3 PHASE MOTOR TESTING - how too PROPERLY
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- เผยแพร่เมื่อ 24 พ.ย. 2024
- ALL MY MOTORS CONTENT IS IN THIS PLAYLIST !
• 3 PHASE MOTORS AND CON...
How to correctly identify the 4 main types of faults in a 3 phase motor with the correct testing procedure
the one stop guide to the testing process
further information on the insulation resistance tests in great detail can be found here
Insulation Resistance Testing Guide
www.chauvin-ar...
CA Webinar 8 Introduction to Insulation Resistance Testing
• CA Webinar 8 Introdu...
CA Webinar 9 Advanced Insulation Resistance Techniques
• CA Webinar 9 Advance...
Thanks for the video, helped knock off some of the cobwebs. Possibly a video looking at a bad motor in the future?
Cheers Jamie . Keep these videos coming. Really appreciate your time making them and sharing your experience and knowledge
Jamie I must say I always thought you were just a gobie sparky on podcast videos. After this video what can I say , your fantastic. Well good video. Respect.
I am a gobby sparky on podcasts your not wrong
thanks, didn't have a clue about giga ohms before now. using test results to see deterioration and anticipate a replacement motor was really interesting.
You know as little as me know
Top drawer instructional on motors pal. The g ohms chart at 20:45 makes things so much easier to understand. As others on here have mentioned. Fast becoming the go to channel on motor/process controls. Bangin wee video👌
Glad it helped
Great Video, There is alot of companies here in USA that do NOT go the extra mile and do this exact test, Lack of the info like u just showed leaves you hanging with what exactly failed or is failing. Excellent discriptive video.
Bro,I'd rather American engineers all day than a minute of a British engineer.
That includes all senior figures in my company who are supposed to be tech leaders but never have an academic concept behind anything they explain to you
They only want you to know what wire goes where or what colour wire goes where..
Just imagine he's explained Star n Delta wound motors by just let you craming how the linking plates are arranged ..What if those indicators are not there since someone perhaps removed them!!!!!
What about line voltage ,phase voltage ,line current ,phase current concepts behind delta or star wound motors
What about the concept of one then being a parallel circuit or series circuit!!!
If you know the nature of electrical faults being ground fault n such then you don't need this video
It's an insult to engineering
Love my electrical content, best I have seen in a long time.......👏
If you divide the volts by the resistance, that will give you the amps....Change the amps to KW and check against the motor plate... In this case 400 volts divided by 45 which is about 10amps .... then take 10amps * (400 volts divided by 1000watts) = 4 kw motor. Also, it is worth noting that one test that people don;t do is checking that you are not single phasing the motor. Make sure that you have all 3 phase's at the motor. It is common that a pole will fail across the contactor,. Test at the isolator incoming. Also, check that the motor is not seized.... Undo the fan shroud at the back of the motor and spin it by hand. Lastly, Check the motor plate, 3 phase motors have varied winding configurations like star delta, PWM, delta, delta..... etc
This has been absolutely brilliant mate! You break it down so well easy to follow! And as a Building services engineer dealing with motors it’s really helpful! Thank u as most of the time we are just asked to swap them out and the company pays thousands! Without even doing theses tests! 😅
Glad it helped mate
@@Actual_electrical_content At those potentials I don't think it's helpful for anyone other than a professional electrician perform fault diagnosis or pre-commissioning tests. Heard the saying... It's not on until it's tested?
Over 45years in the industrial electrical field, I've experienced many "Engineers" who use the "Truth by Authority" - "I'm an Engineer" - BS argument to assume repository of all knowledge of something they have never had direct experience in. i.e. full of shit.
If a Building Services Engineer (made up title?) tried to tell me my trade I'd tell em to complete the trade training (that as you know is a lot more complex than basic wire jerking, terminating and testing) and do years of practical experience before trying to lecture me.
eg. A "telecom engineer" claiming mechanical or electrical generation/distribution 'holder of all knowledge' status, in vastly different fields... You hear, "Oh, but he is an engineer.. he knows all".
Yeah... and remember, some salesmen call themselves 'sales engineers', only working in an office for years.
Sounds like you have little faith in the maintenance electricians that fault diagnose. Does this Co use qualified staff?
How is it, with such a job title, dealing with motors only on paper invoices, didn't you know this BASIC test procedure?
Seems like 'money' is prime concern there... a worry when safety, compliance, and industry best practice is of prime concern. I won't work in a place where money overrules either of those.
So, with this new basic 'knowledge' will you question the diagnostic skills of professional industrial electricians? If you tried that on with me I'd tell you to fukoff back to the office or waste more time and money proving my diagnosis wrong.
I used to think I was cool with my tera-ohms tester until someone pointed out I don’t need to measure tera-ohms, just look and see if the two cables are on opposite sides of the earth
P.S. another brilliant video. This three phase stuff is gold and hard to find on YT. More please.
Wait till you see how I discribe micro ohms in a future videos
Amazing mate thanks for the break down and the effort.
Faulty motor would be icing on the cake to see.
I’ll do an example when I find one
"..icing on the cake to see" ??
More like turd on a dinner plate to see.
Jamie,
I appreciate your time making these videos and sharing your experience, thank you.
My pleasure!
You're the Dave Savery of motors...brillant !
Never heard of her
Thanks mate , I love your lecture and the language used. you deserve a cool icy PINT if we ever meet.
cheers
Your wife buys me all the drinks mate but cheers
Really good Video thank you, its hard to find good videos about Motors and how to test them looking forward to more 🤙
More to come!
Absolute brilliant Jamie, good content and to the point. Most of all, some actual f@#ing practical testing that people can learn from. Well done mate! 👍👏👏
I'm glad I watched this video, I've watched a few of these videos on motors and leaned very little. this video showed exactly what I was looking for and explained it perfectly.
Glad it helped
Great video James about fault finding synchronization of ac induction motors 👍
Fantastic video mate , very well presented. With good clear easy to understand explanation. 👍
Cheers mate
Great video, thank you very much for taking the time and posting and putting in a few laughs. Videos like yours is what makes TH-cam great! Subscribed! I have a three phase motor which has the three wires coming directly out of it also a separate five pin connector. Thanks to your video I can test the motor itself. I'm not positive about the five pin connector if that will interfere with the test. The connector goes to a controller for throttle,forward and reverse.
If you contact me in instagram and send me a photos I’ll try to sort out and tell you you what’s going on
Thank you for making this video, I appreciate how in-depth you got. It was very helpful, dude!
Glad it was helpful! Come back for more
@@Actual_electrical_content Copy that! Subscribed.
Great video. You make learning my fun. Gonna look for a single ph video now!
God I wish I’d had this as a reference last month 😂😂 thrown on a job to diagnose a fault on a baby motor haven’t touched them in a long time…. This would have clarified a lot 😅 thanks
More conning
Interesting stuff Jamie. Enjoyed it. Would you use contact cleaner when you disconnect the cables and clean the terminals before reassembly? Look forward to the next episode.
Not really , they would have to be pretty dirty and that would no doubt show in the motor it’s self
Another great video Jamie, keep em coming
Hahaha how did you find this it’s unlisted
Great video Jamie
While on site during a Start Delta, Motor change we mixed up the incoming Yellow phases. Keep tripping overloads when switching to Delta. It was pulling serious current.
One phase was pulling the rotor in opposite direction
Complete nightmare it was.
Just took a photo of connections box, but realised later when looking harder at the photo wot the problem.
We draw them out now and label the shit out of it. 😂
Lesson hard learned.
There are 2 options on star delta starters , it works or it blows upb
mate this video sorted me out today fault finding a star heat pump motor cheers
Great video. Very informative. Thanks for taking the time to share your knowledge.
You deserve more subs, video has me cracking up
Funny , funny how …..
I enjoyed watching this Jamie, thanks and I didn't realise you had your own YT channel. I thought yopu just did the Sunday evening stuff. I look forward to watching the next installment and perousing your other stuff.
The DAR & PI input was good and for those who can't afford the Show-van Arnoo kit but still want something in their MFT for it, my Kewtech KT66DL does both with a decent explanation in the user manual about it, though not as good as yours -Obviously, but the good things with it is you can turn the lock feature on so no need to keep your finger on it.
probably the best 3 phase motor video ive ever watched , not as good as porn hub but still really good.
I can get my tits out of it helps
@@Actual_electrical_content obviously :-)
As a 40 plus years industrial maintenance electrician watched this out of curiosity I have a couple of comments. If you want to build the channel and come over as more professional drop the F words completely. Don’t get people tied up in Gig ohms they are totally pointless anything over 10 meg don’t worry in the real world. Forgot to say even after doing all this there can still be a problem, some motors just don’t play by the rules. Had one a while back where the customer had fitted his spare “rewound” motor to a fan unity on an inverter drive and it wouldn’t run, inverter kept showing fault. Motor checked out fine,Rewind company insisted it was the inverter,so swapped drives over in the panel with one of the others and just same. Original motor back ( after a bearing swap) and it ran fine. Never got any feedback on what the fault was with the rewound motor. Some of these new inverters do all sorts of tests before they even attempt a start.
Yea I have motors that’s just won’t work even though they test ok , not gonna stop searing , it’s it’s not for you don’t watch
@@Actual_electrical_content Bang right mate.
AC machines always follow the rules of physics. Chances are one of the field windings was incorrectly phased - i.e. the start of winding mislabeled an end e.g. U1 marked U2. You find people fukup connection of transformers this way.
The motor rewinder knows this can happen, but probably doesn't know modern VFD can recognise an out of phase winding prior to applying full start potential.
Find an honest rewinder, instead of one that knows the FU and tries to cover their errors by blame another component and wastes your time.
On a schematic the start of the transformer winding will be marked with a dot. It's rarely indicated with a motor because everyone assumes the rewinder knows what they are doing and tests their work. It's not always easy finding the start of a winding by visual inspection.
The real concern is that a probably unqualified individual was changing an industrial AC machine. No doubt there was ZERO testing of the motor or wiring prior to energising.
Have you no safety standards there, when any 'too smart by halves' unqualified dickhead can work on such machinery and not perform tests of their work?
I've seen the outcome... idiots using Earth as Neutral for motor starter control wiring when they bought the wrong contactor coil (240V and not 415V)
and the connection lead/plug having only 3p +E, rather than 3p+N+E.
This shit happens when any idiot mechanical fitter works on electrical systems.
Yeah, true GigOhms is only relevant with high voltage installations. The better way is to measure leakage current when doing HV testing at 10x operational voltage.
Great video Jamie. I spent years doing DAR and PI tests all over the world during my Megger days. I reckon we should discuss the subjects over a few beers 😊
you know where i am
What is the good and bad ohm measurement for windings? What is a good insulation reading in Mohms? I've been told anything under 3 mego ohms is bad. I'm not sure about the resistance readings for the windings. I've seen bad motors in the kohms.
Hi jamie brilliant video, much needed here on TH-cam! A couple of years ago i had the pleasure(!!!!) Of working in a garage where there was a single phase supply. Somebody had installed one of those big converters that generates 3 phase 😢 i wired in a small 3 phase compressor and no matter whether i wired it star or delta the motor ran very warm indeed! Is that normal? There must be limitations to these god awfull 3 phase generators? It was for an old mate so i was trying to be helpfull. As far as i know the garage didn't burn down.
An absolutely excellent video explaining the basics, many people in industry don’t get exposed to motors on a daily basis and may struggle but this video will teach them, I’m lucky I do motor circuits nearly every shift, my 2 sons are hopefully coming into trade and they will be watching this, so thank you for taking your time to do this, also good to see you looking less of a scruffy cunt and actually shaved 😂
What branch of the armed forces were you in
mate you made me larf, my son took a pic of himself standing inside an 11000 kw motor he had the rotor out of on a Carnival ship, he works for Sulzer in Australia
Thank you so much simple yet informative
What is the insulation on those test leads? You shouldn't be seeing that kind of leakage for a 500V test, you want to see >100.0 G with the leads open. For testing into GOhms you need silicone insulated test leads. On my CA6526, I can squeeze the leads together at 500V and get >100.0 G, at 1000V you see an initial drop but within 5 seconds or so you see > 200.0 G. You will get more leakage with PVC leads, but what you got there, still seems poor to me. I would try again with a new set of test leads.
When you are testing into the GOhms, any leakage has an affect on the reading and you will struggle to get consistency and won't be able to establish a trend. For trending, you also need to record winding temperature and ambient humidity, as they will also have an affect on the measurement. If the next test is carried out differently or in different conditions, you may see a lower reading, and think the motor is failing, but in reality it isn't.
Testing at GOhms for trending has its advantages as you indicated, but it is more prone to errors creeping in.
Cheers for the info , I’ve got some better leads but if I used them it wouldnt leak , remember this is still TV and some things are set up
Also it shows your in your comfort zone with these number That you picked up on that stright away , I am still trying to get my head around gig ohms it’s just some big number I don’t really comprehend at the moment
Often do this in hazardous areas, do the continuity of the windings in the field, then connect it up and meggar it from the switch room.
Could use the conductance instead of resistance. Fluke 87 can read nS or nanosiemens. It's strange to wrap your head around because the DMM reads 0 when the leads are open, and above 60 nS or below 16.6667 MΩ, it reads OL. 0.01 nS = 100 GΩ. All with low voltage.
My 87 V MAX is MSHA approved for hazardous methane environments.
thank you very much. absolute master piece tutorial.
You're very welcome!
Thanks, great video
Looking forward to the following videos, very helpful
Glad you like them!
Hi.its Amazing video..Just a question, dont we put 1000 v dc for IR test btw phases
1000 or 500 is fine
Great work mate,nothing wrong with throwing a few fucks around 😆
Very well explained. Thanks mate
Great video! 😊
Thanks for the visit
Good video, nice to know the correct way to test motors 🙏
Weird hearing you not swear, bet that was a F##k### struggle 😂
Great demonstration Jamie
Glad you enjoyed it
Spot on, can you do ex inspection on motor.
as in explosives environment?
@@Actual_electrical_content yes mate. As in Compex. Atex inspection.
@@118ball118 hi mate i am no longer atex qulifed and for that reason would not put it up
@@Actual_electrical_content ok buddy. Cheers.
Keep up the great vids by the way.
@@118ball118 only as long as you keep watching them
A great video thank you
I want to see the nest testing master
Pretty fucking good stuff, Jamie! I'm following up behind an HVAC tech that condemned a VFD, but I can't confirm if the motor itself is any good or not. I tried re-routing the line into the VFD directly to the motor but I used the the lugs on the motor output side of the VFD to do it, and the motor just buzzed and didn't spin. I don't know if this is a result of having the VFD in the circuit at all, but I'll isolate and go direct to the motor with the line volts (208/230 3ph) Guess I better check if they have the motor wired correctly as well. But I'll be thoroughly testing and drawing it up. Thanks for the vid!
Holy fuck this video clearly explains everything I’ve been confused about. I was hooked from the moment you insulted your potential viewers. Thanks mister. 🙏
I use paint markers on cables and terminations before I disassemble and a magnetic tray to rest my nuts in.
You need to rest your nuts on a tray?
F..k me! Is your name Buster Gonad? Viz is making a come back!
Super F*** instruction ! THANKS.
Hi mate,
Have just come across your channel and really enjoyed this explanation, but not a sparky just interested...
When i measure the IR between the windings of a 3ph motor on my MFT at 50/250/500V, it gives me a dead short (O ohms)...but when using a regular DVM it gives me around 4-5ohms ...is this normal? If so why?
Is that with the plates removed and the windings open ended
@@Actual_electrical_content should have mentioned -
I’m measuring between phases on the supply side - it’s basically a star wound motor (no neutral) connected to a Variable frequency controller for a submersible turbine pump … no access to motor from above ground
So essentially I’m meggering at the VFC output which includes the motor windings and the supply cables of the phases… giving me the above results…
Oddly, the bumps just moved from the left side of his face to his right side on his face.
A cell phone photo is superior to a drawing. Ron W4BIN
DO you have to discharge the windings after you test them?
Normally your meter take care of that
Ok cool, I work as a industrial electrician. Some other electricians give me crapfor not discharging windings after megging a motor😮
@@travisoroke174 Seriously, you trade training didn't cover BASIC test procedures? Do they let any unqualified/untrained individual work on industrial power equipment in that country?
There are no capacitors (run or start) in a 3p induction motor... you should know that, and where you do find caps to discharge.
Do the qualified electricians there send you to the electrical wholesale shop to buy a 'box of short circuits' or 'a long weight (wait)'. I would.
Great video
Thanks for the visit watch all of them
Great video, just came across it, you made it so fucking funny to watch, iv got experience with all sorts of traction motors blaa blaa, dont want to bore u lol, and your bang on with the info, keep great work up thanks
Please note me with your tales of different motors , o feature a dupe wound motor in my latest video about a mill repair
@@Actual_electrical_content i work on rail, most of the motors i work on are traction motors, dc shunt , series wound motors with interpoles, controlled with field diversion
Brilliant!
Not as brilliant as you Terry
Thanks
No problem I’ll spend that on booze
Proper content 🤔
If I wasn't available and my boss had this guy come out, I'd feel bad for him, and I don't like him very much
See you have a boss , I am the boss
the windins
LOL. You call 500V insulation test "spicy" voltage.
What do you call 2.5kV or 220kV testing? i.e. 10x working voltage potential.
In the field, you may as well bridge all windings and in a single test measure all to Earth in one move. In practice, that will indicate a fault and the motor is taken out of service for rewind.
This video is incorrect how to test motor for Insulation Resistance. Insulation Resistance on motor is done by Polarisation Index PI.
That’s a more complex method that I’ll probably cover at some point this video is for basic skills
Les tonk more working bos
You know the other fault that can occur when an unqualified idiot swaps out an obviously burned 3p motor with a spare that kinda fits?
Assume they get the Star or Delta connection right... perhaps. Assume they get the direction of rotation right and know how to correct that... perhaps.
The idiot installs a 2 pole motor when a 4 or 6 pole is needed, and wonder why the machine doesn't work correctly.
This shit happens.
Not a synchronous motor. It's an induction motor.
I meant to say squirrel cage
SCIM.. probably 4 pole. It be synchronous.
Needs 3 p AC - 120deg phase angle... maybe 50-60-200-400hZ
You find 1phase squirrel cage Induction motors too. They come in a variety of stator winding types, shaded pole, Cap start, Cap start/run. They need this to get the motor biased for rotation and direction. They be synchronous too.
They (IM) all rotate at a synchronous speed according to number of poles and supply frequency.
These all have 'squirrel cage' conductors in the rotor.
It's a given they are all induction motors with the rotor 'windings' as such.
Didn't your mum ever teach you it isn't polite to talk with food in your mouth 😂
What’s a mum ?
Why you need to use the f word all the time
If you don’t like it don’t watch , but it mainly it is because if you don’t your videos get stolen and used in Training courses by companies