on a live circuit. You'll either blow a fuse in your DMM, damage your DMM, or explode your DMM (depending on the voltage across your DMM leads when you take the reading and the safety features inside your DMM).
Yes, you are correct regarding continuity. I have seen electrician's test with a meter, its open circuit. No, your meter has a maximum of 2k, anything over this will show open circuit. You need to read the meter manual and understand its limits.
Hey when I was in college studying networking, we had a tool called a Fox and Hound. It sent a signal Through the Wire, and you could pick it up with a handheld device. Is that possible for electrical wires? Like if the wire did find a shortcut, could it be used to find where the shortcut is?
good videos for education. I prefer hands on in a residential real multi-net circuit. my problem in the house is the previous owner had overlapped two circuits + a faulty circuit in a failed GFCI that was passing hot to neutral, go swap those old GFCIs. last if the problem is not going away after replacing GFCIs don't waste your time digging in each section of the house. unplug appliance this to include lightings, treadmills, etc. then go to the main circuit switch with non-touch or non-contact pen with the power on. (you have to be confident tech to do this don't shock yourself!). touch each individual ground and neutral with the pen and document it. all of them suppose to return 0 or no voltage because I expect that you have switched all the circuit to off position. main grid power must remain on during this operation to see which local circuit is passing a hot to a neutral (hot to neutral is generally caused by bad wiring, or failed GFCI that passed hot to neutral), if ground is getting hot for a given circuit or net within the house that one is passed to every single ground in the house, so start with the very main circuit board or fuse box in your house. saves time. you must have these tools to perform this: non-touch non-contact pen, and a gfci fault detection tool, extra brand new certified GFCI receptacles, and a clamp meter is extra but it works great and you will end needing this if you constantly testing current and voltage running through the wires.
I know this isn't the subject bit I have a question. When installing a sub panel. Why do you need the bonding screw if the ground wire from the subpanel is connected to the neutral bus bar in the service panel to carry the fault current back to the transformer. Or is there a specific spot for the ground wire from the subpanel
Dustin. Very helpful. Question: It is necessary to de-energize a circuit before you test for continuity, yes? Were you assuming that with a tripped breaker, the circuit is by definition de-energized?
Good way to destroy your meter when checking for continuity if you did NOT DE-ENERGIZE your circuit! Continuity testing or resistance, (same circuit within the meter) relies on its own internal power.
True, sort of. You can have a ground fault with as little as a few milliamps of current. Often from a small cut or break in the insulation and often intermittent. That's why it's so important to megger new installations. Especially if you're using conduit.
Make sure the power is off. Disconnect the wiring to speed things up. Remember you will a always read continuity or "ohms" over a coil such as a heating element but you should more resistance over a coil then a derect short.
99% of the time it's not the wiring, it's the equipment connected. Disconnect the equipment and check if the breaker will reset. Depending on the fault a multimeter may not show the fault and an insulation resistance tester (Megger, trade name) may be required.
Hoping for info regarding testing continuity from an alternator. If I test across positive terminal on alternator to positive battery terminal I get a steady tone (beeeeeeeeep) and then when I test from alternator POS to ground I get a consistent broken tone (beep, beep, beep...). I ensured that both leads are making good contact at all times. Any idea what is happening with the broken beep? Thanks for any help.
Thanks for the video! I'm studying for my aptitude test to join IBEW. I know this isn't going to be on the test but its helpful to know for the interview and boot camp. Anything I can do now to get a leg up is helpful.
If you do the breaker thing just make sure the circuit is turnded off if doing continuity. Usally when i try to diagnose somehting I start as close to the source as i can and or the simplist to get to. I hade a table was that was acting odd for a bit then just stopped turning on. I tried a few different outlets played with the internal breaker, switch. I then unplugged turned on checked continuity to between the hot and neutral was open. So then tore into the switch, breaker, checked the cord they were all fine. That pretty much left the motor, checked that open circuit, checked from each line to each brush one was open so figured either a winding failed, thermal cutout, or maybe a bad connection. Ended up tore apart was a loose spade terminal on the brush holder fixed good as new. I'd do similar for something like this remove anything that would show like a load then start from source and work back until you find somehting that seems off.
Hi there. When installing a neutral wire in an old house. Is it ok to install a single wire or do you have to grab the entire shielding of the romex and cap the black wiree?
Best practice would be to always cap off wires, even if they aren't connected to anything. They can become energized due capacitive or inductive coupling, or even touch something live.
Is there such a thing as a ground fault that doesn’t trip the breaker on my main panel? Have a sump pump that trips the GFCI at the outlet, even when the pit is dry. but when I temporarily plugged it into a standard outlet it worked fine, doesn’t trip anything at the panel. Replaced the gfci with a new one and it still trips when the pump is plugged in.
Good stuff Dustin, would love to see some more 3 phase 480V troubleshooting videos as an industrial electrician I would love to hear your take ! Keep pumping out this great content love it
Ok I see what you did between hot and neutral. Can I test each conductor to ground? Like test for continuity to see if 1 of the wires is going to ground?
Hi! I have a Hyundai Tucson 06 with a irbag light on,scanner states B1326 code (FIS) Front impact sensor short to ground Drivers side. How would you trubleshoot this? Thanx in advance //Fredde
Great video! Wish I saw this last year, had a similar issue and did all kinds of troubleshooting to figure out it was a simple fix in the junction box, felt dumb. BUT hey, I have a random question, as a DIY homeowner, I have a couple spots I need to run new Romex to where the existing is 12/2 and I need 12/3. Talking to people I work with they all make it sound so simple, attach the new to the old and pull through DONE. Wrong, because from what I know and, in my situation, the installers staple it to studs in the wall. So how does a professional replace Romex in a finished wall? or do you cut open the wall, patch it up, and paint when done? Trying to avoid that, but it might be my last option. Thanks, appreciate the easy-to-understand info.
Dustin, what are the steps to find a partial short in an a/c circuit? I have a multiple outlet circuit along with a garage opener. The garage opener motor burnt up and is disconnected. The circuit now has a low voltage of 46 volts. Gary
DUSTIN, A Ground Fault is considered the Hot wire is directly connected to the Green wire Ground? a Short circuit is considered if a piece of the equipment's internal wiring or internal load is shorted from hot to neutral or the load is shorted from hot to chassis? How I would troubleshoot a ground fault or short circuit is shut off the breakers then disconnect the Hot, Neutral and Ground wires to the load/equipment, then use my DVM meter to test if the wires are shorted or if the equipment/load is shorted. This method is better because you can diagnose if the load/equipment has an internal short circuit or an internal wiring ground fault. If you don't disconnect the H,N,G wires and multiple pieces of equipment/loads are on the "Same Branch/Same Breaker connected "in parallel" you will be guessing, because a short circuit and ground fault will measure both the same in "milliohms". What is even worse to troubleshoot when you have a short circuit that crossed over in a wiring harnesses in the wall or internal inside a piece of equipment/load to another wiring harness that is on another breaker which you will have "leakage current" or Ghost measurements". This would be a good video lesson about "ghost measurements" and leakage currents.
I buy cars from auction and my wife’s 2018 navigator shows a short to ground on the scanner. If I change the headlamp module and reset the codes, everything works but eventually it stops working then the other turn signal stopped working and the running lights on both. Trying to figure it out.
Hi there; question for you. I moved in into my home a year ago, the house is only 8 years old,and when changing some outlets in a bedroom to replace them with usb built-in I came across one outlet with the ground looped on the neutral side. The wiring is the original from when the house was built 8 years ago. If I undo the ground loop and turn the breaker on , it tripped (nothing connected to any of the outlets) I pulled out all of the outlets and switches to see if something was amiss. I turn the breaker back on without the loop and it didn’t trip but the connection that continues from this outlet (master bathroom) stopped working. Connecting the ground loop back to the neutral as I found it, resume power to the master bathroom I know without seeing it is hard, but do you have an opinion as to what’s going on?
One important fact to be noted is that a ground fault occurs when you have current flowing between neutral and earth ground. Normally there should be no current flowing between neutral and ground. A short circuit however is when you have diverted the current that would have normally flowed to a load through another path that is of much lower impedance. The short circuit could be between line and neutral or line to ground.
Great video! I know this is 1 year late, but I'm an apprentice, started doing sequence start with 3 phase motors, using 2 motors, the 2nd motor can only start once the 1st motor is running, however, when I attempt to start the 2nd motor, the MCB trips, not the overload, but the MCB (15amp mcb). I can't find the fault, could it be that the motors I'm using or a wiring fault. Can anyone please assist with this matter 🙏
So, you connect a multimeter, measuring continuity between live and neutral hopping for continuity. What if there is no short circuit and you apply 117V to the multimeter leads? If the short is far from the measuring point the continuity may not work... I probably didn't understand
something to also keep in mind. Ground faults are not only created by hot conductor(s) touching metallic frames or equipment grounds. I do a lot of outdoor lighting troubleshooting and can’t tell you how many times tripped GFCIs are caused by junction boxes located in the soil that have moisture contamination. Enough current is able to find its way to earth ground that it trips.
I use a light socket. Black from pigtail goes on breaker and neutral goes to the load. Short or ground fault circuits will cause light from bulb. When fault is cleared light goes off
So can you do a short video on the square d qo120PAF breakers and their service light codes? Service light flashes when I turn on breaker but no tripping occurs when we use all the outlets/lights - everything works fine but likely isn't as the light is flashing. Called Schneider support and they were no help
I have to ask if you have to tighten up the bolts that's coming in from the main pole to my box at the top can you or do you have a video on how to do that safely with out getting electrocuted???? Safety
So if the appliance is plugged in, but switched off, we should have continuity up to the point in the circuit where that on/off switch is, right? Like taking that simplified drawing of the washing machine, the red and black will have continuity until well inside the appliance, despite the appliance being switched off. Or not?
Still not subscribed. But, this is me commenting on yet another video. Good job on this explanation. You've broken down Root Cause Analysis into a very basic structure. 👍
I had the opportunity of being present when a 480v/1200a breaker was constantly tripping and it was a sight and sound to experience. It was an ice maker for a food processing plant, and the reason it kept tripping was too much in-rush current when the control system fired up the compressor(s) soft starts. I just needed to increase the breaker in-rush settings, so I learned some troubleshooting techniques that day.
Thank you for that, I forget about continuity. I have a old house with an old water heater and the breaker keeps getting tripped periodically. I have a home warranty that came with house and so I called and they sent guy out. Ended up changing 1 element but now 2 months later same issue. I'm not going to pay again to send same guys out so I'm going to see if I can figure out which one is broke or if another problem, thank you.
This is a perfectly valid troubleshooting technique to narrow the fault down to a specific appliance or identify if the building wiring is the fault if the fault still shows with everything unplugged/disconnected.
I got a question, how do you find a good ground when testing a panel or machine. Like which place is best to put the black lead of the tester if there is no obvious ground screw? I was testing a micro switch and I failed the exam bec. I can't find a good ground in the machine. Bec. normally you put the black lead on the ground and the red on the circuit you gonna test to find the voltage.
Thanks for explaining the ground vs ground short. I'm an appliance repair guy and I always start from the wall outlet then work my way inside then go to the load and trace the circuit.
I know what you mean about checking 'the knowns ', I'm a heating engineer, work on boilers and stuff. When I get a call out, cos someone's heating is not working. The first thing I do is find out if their gas meter is topped up, (a lot pay as you go customers in London), so yes you right, check the knowns ; simple things like checking to see if there is gas flowing on cooking hubs in the kitchen. You will be surprised how many times that's the case: no gas.😊, Another thing, always let the customer tell you what happened. They may already have diagnosed the problem for you.
You mentioned that you should never have continuity between a hot and a ground..I agree with that on an appliance, however, it can tone out with lightbulbs sometimes. Can you touch on that and explain it?
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i am a master electrician and hvac tech over 30 years .I am disabled now .Everything you said is correct .the first thing l was taught about electricity is it all ways looking for the ground and you don`t want to be the best way to it! all ways turn the load off before turning on power!Because a loose connection under a load is the same a welder. it heats up and makes a bigger gap and bigger arc every time load comes on! and a breacker matches the size wire to protect the wire from heating up and burning!The nuetral is the designated path to ground and it just as hot as the power wire under a load!
I’m glad you made this video. You’d be surprised how many electricians don’t realize the difference between ground faults and short circuits.
I'm a green maintenance tech and this video helped me out a lot.
This is good stuff, you don't have to be in the electrical trade to need to learn the stuff I understand it, which is what I appreciate about this channel. People have trained in HVAC, I have sent them your way to do some homework. Videos like this being a perfect example, because I tell everyone, if you're not putting in time off the clock as well you're never going to succeed or learn what you need to learn or need to know
Im in hvac and struggle electrical n using my meter
@@josemartinez-jt6tw Buy some textbooks.
See if your job will cover a few semesters of trade schools. I know a lot of employers do. That's how I got through trade school and got my certs. I wouldnt be where I am today if I didnt put my head to the ground and go for it.
YUP ppl who like this, their mind will absorb any info when they work on projects,
sort of like seeing twine broken on motor windings, it is quite likely there will be
a discoloration of the windings. even from years past seeing discolored coils in a
motor or gen you'll remember the twine was most likely broken leading to the
fact the coil overheated and a good chance there will be a shock hazard.
I have had to learn to put things together and diy a lot of things I had an idea on but never really attempted. But I’ve been trying to fix a freaking power wheel for 2 years and electricity and how to really use the multimeter just collapse my ability to think it thru! Maybe I just need to try the thingy that beeps when there’s loss of a circuit connection thru wires. “Volt detector” because I’m getting nowhere with the multi idk what to stick the neg probe to for the different places to check. I always thought it was just stick to beg red to pos but something’s you just need beg prove to ground well idk what’ all is safe to just stick it to.
We had a job subbing for a company that had a contract to move all the service meters from the panels on the sides of mobile homes to pedestals in the front corner of the houses. They ran all the new supply lines under the houses to the main panels. Our job was to solve all the ground to neutral faults in the whole park. As well as replace some very old or under rated panels and any other problems. I did all the troubleshooting with my apprentice helping. We had to open and disconnect a lot of wire nuts. First thing we always did was pull the electric dryer cord. A lot of those are neutral bonded to ground. Keep up the great videos. Still learning and finding better ways to explain things to apprentices and customers. Even though I have my own company now.
Remember when testing resistance or continuity remove power or turn off power. Thanks for the info, helpful.
I'm a retired sparky with over 50 years in this great trade. Several times I have came out and found that a circuit breaker trips as soon as you turn it on. Unplugged everything & turned every switch on that circuit off and problem did not go away. Could not pick up and grounds on either of my VOM'S. Used my expensive Fluke combination VOM/ Megger. Did not pick up a ground at 50 volts but got a low resistance reading using 100 volts. One of these was caused by water that halve filled an outdoor receptacle box. Another time old rubber insulated wire had broken pieces of insulation allowing two wires maybe seperste by a hair. If I had 10 devices on a circuit would try to guess middle point and disconnect wired then flip the breaker.
If your having trouble finding if you have a ground fault or short circuit, and tried removing appliances, turning wall switches off with no success, then you know the problem is within the building. Because grounds and neutrals ultimately end up at the same place in the main panel, what you might consider doing is removing the neutral of the problem circuit from it's bus bar, then check if you have continuity between the hot coming off the breaker and the neutral. If you don't, but you have continuity between the hot and ground bus, you narrowed it down to a ground fault. In either case, ask yourself, what circumstances changed? Ex. an electric heater was being used for an extended period, and you smell burned plastic near a receptacle, see wisps of smoke, and now the breaker won't hold. Perhaps you heard a pop or crackle, or seen a flash, before the breaker tripped. You narrowed it down to a ground fault in the building wiring. Upon pulling devices upstream of the space heater location, you find a wirenut had burned off the hot wire and is touching the metal box. Not all troubleshooting is going to be so simple and logical, but you get the idea.
These kinds of comments you find in youtube are solid gold. Thanks professor!
This should be obvious, but never test continuity on a live circuit, e.g., using the meter in continuity mode across hot and neutral, hot and ground, or hot to hot (for 220V). A Harbor Freight quality meter will be destroyed, a good meter will blow the fuse. While electricians don't typically use this, but there's a device called a Time Domain Reflectometer. It fires pulses down the line, and measures the return times. It can find shorts, changes in resistance, and open circuits. You can also measure the length of the wire if you know it's velocity factor. They're not crazy expensive, but they're not cheap either.
An excellent explanation. I would have only added the step of unplugging/disconnecting the load from supply wiring to isolate and narrow down possible causes.
Needed this today. Came across someone’s shoddy work and just immediately stressed out when I opened the j-boxes. Hopefully when I go back on Monday I can solve my problems.
That’s a great explanation of short vs ground fault and how to tell immediately.
Older irrigation systems have convoluted messes of common wires with short hot wires.
Ran into this problem today. Solenoid tester says it’s a short. Oddly enough I didnt check continuity but waiting on the area to be dug. Hand dug found the cables and there in a pool of water next to a 6” water pipe.
"Finding the knowns" … yeah, that's an amazing troubleshooting step - and applies to all kinds of stuff including outside electrical. I can't tell you how many times someone asks for help only to find out they skipped all the easy stuff to check, didn't "look for the knowns" and is struggling off in some completely unrelated area because of it. I always step ALL the way. back, start from the beginning/scratch, and yeah, go thru all the knowns and go from there.
@Colinstu by "knowns" are you talking about "probable faults" in a circuit?
@@desertodavid it's talked about in the vid. But no, basically starting with the basics, starting with the baseline. You need to start an investigation by starting with the basics, and finding out the most basic parts of the situation.
It can be easy to be carried away jumping into a situation going off of what other people have said, only to find out they missed something SUPER easy / simple because they skipped the basics and went right into more complex situations. (or you yourself doing the same thing. "I am so smart, it MUST be this instead of like… checking breakers, checking how the wires are connected, tracing them out, etc. A bad assumption can send you down a totally wrong path.
You may end up with the final solution anyways - but all that could be skipped if the basics/knowns of the setup are determined first.
@@colinstu nevermind. Obviously you don't know what I mean by probable faults. I'm an experienced Electronics technician, so save your time.
@@desertodavid oh, PROBABLE, I read that as "ground" (as in ground faults). Yeah that's definitely all part of it.
I love your channel, you are awesome! Very helpful and you explain in a way that a less experienced person like myself can understand. Thank you so much for being here.
Kind Regards.
Philli.
Man the way you explain it makes me understand it much better, thank you. That mentor you had is the man. Knowns is what will help you pin point the issue.
Prior to continuity check, It seems a very important step is to disconnect the device from the supply neutral (and hots) otherwise the bonding at service panel will not allow you to differentiate between neutral and ground.
You'r Right .
My trade school just uses you videos to teach us ⚡️⚡️
This video helped me fix a lighting issue , thank you!
I'm in hvac but we do some of our own electrical. Making me a better tradesman. Thank you
Beautifully simple explanations. I'm only up to 6:53 but as a software engineer my immediate approach is to remove things (obviously easier in software). So my first thought was "Test the circuit with something other than the dryer". I'm guessing this is really not always an option. I mean it's not like you can swap the dryer for a lamp...nonetheless sharing my thoughts, looking forwards to the res of the explanation, already subscribed
Fantastic job on explaining how to troubleshoot a circuit issue! Many times the first thing people think is that it must be a wiring problem without considering the possibility that it could be something running off the circuit.
We would get sent out to work on a customer's turbine with a "known" issue. That is, until we got on site and found that the customer's "known" issue didn't make sense. I finally figured out that the best thing to do was to start shooting the breeze with one of the operators and find out what they were trying to do when the "known" issue popped up. It usually had nothing to do with what the office people said it was. It usually also pointed out that they did something stupid or that something else on site caused the issue to begin with and the turbine was collateral damage. Really cut down on the troubleshooting. Know your knowns. I like that.
This is SO true. We tell all out clients, very politely, to just describe the problem without any speculation. Of course, if someone spilled their coffee on the control panel, I’d like to know that too 😏😏.
This video is like the gold rush, because I'm finding lots of gold nuggets in here! Thanks for the great info Dustin!
Thanks for the great video!! Definitely helpful in understanding it. I do use continuity alot for troubleshooting. Have an outside project (still not finished) alot receptacles In the yard where over time got covered over with dirt and multiple shorts in the circuit, I take sections at a time and test continuity and finally figure out where and which wire. It's been a nightmare job and still a few left to do.
Hey man, thank you so much for all of the valuable info on your channel. I’m a coffee tech (espresso machines, commercial brewers, etc) so we basically need to be baby plumbers, baby mechanics, and baby electricians. The electrical side of things is always where I felt the least comfortable, but your videos really helped me step up and feel like I have a handle on what previously felt like black magic.
Incredibly good explanation and top notch presentation style. Thanks for doing this.
If there's continuity between the black and the neutral (a short) there's also going to be continuity between the black and the ground, because there's continuity between the neutral and the ground (they're bonded at the panel), no?
Very informative. He clearly knows his business. Excellent presentation.
Dustin, you're awesome!
Experience comes from years on job. We always learn everyday. No way we can know it all.
I was taught at early age, "we stop learning, when we allow ourselves to not want to take anymore in".
Best tip to apprentice is, do not say ya know, if ya don't. Always ask questions, its better to ask the 'why' , then to just keep doing, cuz you're told so.
That will show interest in trade and jman will appreciate it ( well, most would, lol).
Cheers from Pennsylvania!
Dustin, could you please do a video with tips and tricks to troubleshooting with both a multimeter and a clamp meter? I’m an industrial electrician that’s been with my company for a year, and I’d like to get into service calls and learning how to use my meters to help with troubleshooting. Love your videos, and I would appreciate it a lot. Thanks in advance if you do this.
Trouble shooting with a clamp meter? Are you talking about an amp probe?
I do industrial as well 3y in....I believe it's a fluke 375 that measures in rush.....I'm wondering if I clamped the neutral close breaker and got a inrush value turned around and did the same for ground how they would compare...the expectation is to try and catch the one drawing excessive current to determine short circuit or ground fault...
@@gp3646 amp clamp
Be prepared to be humbled. Service work and troubleshooting is a whole different animal than commercial/industrial new construction. But it will be good experience for you and I highly recommend every apprentice down both new construction and service work. I'm a journeyman and still struggle with troubleshooting at times and using my meter. When you install for awhile and do nothing but bend pipe you get a little rusty when you actually have to think like an electrician. Hell just last week I had to look up how to calculate a lighting load using ohms law. I had brain dumped all that and haven't done a calculation in God knows how long.
thank you for the explanation. The ways to explain this was some simple. 💯
I like when flames come out of the breaker when you reset it and your hand is on the breaker along with a nice pow.
Thank you for uploading this precious educational video on RUclips.😊😊😊
When checking continuity you have to turn off breaker right? So you dont damage your multimeter..?
Not sure why. I wire nothing. But, I love the understanding. Great job.
Great advice on gathering the "knoiwns" , in the process you will get to the problem.
Thanks for your teaching!❤❤❤
Keep doing videos like this,I really appreciate them
Thanks - lots of really great info. One suggestion - deliver the info in several passes, making the first pass really short with just the basic central ideas, and then proceed to a couple more levels of telling the story with increasing detail - increasing the amount of special cases and circumstances that could arise. I'm thinking of how newspaper stories are written in "pyramid style."
As a homeowner and DIY electrician, thank you sooooo much for the education you provide. It has made me better and allowed me to make repairs that are safe.
DIY electrician 😂😂
@@Dave0Star just for clarity, that was meant to be tongue in cheek 😉
You have to be the best instructor in the world, thanks for your video
There may not be "continuity" as defined by your DMM when a device is turned on. This is because the continuity feature of DMMs beeps below 1-2 ohms. But the actual load may be hundreds to hundreds of thousands of ohms. That said... __NEVER__ use the ohms/continuity reading of a DMM on a live circuit. You'll either blow a fuse in your DMM, damage your DMM, or explode your DMM (depending on the voltage across your DMM leads when you take the reading and the safety features inside your DMM).
Yes, you are correct regarding continuity. I have seen electrician's test with a meter, its open circuit. No, your meter has a maximum of 2k, anything over this will show open circuit. You need to read the meter manual and understand its limits.
On flukes the continuity setting is usually below 80 ohms
Thank you for all this information. I’ve learned a lot from your channel. Just curious, what is the multimeter that you use?
This was an excellent video with wisdom that applies to fields far outside of just electrical. Great troubleshooting advice for all troubleshooting.
Hey when I was in college studying networking, we had a tool called a Fox and Hound. It sent a signal Through the Wire, and you could pick it up with a handheld device. Is that possible for electrical wires? Like if the wire did find a shortcut, could it be used to find where the shortcut is?
good videos for education. I prefer hands on in a residential real multi-net circuit. my problem in the house is the previous owner had overlapped two circuits + a faulty circuit in a failed GFCI that was passing hot to neutral, go swap those old GFCIs. last if the problem is not going away after replacing GFCIs don't waste your time digging in each section of the house. unplug appliance this to include lightings, treadmills, etc. then go to the main circuit switch with non-touch or non-contact pen with the power on. (you have to be confident tech to do this don't shock yourself!). touch each individual ground and neutral with the pen and document it. all of them suppose to return 0 or no voltage because I expect that you have switched all the circuit to off position. main grid power must remain on during this operation to see which local circuit is passing a hot to a neutral (hot to neutral is generally caused by bad wiring, or failed GFCI that passed hot to neutral), if ground is getting hot for a given circuit or net within the house that one is passed to every single ground in the house, so start with the very main circuit board or fuse box in your house. saves time. you must have these tools to perform this: non-touch non-contact pen, and a gfci fault detection tool, extra brand new certified GFCI receptacles, and a clamp meter is extra but it works great and you will end needing this if you constantly testing current and voltage running through the wires.
I've always used the term ground fault to refer to an issue that happened on a switched return circuit.
Thanks for your time an videos iam sure I have a short going on with my dryer now got to find it but u save me with this video ty.
hi Dustin, can you make a video on the complete tutorial of the multimeter, as in how and when to use certain button.. on it ?
Thank You For the Knowledge. Your The man Seriously.
I know this isn't the subject bit I have a question. When installing a sub panel. Why do you need the bonding screw if the ground wire from the subpanel is connected to the neutral bus bar in the service panel to carry the fault current back to the transformer. Or is there a specific spot for the ground wire from the subpanel
Dustin. Very helpful. Question: It is necessary to de-energize a circuit before you test for continuity, yes? Were you assuming that with a tripped breaker, the circuit is by definition de-energized?
Good way to destroy your meter when checking for continuity if you did NOT DE-ENERGIZE your circuit! Continuity testing or resistance, (same circuit within the meter) relies on its own internal power.
This connected some really important dots for me. Thank you.
True, sort of. You can have a ground fault with as little as a few milliamps of current. Often from a small cut or break in the insulation and often intermittent. That's why it's so important to megger new installations. Especially if you're using conduit.
The best from the video was with the knows! It’s a life reminder.
Make sure the power is off. Disconnect the wiring to speed things up.
Remember you will a always read continuity or "ohms" over a coil such as a heating element but you should more resistance over a coil then a derect short.
99% of the time it's not the wiring, it's the equipment connected. Disconnect the equipment and check if the breaker will reset. Depending on the fault a multimeter may not show the fault and an insulation resistance tester (Megger, trade name) may be required.
90% of the time it’s a loose wire in the breaker
%100
Too long video
Hoping for info regarding testing continuity from an alternator. If I test across positive terminal on alternator to positive battery terminal I get a steady tone (beeeeeeeeep) and then when I test from alternator POS to ground I get a consistent broken tone (beep, beep, beep...). I ensured that both leads are making good contact at all times. Any idea what is happening with the broken beep? Thanks for any help.
Hi, how do you find a ground fault. I've checked all connections and replaced wire nuts and receptacle
Thanks for the video! I'm studying for my aptitude test to join IBEW. I know this isn't going to be on the test but its helpful to know for the interview and boot camp. Anything I can do now to get a leg up is helpful.
Good luck im in IBEW and it’s great
If you do the breaker thing just make sure the circuit is turnded off if doing continuity. Usally when i try to diagnose somehting I start as close to the source as i can and or the simplist to get to. I hade a table was that was acting odd for a bit then just stopped turning on. I tried a few different outlets played with the internal breaker, switch. I then unplugged turned on checked continuity to between the hot and neutral was open. So then tore into the switch, breaker, checked the cord they were all fine. That pretty much left the motor, checked that open circuit, checked from each line to each brush one was open so figured either a winding failed, thermal cutout, or maybe a bad connection. Ended up tore apart was a loose spade terminal on the brush holder fixed good as new.
I'd do similar for something like this remove anything that would show like a load then start from source and work back until you find somehting that seems off.
Hi there. When installing a neutral wire in an old house.
Is it ok to install a single wire or do you have to grab the entire shielding of the romex and cap the black wiree?
Best practice would be to always cap off wires, even if they aren't connected to anything. They can become energized due capacitive or inductive coupling, or even touch something live.
Is there such a thing as a ground fault that doesn’t trip the breaker on my main panel? Have a sump pump that trips the GFCI at the outlet, even when the pit is dry. but when I temporarily plugged it into a standard outlet it worked fine, doesn’t trip anything at the panel. Replaced the gfci with a new one and it still trips when the pump is plugged in.
Good stuff Dustin, would love to see some more 3 phase 480V troubleshooting videos as an industrial electrician I would love to hear your take ! Keep pumping out this great content love it
Ok I see what you did between hot and neutral. Can I test each conductor to ground? Like test for continuity to see if 1 of the wires is going to ground?
Hi!
I have a Hyundai Tucson 06 with a irbag light on,scanner states B1326 code (FIS) Front impact sensor short to ground Drivers side.
How would you trubleshoot this?
Thanx in advance
//Fredde
Great video! Wish I saw this last year, had a similar issue and did all kinds of troubleshooting to figure out it was a simple fix in the junction box, felt dumb.
BUT hey, I have a random question, as a DIY homeowner, I have a couple spots I need to run new Romex to where the existing is 12/2 and I need 12/3. Talking to people I work with they all make it sound so simple, attach the new to the old and pull through DONE. Wrong, because from what I know and, in my situation, the installers staple it to studs in the wall. So how does a professional replace Romex in a finished wall? or do you cut open the wall, patch it up, and paint when done? Trying to avoid that, but it might be my last option. Thanks, appreciate the easy-to-understand info.
Great teaching. Thanks for sharing this.
Dustin, what are the steps to find a partial short in an a/c circuit? I have a multiple outlet circuit along with a garage opener. The garage opener motor burnt up and is disconnected. The circuit now has a low voltage of 46 volts.
Gary
DUSTIN, A Ground Fault is considered the Hot wire is directly connected to the Green wire Ground? a Short circuit is considered if a piece of the equipment's internal wiring or internal load is shorted from hot to neutral or the load is shorted from hot to chassis? How I would troubleshoot a ground fault or short circuit is shut off the breakers then disconnect the Hot, Neutral and Ground wires to the load/equipment, then use my DVM meter to test if the wires are shorted or if the equipment/load is shorted. This method is better because you can diagnose if the load/equipment has an internal short circuit or an internal wiring ground fault. If you don't disconnect the H,N,G wires and multiple pieces of equipment/loads are on the "Same Branch/Same Breaker connected "in parallel" you will be guessing, because a short circuit and ground fault will measure both the same in "milliohms". What is even worse to troubleshoot when you have a short circuit that crossed over in a wiring harnesses in the wall or internal inside a piece of equipment/load to another wiring harness that is on another breaker which you will have "leakage current" or Ghost measurements". This would be a good video lesson about "ghost measurements" and leakage currents.
nice to hear someone talking that knows what they are saying.... lol.... thank you for what you do!
I buy cars from auction and my wife’s 2018 navigator shows a short to ground on the scanner. If I change the headlamp module and reset the codes, everything works but eventually it stops working then the other turn signal stopped working and the running lights on both. Trying to figure it out.
Do you check continuity with the power on?
Hi there; question for you. I moved in into my home a year ago, the house is only 8 years old,and when changing some outlets in a bedroom to replace them with usb built-in I came across one outlet with the ground looped on the neutral side. The wiring is the original from when the house was built 8 years ago. If I undo the ground loop and turn the breaker on , it tripped (nothing connected to any of the outlets)
I pulled out all of the outlets and switches to see if something was amiss. I turn the breaker back on without the loop and it didn’t trip but the connection that continues from this outlet (master bathroom) stopped working. Connecting the ground loop back to the neutral as I found it, resume power to the master bathroom
I know without seeing it is hard, but do you have an opinion as to what’s going on?
One important fact to be noted is that a ground fault occurs when you have current flowing between neutral and earth ground. Normally there should be no current flowing between neutral and ground. A short circuit however is when you have diverted the current that would have normally flowed to a load through another path that is of much lower impedance. The short circuit could be between line and neutral or line to ground.
Great video!
I know this is 1 year late, but I'm an apprentice, started doing sequence start with 3 phase motors, using 2 motors, the 2nd motor can only start once the 1st motor is running, however, when I attempt to start the 2nd motor, the MCB trips, not the overload, but the MCB (15amp mcb). I can't find the fault, could it be that the motors I'm using or a wiring fault. Can anyone please assist with this matter 🙏
Thank the gods for this man
So, you connect a multimeter, measuring continuity between live and neutral hopping for continuity. What if there is no short circuit and you apply 117V to the multimeter leads? If the short is far from the measuring point the continuity may not work... I probably didn't understand
These videos are fantastic
Keep up the great explanations!
something to also keep in mind. Ground faults are not only created by hot conductor(s) touching metallic frames or equipment grounds.
I do a lot of outdoor lighting troubleshooting and can’t tell you how many times tripped GFCIs are caused by junction boxes located in the soil that have moisture contamination. Enough current is able to find its way to earth ground that it trips.
I use a light socket. Black from pigtail goes on breaker and neutral goes to the load. Short or ground fault circuits will cause light from bulb. When fault is cleared light goes off
So can you do a short video on the square d qo120PAF breakers and their service light codes? Service light flashes when I turn on breaker but no tripping occurs when we use all the outlets/lights - everything works fine but likely isn't as the light is flashing. Called Schneider support and they were no help
I have to ask if you have to tighten up the bolts that's coming in from the main pole to my box at the top can you or do you have a video on how to do that safely with out getting electrocuted???? Safety
Wooooooo. using words properly . Im excited 😁
Dustin, Thank You ...Another great learning tip!!
So if the appliance is plugged in, but switched off, we should have continuity up to the point in the circuit where that on/off switch is, right? Like taking that simplified drawing of the washing machine, the red and black will have continuity until well inside the appliance, despite the appliance being switched off. Or not?
No not normally. Every device is different though so ymmv
I have 4 outlets that show ground fault and believe all are on the same breaker?
Still not subscribed. But, this is me commenting on yet another video. Good job on this explanation. You've broken down Root Cause Analysis into a very basic structure. 👍
I had the opportunity of being present when a 480v/1200a breaker was constantly tripping and it was a sight and sound to experience. It was an ice maker for a food processing plant, and the reason it kept tripping was too much in-rush current when the control system fired up the compressor(s) soft starts. I just needed to increase the breaker in-rush settings, so I learned some troubleshooting techniques that day.
Thank you for that, I forget about continuity. I have a old house with an old water heater and the breaker keeps getting tripped periodically. I have a home warranty that came with house and so I called and they sent guy out. Ended up changing 1 element but now 2 months later same issue. I'm not going to pay again to send same guys out so I'm going to see if I can figure out which one is broke or if another problem, thank you.
How do you go about asking questions
Could you unplug everything on that circuit breaker and plug them back in one at a time to identify which appliance is causing the fault?
This is a perfectly valid troubleshooting technique to narrow the fault down to a specific appliance or identify if the building wiring is the fault if the fault still shows with everything unplugged/disconnected.
I got a question, how do you find a good ground when testing a panel or machine. Like which place is best to put the black lead of the tester if there is no obvious ground screw? I was testing a micro switch and I failed the exam bec. I can't find a good ground in the machine. Bec. normally you put the black lead on the ground and the red on the circuit you gonna test to find the voltage.
how can i now if the connection of my house or a apc are faulty?
Great video. Very informative. Which model multi-meter is the one in the video? Looks like maybe the MM720
Thanks for explaining the ground vs ground short. I'm an appliance repair guy and I always start from the wall outlet then work my way inside then go to the load and trace the circuit.
I know what you mean about checking 'the knowns ', I'm a heating engineer, work on boilers and stuff. When I get a call out, cos someone's heating is not working. The first thing I do is find out if their gas meter is topped up, (a lot pay as you go customers in London), so yes you right, check the knowns ; simple things like checking to see if there is gas flowing on cooking hubs in the kitchen. You will be surprised how many times that's the case: no gas.😊, Another thing, always let the customer tell you what happened. They may already have diagnosed the problem for you.
Thank you, I was trying to understand this for some tìme.
Can a 120v heater use a 240v circuit? It makes it heat up much faster right? No?
You mentioned that you should never have continuity between a hot and a ground..I agree with that on an appliance, however, it can tone out with lightbulbs sometimes. Can you touch on that and explain it?