What an excellent find! I appreciate the pacing and just the right amount of information to get you going without being overwhelming. Extra props for being so active in your comments. I'm looking forward to checking out all you have to offer. Thank you, good job and keep up the good work!
Thank you very much for the video It is a very good demonstration. 1) Could you please confirm though an easy way to measure correctly /accurately 180 degrees on the part indicated. 2) In the 2nd test are you checking comparing the 1st with 2nd (and) the 2nd with the 3rd and so on OR the 1st with the 2nd (and) the 3rd with the 4th and so on. I look forward to your reply From a Learner Thanks
Hi John, 1) for the 180 test, value itself is not important, consistency is. I usually mark on the commutator the start and 180 position and check every time I have landed on the right slot. 2) For the bar to bar test, go 1 to 2, 2 to 3, 3 to 4, etc The idea is to check if their is unbalancing across the wiring, which indicates an issue impacting the engine to properly turn. 180 test or bar to bar is simply to make sure a similar portion of the wiring is checked every time. Hope that clarifies.
I was out driving my 1944 GPW ford jeep. I noticed the amp meter was not working, reading zero. I decided to head home as i became worried. The amp meter needle then moved into the negative side of the guage which indicaded the battery was been drained on energy. After a while the needle moved to show a positive charge. i thought ok, all good, jeep has fixed itself. 😅👌🏻👍🏻. As i continued along home, suddenly the amp meter went totally crazy. The needle was flicking from side to side, the higher i reved the engine, the more violently the amp meter needle flicked from side to side. 🤤😓😭😭. I made it home ok. My jeep has a 12 volt system. New external voltage regulator & battery installed 3 months ago. I didn't know what to do or where to start. I found your video , thank God. Removed the generator/stripped down. Generator internals were filthy/full of dried dirt/dust as if it was dropped in mud for 6 months, then installed in the jeep. Probably dirt from world war 2, 😅🤣. Completely cleaned the internals with contact cleaner aresol, housing/armature/commutator. Surprisingly the 2 brushes had probably 60 to 70 % left.. Cleaned commutator bars where the brushes make contact with 800 fine grit paper. Commutator bars came up like new. Filed the brush surface that contacts the commutator bars with a file, so it was flat for better surface contact with the commutator bars. Done 3 tests on the armature as per your instructions. 2 ohms & 1 continuity tests. Armature passed the tests with flying colours. I assembled generator/ installed in jeep, left the fan belt off the generator. To test the generator, i connected a wire between field terminal & armature/dynamo terminals on the generator . I then ran a 2nd wire from the positive side of the battery to the wire that connected both terminals on the generator. The negative lead must be connected to the battery. The pulley spun on it's own indicating it was working properly. Connected up wires, started jeep engine. Reved the engine to approx 700 to 900 RPM, amp meter needle moved across to the positive charge on the amp meter. Tested battery charge rate was 14.2 volts at approx 700 to 900 RPM. All the problems were caused by a gut full of dirt in the genny, 😅🤣😂 Thankyou for sharing your information, really got me out of trouble. 😂🤣😅👌🏻👍🏻👏🏻👏🏻👏🏻 Cheers from 🇦🇺
To perform this test properly, a four lead, low ohms meter is required at minimum, and much better to use a growler. To properly test for grounds between the windings and the Core, a megger is really required, or at very least set your meter to the Highest ohms setting, Not the lowest. The insulation test need only be performed between ONE commutator bar and the armature Core, because All commutator bars are connected together!
"The insulation test need only be performed between ONE commutator bar and the armature Core, because All commutator bars are connected together!" yeah thats the right way.i think he has no idea what is happening
I used your instructional video to clean and test my armature. Can you tell me the easiest way to clean the shavings from inside that are attached to the magnet? Thank you.
..my utmost thank you to you.. I have a gbh 4-32 that has been broken for a long time and I was thinking of throwing it away but after watching this video and a few other related videos on your channel, the machine is now working.. i subscribe..
Excellent video. Going step by step....again....again. Most youtube videos skip basic steps like setting multimeter before each test and you have to go back to beginning to see what is the multimeter set to . Same thing with measurements....taking two measurements after each other is perfect and enough to show roughly the same reading. Nice work, LabOtomy ! :-)
If you measure no bar to stack leakage on the first bar, shouldn't that conclude the test? Any leakage from the windings to the stack would show up on all of the bars.
Great Video! I have one question. In the first testing you had appx. 01.6 ohm and you said that there is resistence drop? How do you indicate that? For examle if you measure it and it jumps right away to 01.6 ohm instead of droping from 34.6 to .01.6?
I am not the author, but I am an electronics technician. The rate of drop is immaterial, as it is a function of the circuitry in the meter, and also any residual resistance at the contact points. Just wait, and use the reading when the meter settles. The term "drop" as applied to this test is about the amount of resistance in the armature winding, which will cause a voltage drop when power is applied.
thank you! using this test procedure now on a used motor i just bought.. do you know the difference in using a growler rather than this? does the growler induce more voltage to make shorts more noticeable? it seems as though this should work about as well.
The growler is a specialized device, so will be faster helping validating the quality of an armature insulation for eventual shorts... this said, being specialized, means it is less common than a standard multi-meter in a work-space... with the multi-meter, I also like to confirm the balancing of the coils, not sure if the growler can deliver on that (leaving the last open for any growler specialist to infirm/confirm on that statement)
thanks again! I ask because I have a motor I need to repair for my race car that is a bit hard to find, one of the people I called for help said a regular multimeter couldn't do the same job even good enough for me in my garage, considering this video and the fact that the part is mine, im going to test it this way and see how that works.
Is this available for cordless tools? today i replaced brushes on my 18 v, dga 452 makita angle cordless grinder, checked the armature (no short circuits), but after reassembling it doesn't run smooth or constant as new, after a few seconds the speed varies for a short period and it comes back again, but has enough power to cut someting. I noticed a little bit of play on the big bearing. What do you think? What should I do? Thanks in advance.
@@TheLabOtomy yes, I even clean with a fine sandpaper the copper contacts and replace the holder with a new one. I will replace soon as posible the 2 armature bearings with 2 new skf.
th-cam.com/video/b9XxlYusuR8/w-d-xo.html this is the grinder, I made a video today, it looses rpm in minute 0:25 and returns back for 30 sec, but still oscillate. Never ever dealed with this kind of problem and repaired a lot of my grinders.
@@TheLabOtomy I do care about my tools. I work with 20 power tools and 10 inverters/welders and I can't afford to throw them away and buy new ones. I repair what I can by myself or at a specialized shop and save a lot of money with a little bit of struggle 🤝🥂
One of the Best Tutorial DIY because he was Clear, non monotone, and easy to understand,and to the point without any bull. I would like to know: if I purchase a motor followed hooked up wiring as per direction from rear ran fine for about one 1 min then slowed down , this is to a compressor that has ben running for 16 years so power to the power switch is more than fine. Help me. Ps this is the second motor in two days from harbor. Freight Smith and Jones 3hp
Great video - has got me thinking! Hi, testing a 6-pin universal 2-pole Bosch washing machine motor (Bosch front loader). The motor had previously seized due to a failed armature bearing. Replaced both bearings on the armature. I then checked the motor for continuity through windings, thermal fuse, to the carbon brushes and through the tacho - all appeared good according to the DMM. So, reinstalled the motor in the machine and tested, but now the motor fires up and spins the drum as you would expect, but only for just a second or so before it stops (this happens for wash, rinse and spin)??? Could this be a commutator issue as per your tests above or would any failings (shorts) here cause the motor not to spin at all)?
@@alloverflorida5886 Thanks my friend! I know where the start capacitor is and I checked it for obvious signs of failure early on - not sure where the run capacitor is though?
My vacuum cleaner turns off after about 20 seconds, and if I keep using it that time goes down, I gotta wait about a minute in between, It also happens when I hook the motor directly too power, brushes are good, would you have any ider where I could look next.? TIA.
Gracias por brindar tus conocimiento! estoy reparando un cepillo eléctrico makita y todas las pruebas tengo luz verde, pero aun así chispea mucho el inducido al prender la maquina, lo que noto es una decoloración en algunas delgas y no hay ninguna delga levantada para presentar esta chispa, mi conclusión es que hay algún corto interno entre las delga del inducido pero no en el cableado de las bobinas.,
General question a starter motor I'm troubleshooting has four brushes each separated by 90 degrees. The brushes as 12 o'clock and 6 o'clock are positive and brushes at 3 o'clock and 9 o'clock are negative. If the armature windings terminate at commutator segments that are 180 degrees apart. How is there current flow? It seems like both ends of the armature windings would be at the same polarity at any given moment. What am I missing?
Thank you SO much for posting this video. I have an vintage sewing machine that is not starting up when I plug it in. Hopefully it's a short in the wires or wires not connected properly and not the commutator/aperture.
So I switched on my vacuum and it began to smoke. I checked the commutator bars with the lowest resistance and in the four of the tests the resistence couldn't settle on a reading: it would spikes and even show "OL". I didn't need to test given the smoking issue but wanted to know where the problem was. Thanks for the this lesson. It was straight to the point.
You can Definately rewind the wires and use it again. The main problem isn't burnt wires, but the alloy, assembly itself, if it's still in good shape. Electric motors usually have an air cooling fan to them. Sometimes a heat sink or heat resistant shroud , thicker wires can pro long their use. How they short outs, perhaps small metal debris,melted resin, from heavy use .
Difficult to assess without knowing the specifics, but a motor traditionally overheats because it pulls many amps, this due because it has to work hard. This could be due to the operations being conducted (i.e. mowing high grass), or due to mechanical restrictions (worn off bearings, or stuff stuck in the blade). Hope it helps
@@TheLabOtomy hello sir As i tested same u told in video We have 180v dc motor rpm is 1000.....rpm is flacuating around 300+or-.when rpm is 1000 1. Cleaned the comutator. 2.fixed new carbon brush 3.at starting rmp is constant after when carbon brushes are slightly corved inside starts flactuating Thank u
Is it ok to do these tests with the armature still mounted in the motor casing with the brushes removed? for insulation test is it ok to just use the motor casing or center shaft instead of the iron stack? should all be connected right? I work on treadmills and removing the armature is wayyyy too time consuming - need a faster way to test motors...
As mentioned in my other answer to your questions, there is no 1 answer as all motors are different (in number of winding loops, winding design & patterns, motor sizes, winding wire gauges etc). If you really need a value, those should be found in the product specs (if available)
Good video. Mostly when i see the Armature of an electric motor ? Is when my Angle Grinder stops working. IF the bushes are worn replace them. If Not worn, and the commutator is worn. Then in the bin it goes and off to buy a New Angle Grinder, LOL.
awesome track man. it's killin me tho. was a dj for close to 20 years (tribal house, breaks, dnb, later some dubstep -i dislike joining bandwagons when they're in full swing). anyways, I stopped paying attention to the video itself and am now lost in good feelings and love of times past. thank you :) ..oh yeah, I'll make sure to watch the video again to learn some electronics :) -Art (djseek/ASF, Santa Cruz, CA)
I'm trying to fix a paper shredder motor, it has one of those rectangular thin plates missing and it caused the brushes to go out of place due to the gap. Is this fixable ? What should I do ?
Constant contact with the brushes is essential for good motor operations, so unless you can figure out how to replace (build one yourself?) the missing piece, the shredder will not operate properly...
@@TheLabOtomy I think that rectangular thin plate missing it's called the commutator. From what I understand, one (or two) small wires should be connected to it (or a single wire passing thru it, since it was ripped off I ended up with 2 wire ends. This is too small to see properly, need to check better with a magnifying glass, but I think the commutators have a wire passing thru them, right ? I could try to get a pice of copper and shape it to fill the missing gap and connect the wire(s). This is an AC motor 220v, not sure if soldering the wire(s) to the hand made missing commutator, glued with high temperature epoxy would withstand the temperature when working. What do you think ?
I have this exact looking motor on a drill press. When I power it on it hums a little at 0 speed but if I try to increase the speed it shuts my whole press off due to some kind of over temp protection.
Algunas personas son especialistas en la revisión de motores eléctricos y pueden reparar un conmutador averiado. Comprar un reemplazo también es una solución.
Congratulaciones, sólo hablo español. Espero me puedan entender; a pesar de todo pude entender algunas cosas. Eso quiere decir que es muy explícito. De nuevo gracias
Hallo sir i got a small black and decker drill with a ten millimeter chuck it runs with a deep noise and very slow,what can be faulty or how can i fixed it
@@lyndontinonga8576 you may be completing the circuit with your skin if you are touching the probes. I keep accidentally doing that, and have to remind myself.
Hello. Is 1.5 Ohm usual for all motors? Should I only have a current flow of 180 °? Installed in the motor, it is not easy to identify the correct contacts. I am using a metrix MX 355. An ammeter with a combined flow test and ohmmeter. I measure a flow of 4.3-5.3 ohms between many contacts. Do I have to measure all opposite contacts? So far I have found a pair of opposing contacts with no flow. The carbon contacts are as wide as two contacts on the armature. I have the problem that a Sebo Felix vacuum cleaner with Ametek Italia e063200099 1200W motor with good long coals suddenly stopped working. When I put the motor out of the device, it ran sometimes. But not always. Like a loose contact. But one thing is certain, it is not the supply lines, they also have power when the motor is not running. I cleaned the contact surfaces of the anchor and the coals with a bath lime cleaner with sulfamic acid and then solvent, and tried again. Same as before. I can't say whether the "fire" is stronger now. But it seems very strong compared to the Wikipedia video. Is the engine over and need to be replaced? Because a replacement anchor (if it were) is probably not available for purchase. If I make the effort to pull the sheet of the fan chamber down, I could remove the anchor. If I knew where I could get a replacement engine ... Also used. For example, with the names of other devices that contain this motor.
The idea of the 180 test is that you cover the same wire length each time, hence the need to choose consistent pairs of commutator contacts. Any variation around that test is an indication there may be internal shorts and would require either the armature to be replaced or serviced/rewired (specialised work).
Yes, sorry, that is what I meant, those slots are made to perfectly balance the "armature: on a car you add small weights to balance a turning wheel, here since you cannot add anything, you shave off (well the machine does) the unbalanced weights until the armature spins without any wobbles.
My multimeter indicates 0.4 ohm resistance between probes and between commutator segments, so resistance cant drop more. How should i know if there is short between coils?
Best video on this topic. And a nice disclaimer. My field is black and has almost no insulation left. The armature has one suspicious coil. All of them are 0.3 to 0.5 but one is 0.6 , could it be normal or could this even be the reason why the field overheated? I dont know nothing obout the provious use of the mashine. It's a 15yr old dewalt but the blade was pretty dull.
So, a possible scenario in your case could have been: 1) Blade is dull, which causes 2) Motor to have to work harder, which causes 3) Motor to pull more amps, which causes 4) Armature coil to heat up beyond normal, which causes 5) Damage to the internal wiring (resulting in resistance discrepancy within the machine coils, 0.3 to 0.6 is a 100% variation which is real source of concern) and degradation to the insulation material (burning through and truning black) 6) Which causes the motor perceiving a loss of power to go back to 3) for a ultimate catastrophic failure The Cause and effect theory at its best!
@@TheLabOtomy I could not have explained that better. Got an old dremel here that's got the same variance. I just happen to have some rolls of magnet wire that's just a little thicker than what's on it now. Time to rewind the armature and field core. Why would I do this? Because I can!! And just a little payback for pissing me off and failing when I needed it most! And from what I understand this particular model is known for this failure, and I am surprised that with this being a flex shaft only model they would have used a better quality wire and cooling fan! In any case, Thank you for this informative video👊
Probably caused by dirty commutator bars. Use 800 grit sand paper on the commutator bars. When using sand paper, turn armature in one continous direction, not backwards/forwards is always best, 👍🏻👌🏼
If dc motor you can retard the timing as ive had brand new hobby motor sparking like hell and running extremely hot but after lifting the endbell tabs rotating anti clockwise to drop rpm the motor worked like it should!
There is no good or bad resistance (number of winding loops, winding design & patterns, motor sizes, winding wire gauges can all vary), it is all about being balanced across all segments so that the electromagnetic forces exercised are consistent to ensure a smooth rotation.
@@TheLabOtomy If the laminate comming on wire is damaged then would itbe possible for a number of windings to be shorted to it's neighbouring windings?
what would cause an impact drill to continue spinning a few seconds after letting go of trigger? Bad trigger switch? Any ideas? btw this was a great vid
Any experience with a starter that engages but seems to not have enough power to actually move the engine? Already checked for a bad ground, and all connections related to the starter and solenoid. Verified there is no weak connections. Solenoid contacts switch as designed. Brand new battery 2 days old. 2nd battery by the way. Lights dim big time as the starter engages then stops, as if the engine is seized. Ran fine the day before this issue arrived. lol Woke up to leave and discovered this problem. I have not removed the starter yet. But I do suspect possible armature burn and/or brush damage. Just not sure if one could cause such a MASSIVE power draw like this while never turning more than what seems to be an inch or two at most. Could I be experiencing a less common commutator-armature stack short?
Well, that is now on the top of the list of "toys" for the garage. lol Thank you for the response!! Well, starter removal it is now. Worse case, I find out the problem is not with the starter. Someone had mentioned a "dry" cylinder. Oil drained from the cylinder walls as it cooled, which caused one or more pistons to stick to the cylinder walls. Any knowledge in that area? Before I start spraying lube into to cylinders anyway. lol (oil light never came on, but I found I was abnormally low on oil.) NEVER heard any ticking or noise from the engine at any point. No shudders or lunges. Just smooth running one day, and no movement the next.
busilica123 My thoughts on the engine as well. Someone mentioned possible head warping as it cooled off. Others say the pistons swelled, which I know to be incorrect. One thing is certain, I can not get the engine to rotate even when trying to push it using all gears. I get the rear tire sliding only. Granted, I am not on the bike while trying to "push start" it. Perhaps there needs to be weight on the bike to prevent the tire from sliding. I have never had this happen before. And that includes my fist bike. (I was horrible with maintenance back then) It overheated a few times but never "seized" like this. This bike has been babied. It is almost a sacrilege for me to own this bike, as I never even come close to using it's full potential. Just wish I knew why it started fine that morning, but the next morning, nothing. And it is for sure the starter draining the system. I removed the starter from the circuit and hit the button. The fuel pump and all lights ran as normal. Now I am praying there is a bolt inside the crank case so I can try to rock the engine loose. (If seizure is my issue)
could be short circuit or worn brushes, or even magnets breaking up and stopping rotation, i have experienced all of these, plus ingress of water can do this and create shorts in the electrical components. hope this helps. may the force be with you
I have several broken motors, and I find this video instructional because at least I can tell for certain that the motor is irreparable, (something that I already well figured out, as the vacuum cleaner does not clean and the hair dryer does not move air). The video is very well done (artistic, indeed), and I've been hoping it could give me a hint on how to fix the coils by the bottom stack, but I don't think this is feasible with my limited capacities. Like an egg and myself, my coils and brain are fried, it seems... Nevertheless, the little funnies help me shed off the tears of what is now just a lump of metal... Next, LabOtomy, sir, would you kindly show us how to actually *fix* the f'in thing? Much appreciated, D.P.
Hi,ive taken the brushes out of my washing machine and moved the motor to the bench,the armature only moves about 5 mm to the left and to the right,and it cant move either way any more,any help please what may be wrong,
I could be wrong but to me, fuse blowing would indicate an issue with another section of the machine, like damaged wiring or a blown decoupling capacitor
@@TheLabOtomy the motor is for hand blender dc 220v the fuse doesn't blow when motor disconnected but when i connect motor and turn it on motor runs for 3 seconds then spikes and blow the fuse
Thanks for the super informative video :) , i have a Ryobi circular saw which lost about 80% of its power on me while cutting a piece of wood and everytime i use press the button to power it loads of sparks come out of between the brushes and the commutator bar,( the brushes have loads left on them ) so after watching this video i dismantled it and did the above tests and it passed on them all except on test no.2 where all my readings were 0.2 between each adjacent commutator bar EXCEPT one reading which was 2.3 instead of the usual 0.2 , so i take it this means i either need a new armature or scrap the saw ??
Hm, sparks but brushed big enough, 80% power of power loss and a 10 fold variation on bar-to-bar resistance test, seems we are getting all the signals of an armature coil saying "I shall live no more"
May i add, your 3rd Test should also been done on Meg Ohm scale, reading should be higher than 1 megohm. Don't touch the probe ends as you will false readings
i have a small electric motor on a child toy peg pelegro polaris. one motor is fine, the other does not have power. Took them off the gear mechanism, both turn, but one stops as soon as power is disconnected, and the other spins freely. no mechanical resistance. lube does not help. i took apart the the bad one, one coil is darker, obviously overheating. but not shortened. i measured the resistivity of all 3 coils, they start at 3-4 ohmes, then quickly reduce to 0.8 ohm. makes sense. Any idea, what is wrong with this motor? I bought a replacement, but this is my curiosity tickling me.
Dark is a bad sign, heat can cause isolation material to internally fail and the coil to propose a shorter electric path (implying a different magnetic field is generated that may longer cause the motor to improperly turn)
Hi.. i have a craftsmsn router keeps turning off due to sparks..i took apart and filed the commutator good on a lathe and then i flattened the brushes good and now it works a bit better but powers off at high rpm setting...sparks...anyone have any suggestions..brushes are about 1/2 in long
Hi Sir, need your help regarding "Drop In Resistance" & "Resistance Spike", what this mean..? I'm from Malaysia, like to learn about service & repair as you do.. :-)
Can anyone tell me why is there continuity between the comutator segments? Why are motors built this way? I thought comutators were suppose to separate the current, sending it through a different coil every time the brushes jump to the next segment?
Straight to the problem, no bullshitting, watching the video solves all your problems. Thanks! ❤
Thanks for the feedback
What an excellent find! I appreciate the pacing and just the right amount of information to get you going without being overwhelming. Extra props for being so active in your comments. I'm looking forward to checking out all you have to offer. Thank you, good job and keep up the good work!
Thanks for the kind words, hope you will find something of interest in the channel
Best presentation of this kind I've seen on YT. Congrats! :)
Thanks for the positivity!
Thank you very much for the video It is a very good demonstration.
1) Could you please confirm though an easy way to measure correctly /accurately 180 degrees on the part indicated.
2) In the 2nd test are you checking comparing the 1st with 2nd (and) the 2nd with the 3rd and so on OR the 1st with the 2nd (and) the 3rd with the 4th and so on.
I look forward to your reply
From a Learner
Thanks
Hi John,
1) for the 180 test, value itself is not important, consistency is. I usually mark on the commutator the start and 180 position and check every time I have landed on the right slot.
2) For the bar to bar test, go 1 to 2, 2 to 3, 3 to 4, etc
The idea is to check if their is unbalancing across the wiring, which indicates an issue impacting the engine to properly turn. 180 test or bar to bar is simply to make sure a similar portion of the wiring is checked every time. Hope that clarifies.
I was out driving my 1944 GPW ford jeep. I noticed the amp meter was not working, reading zero. I decided to head home as i became worried. The amp meter needle then moved into the negative side of the guage which indicaded the battery was been drained on energy. After a while the needle moved to show a positive charge. i thought ok, all good, jeep has fixed itself. 😅👌🏻👍🏻. As i continued along home, suddenly the amp meter went totally crazy. The needle was flicking from side to side, the higher i reved the engine, the more violently the amp meter needle flicked from side to side. 🤤😓😭😭. I made it home ok. My jeep has a 12 volt system. New external voltage regulator & battery installed 3 months ago. I didn't know what to do or where to start. I found your video , thank God. Removed the generator/stripped down. Generator internals were filthy/full of dried dirt/dust as if it was dropped in mud for 6 months, then installed in the jeep. Probably dirt from world war 2, 😅🤣. Completely cleaned the internals with contact cleaner aresol, housing/armature/commutator. Surprisingly the 2 brushes had probably 60 to 70 % left.. Cleaned commutator bars where the brushes make contact with 800 fine grit paper. Commutator bars came up like new. Filed the brush surface that contacts the commutator bars with a file, so it was flat for better surface contact with the commutator bars. Done 3 tests on the armature as per your instructions. 2 ohms & 1 continuity tests. Armature passed the tests with flying colours. I assembled generator/ installed in jeep, left the fan belt off the generator. To test the generator, i connected a wire between field terminal & armature/dynamo terminals on the generator . I then ran a 2nd wire from the positive side of the battery to the wire that connected both terminals on the generator. The negative lead must be connected to the battery. The pulley spun on it's own indicating it was working properly. Connected up wires, started jeep engine. Reved the engine to approx 700 to 900 RPM, amp meter needle moved across to the positive charge on the amp meter. Tested battery charge rate was 14.2 volts at approx 700 to 900 RPM. All the problems were caused by a gut full of dirt in the genny, 😅🤣😂 Thankyou for sharing your information, really got me out of trouble. 😂🤣😅👌🏻👍🏻👏🏻👏🏻👏🏻 Cheers from 🇦🇺
Thanks for sharing. happy to read it has been helpful
To perform this test properly, a four lead, low ohms meter is required at minimum, and much better to use a growler. To properly test for grounds between the windings and the Core, a megger is really required, or at very least set your meter to the Highest ohms setting, Not the lowest. The insulation test need only be performed between ONE commutator bar and the armature Core, because All commutator bars are connected together!
sounds good. Please make a video for us with more explanation!
"The insulation test need only be performed between ONE commutator bar and the armature Core, because All commutator bars are connected together!" yeah thats the right way.i think he has no idea what is happening
to debil, nie ma mu co tłumaczyć, i tak nie zrozumie
I used your instructional video to clean and test my armature. Can you tell me the easiest way to clean the shavings from inside that are attached to the magnet? Thank you.
Gently brush them off
very informative video and very good edited. Thank you
Thanks
..my utmost thank you to you.. I have a gbh 4-32 that has been broken for a long time and I was thinking of throwing it away but after watching this video and a few other related videos on your channel, the machine is now working.. i subscribe..
Nice Angelnoheart, always good to hear about people fixing their stuff!
Excellent video. Going step by step....again....again.
Most youtube videos skip basic steps like setting multimeter before each test and you have to go back to beginning to see what is the multimeter set to
. Same thing with measurements....taking two measurements after each other is perfect and enough to show roughly the same reading. Nice work, LabOtomy
! :-)
Thanks for the feedback Peter X, appreciated
Hi great video, how much variance in resistance is acceptable?
Plot the data and see if there are odd spike values or if the chart looks homogeneous
@@TheLabOtomy podrías indicarme como realizas la grafica? Gracias por tu ayuda!!
The format, the graphics, the contents and even the music is very clear and amusing, great !
Thanks for the feedback
Excellent tutorial I have learned something new today - always a good day!
Thanks for the feedback
If you measure no bar to stack leakage on the first bar, shouldn't that conclude the test? Any leakage from the windings to the stack would show up on all of the bars.
Great Video! I have one question. In the first testing you had appx. 01.6 ohm and you said that there is resistence drop? How do you indicate that? For examle if you measure it and it jumps right away to 01.6 ohm instead of droping from 34.6 to .01.6?
I am not the author, but I am an electronics technician. The rate of drop is immaterial, as it is a function of the circuitry in the meter, and also any residual resistance at the contact points. Just wait, and use the reading when the meter settles. The term "drop" as applied to this test is about the amount of resistance in the armature winding, which will cause a voltage drop when power is applied.
Thank you so much for your video, helps maintenance students a lot
Happy to help
thank you! using this test procedure now on a used motor i just bought.. do you know the difference in using a growler rather than this? does the growler induce more voltage to make shorts more noticeable? it seems as though this should work about as well.
The growler is a specialized device, so will be faster helping validating the quality of an armature insulation for eventual shorts... this said, being specialized, means it is less common than a standard multi-meter in a work-space... with the multi-meter, I also like to confirm the balancing of the coils, not sure if the growler can deliver on that (leaving the last open for any growler specialist to infirm/confirm on that statement)
thanks again! I ask because I have a motor I need to repair for my race car that is a bit hard to find, one of the people I called for help said a regular multimeter couldn't do the same job even good enough for me in my garage, considering this video and the fact that the part is mine, im going to test it this way and see how that works.
A grower is the best way
Is this available for cordless tools? today i replaced brushes on my 18 v, dga 452 makita angle cordless grinder, checked the armature (no short circuits), but after reassembling it doesn't run smooth or constant as new, after a few seconds the speed varies for a short period and it comes back again, but has enough power to cut someting. I noticed a little bit of play on the big bearing. What do you think? What should I do? Thanks in advance.
Are the brushes properly / securely seating and making good contact with the commutator?
@@TheLabOtomy yes, I even clean with a fine sandpaper the copper contacts and replace the holder with a new one. I will replace soon as posible the 2 armature bearings with 2 new skf.
th-cam.com/video/b9XxlYusuR8/w-d-xo.html this is the grinder, I made a video today, it looses rpm in minute 0:25 and returns back for 30 sec, but still oscillate. Never ever dealed with this kind of problem and repaired a lot of my grinders.
@@calinsandor9518 Good to see there are still people taking good care of their stuff! Repair Reuse Recycle!
@@TheLabOtomy I do care about my tools. I work with 20 power tools and 10 inverters/welders and I can't afford to throw them away and buy new ones. I repair what I can by myself or at a specialized shop and save a lot of money with a little bit of struggle 🤝🥂
gracias por el tiempo que le dedico a hacer el video, muy útil la información.
One of the Best Tutorial DIY because he was Clear, non monotone, and easy to understand,and to the point without any bull.
I would like to know: if I purchase a motor followed hooked up wiring as per direction from rear ran fine for about one 1 min then slowed down , this is to a compressor that has ben running for 16 years so power to the power switch is more than fine. Help me. Ps this is the second motor in two days from harbor. Freight Smith and Jones 3hp
Great video - has got me thinking!
Hi, testing a 6-pin universal 2-pole Bosch washing machine motor (Bosch front loader). The motor had previously seized due to a failed armature bearing. Replaced both bearings on the armature. I then checked the motor for continuity through windings, thermal fuse, to the carbon brushes and through the tacho - all appeared good according to the DMM. So, reinstalled the motor in the machine and tested, but now the motor fires up and spins the drum as you would expect, but only for just a second or so before it stops (this happens for wash, rinse and spin)???
Could this be a commutator issue as per your tests above or would any failings (shorts) here cause the motor not to spin at all)?
Sounds like the start capacitor is working but the run capacitor has failed possibly
@@alloverflorida5886 Thanks my friend! I know where the start capacitor is and I checked it for obvious signs of failure early on - not sure where the run capacitor is though?
@@intestinalworm1202 many times they are both in the same case.
My vacuum cleaner turns off after about 20 seconds, and if I keep using it that time goes down, I gotta wait about a minute in between, It also happens when I hook the motor directly too power, brushes are good, would you have any ider where I could look next.? TIA.
Great video I have a bunch of Tecumseh Snow King starters to check.
Good luck
Gracias por brindar tus conocimiento!
estoy reparando un cepillo eléctrico makita y todas las pruebas tengo luz verde, pero aun así chispea mucho el inducido al prender la maquina, lo que noto es una decoloración en algunas delgas y no hay ninguna delga levantada para presentar esta chispa, mi conclusión es que hay algún corto interno entre las delga del inducido pero no en el cableado de las bobinas.,
General question a starter motor I'm troubleshooting has four brushes each separated by 90 degrees. The brushes as 12 o'clock and 6 o'clock are positive and brushes at 3 o'clock and 9 o'clock are negative. If the armature windings terminate at commutator segments that are 180 degrees apart. How is there current flow? It seems like both ends of the armature windings would be at the same polarity at any given moment. What am I missing?
Commutator segments are not, per se, connected on a 180 degrees direction. It all depends on the motor so can have many different configurations.
Thanks so much for your video !
It saved my day !
Best regards,
Good to read, thanks for the feedback
To test continuity to ground wrap a braided copper wire around the comm then measure from braid to stack ( ground) it is much faster.
Indeed!
if any of them are shorted to ground it will show in any of them, the resistence may be lower but any value other than open is bad
Thank you SO much for posting this video. I have an vintage sewing machine that is not starting up when I plug it in. Hopefully it's a short in the wires or wires not connected properly and not the commutator/aperture.
It's got a plug ? That's not vintage. Vintage is the Old treadle operated Singer machine my Mother used to rattle away on when we were kids. . . .
So I switched on my vacuum and it began to smoke. I checked the commutator bars with the lowest resistance and in the four of the tests the resistence couldn't settle on a reading: it would spikes and even show "OL". I didn't need to test given the smoking issue but wanted to know where the problem was. Thanks for the this lesson. It was straight to the point.
Yep, you found your fault!
I appreciate your video very much. Thanks.
Thanks MrKromy67
You can Definately rewind the wires and use it again. The main problem isn't burnt wires, but the alloy, assembly itself, if it's still in good shape. Electric motors usually have an air cooling fan to them. Sometimes a heat sink or heat resistant shroud , thicker wires can pro long their use. How they short outs, perhaps small metal debris,melted resin, from heavy use .
The commutator bar or the bit you was touching with the prongs. Mine is completely worn down. Does that mean I need a new motor?
This would need to be repaired at least, a specialized shop can refurbish that part if buying a new one is too much of an investment.
what causes overheating of starter on lawn mower., i have glued the magnets back not sure if they have to be in a certain way, mine had 2 magnets .
Difficult to assess without knowing the specifics, but a motor traditionally overheats because it pulls many amps, this due because it has to work hard. This could be due to the operations being conducted (i.e. mowing high grass), or due to mechanical restrictions (worn off bearings, or stuff stuck in the blade). Hope it helps
That was very helpful. Thank you!
Welcome
excellent video
Glad you liked it!
Very practical and helpful....thank you
Very clear and simple explanation. Thank you definitely helpfull.
Great to hear!
@@TheLabOtomy hello sir
As i tested same u told in video
We have 180v dc motor rpm is 1000.....rpm is flacuating around 300+or-.when rpm is 1000
1. Cleaned the comutator.
2.fixed new carbon brush
3.at starting rmp is constant after when carbon brushes are slightly corved inside starts flactuating
Thank u
Where is the location or your shop..
Second street left
Is it ok to do these tests with the armature still mounted in the motor casing with the brushes removed? for insulation test is it ok to just use the motor casing or center shaft instead of the iron stack? should all be connected right? I work on treadmills and removing the armature is wayyyy too time consuming - need a faster way to test motors...
With the brushes removed, that is ok
Very easy and convenient. Thanks
Thanks for the feedback Zaheer
Wow great vid all the info you need
Good to hear, thanks
Great explanation, clear and concise! Thanks!
So when I would did the bar to bar it went down from 1.4 to 1.3. not a big difference but it still changed. Does that indicate a problem?
no amigo, por ejemplo una diferencia entre una lectura y la otra podría ser 1.4 a 3.5, o valores que están mu separados, ya seria preocupante.
What should the resistance be after deducting the lead resistance?
As mentioned in my other answer to your questions, there is no 1 answer as all motors are different (in number of winding loops, winding design & patterns, motor sizes, winding wire gauges etc).
If you really need a value, those should be found in the product specs (if available)
Good video.
Mostly when i see the Armature of an electric motor ?
Is when my Angle Grinder stops working.
IF the bushes are worn replace them.
If Not worn, and the commutator is worn.
Then in the bin it goes and off to buy a New Angle Grinder, LOL.
awesome track man. it's killin me tho. was a dj for close to 20 years (tribal house, breaks, dnb, later some dubstep -i dislike joining bandwagons when they're in full swing). anyways, I stopped paying attention to the video itself and am now lost in good feelings and love of times past. thank you :) ..oh yeah, I'll make sure to watch the video again to learn some electronics :) -Art (djseek/ASF, Santa Cruz, CA)
Good to hear (WARNING / WARNING / This pun was intended... \ WARNING \ WARNING)!
Nice video good demonstration to test
Thanks Tyrone
I'm trying to fix a paper shredder motor, it has one of those rectangular thin plates missing and it caused the brushes to go out of place due to the gap. Is this fixable ? What should I do ?
Constant contact with the brushes is essential for good motor operations, so unless you can figure out how to replace (build one yourself?) the missing piece, the shredder will not operate properly...
@@TheLabOtomy I think that rectangular thin plate missing it's called the commutator. From what I understand, one (or two) small wires should be connected to it (or a single wire passing thru it, since it was ripped off I ended up with 2 wire ends. This is too small to see properly, need to check better with a magnifying glass, but I think the commutators have a wire passing thru them, right ? I could try to get a pice of copper and shape it to fill the missing gap and connect the wire(s). This is an AC motor 220v, not sure if soldering the wire(s) to the hand made missing commutator, glued with high temperature epoxy would withstand the temperature when working. What do you think ?
Seems like a delicate repair, but since the shredder is useless at this stage, may be worth a try
very well explained ... bravo ! ;)
Thanks Yves
I have this exact looking motor on a drill press. When I power it on it hums a little at 0 speed but if I try to increase the speed it shuts my whole press off due to some kind of over temp protection.
easy to follow video, great work!
Glad you liked it!
I have a drill, it’s motor has a cracked magnet, will this affect the performance?
Difficult to say without seeing the extent of the damage
Buenas Noches... en el caso de confirmar que la armadura esta dañada... La misma no tiene arreglo??? La solución es comprar una nueva???
Algunas personas son especialistas en la revisión de motores eléctricos y pueden reparar un conmutador averiado. Comprar un reemplazo también es una solución.
@@TheLabOtomy Gracias por darme alternativas, ya solucioné ;)
Gracias por los comentarios, bueno leer
I got resistance spike in bar to bar, can it be fix?
An important lesson, Thank you.
is it possibile to clean a commutator with fuel? mine it's flooded with black oil from the differential
Perfect 👌👍Thank you 🙏🌹
👍🌹
Congratulaciones, sólo hablo español.
Espero me puedan entender; a pesar de todo pude entender algunas cosas. Eso quiere decir que es muy explícito.
De nuevo gracias
Hallo sir i got a small black and decker drill with a ten millimeter chuck it runs with a deep noise and very slow,what can be faulty or how can i fixed it
Broken ball bearings?
In my case sir, 3rd test (continuity test). The reading is 1.1 mega ohms per test. What is the meaning of that reading sir? It is short or okay?
But in the 1st test and 2nd test are the same result and okay
@@lyndontinonga8576 you may be completing the circuit with your skin if you are touching the probes. I keep accidentally doing that, and have to remind myself.
Hello.
Is 1.5 Ohm usual for all motors?
Should I only have a current flow of 180 °?
Installed in the motor, it is not easy to identify the correct contacts.
I am using a metrix MX 355.
An ammeter with a combined flow test and ohmmeter.
I measure a flow of 4.3-5.3 ohms between many contacts.
Do I have to measure all opposite contacts?
So far I have found a pair of opposing contacts with no flow.
The carbon contacts are as wide as two contacts on the armature.
I have the problem that a Sebo Felix vacuum cleaner with Ametek Italia e063200099 1200W motor with good long coals suddenly stopped working.
When I put the motor out of the device, it ran sometimes. But not always. Like a loose contact.
But one thing is certain, it is not the supply lines, they also have power when the motor is not running. I cleaned the contact surfaces of the anchor and the coals with a bath lime cleaner with sulfamic acid and then solvent, and tried again. Same as before. I can't say whether the "fire" is stronger now. But it seems very strong compared to the Wikipedia video.
Is the engine over and need to be replaced? Because a replacement anchor (if it were) is probably not available for purchase.
If I make the effort to pull the sheet of the fan chamber down, I could remove the anchor.
If I knew where I could get a replacement engine ...
Also used. For example, with the names of other devices that contain this motor.
The idea of the 180 test is that you cover the same wire length each time, hence the need to choose consistent pairs of commutator contacts. Any variation around that test is an indication there may be internal shorts and would require either the armature to be replaced or serviced/rewired (specialised work).
Wonderful lesson about Broken Electric Motor? HOW TO Test If A Motor Armature With Commutator Is Damaged
what are those cuts/knicks?? are they suppose to be there??
Sure, those slots are made to perfectly balance the commutator
@@TheLabOtomy I mean on the stacks (the chunks missing on the grey/silver pieces) not the commutator.. sorry if
Yes, sorry, that is what I meant, those slots are made to perfectly balance the "armature: on a car you add small weights to balance a turning wheel, here since you cannot add anything, you shave off (well the machine does) the unbalanced weights until the armature spins without any wobbles.
How to fix it, would be a cool follow up.
Great video, nice clear instructions👍👌👍👌
Thanks
My multimeter indicates 0.4 ohm resistance between probes and between commutator segments, so resistance cant drop more.
How should i know if there is short between coils?
Best video on this topic. And a nice disclaimer. My field is black and has almost no insulation left. The armature has one suspicious coil. All of them are 0.3 to 0.5 but one is 0.6 , could it be normal or could this even be the reason why the field overheated? I dont know nothing obout the provious use of the mashine. It's a 15yr old dewalt but the blade was pretty dull.
So, a possible scenario in your case could have been:
1) Blade is dull, which causes
2) Motor to have to work harder, which causes
3) Motor to pull more amps, which causes
4) Armature coil to heat up beyond normal, which causes
5) Damage to the internal wiring (resulting in resistance discrepancy within the machine coils, 0.3 to 0.6 is a 100% variation which is real source of concern) and degradation to the insulation material (burning through and truning black)
6) Which causes the motor perceiving a loss of power to go back to 3) for a ultimate catastrophic failure
The Cause and effect theory at its best!
@@TheLabOtomy I could not have explained that better. Got an old dremel here that's got the same variance. I just happen to have some rolls of magnet wire that's just a little thicker than what's on it now. Time to rewind the armature and field core. Why would I do this? Because I can!! And just a little payback for pissing me off and failing when I needed it most! And from what I understand this particular model is known for this failure, and I am surprised that with this being a flex shaft only model they would have used a better quality wire and cooling fan!
In any case, Thank you for this informative video👊
hi
i replaced the brushes yet still sparking... the speed quite norrmal.. thank you.
Probably caused by dirty commutator bars. Use 800 grit sand paper on the commutator bars. When using sand paper, turn armature in one continous direction, not backwards/forwards is always best, 👍🏻👌🏼
If dc motor you can retard the timing as ive had brand new hobby motor sparking like hell and running extremely hot but after lifting the endbell tabs rotating anti clockwise to drop rpm the motor worked like it should!
What's a healthy resistance and what's a bad resistance?
There is no good or bad resistance (number of winding loops, winding design & patterns, motor sizes, winding wire gauges can all vary), it is all about being balanced across all segments so that the electromagnetic forces exercised are consistent to ensure a smooth rotation.
@@TheLabOtomy If the laminate comming on wire is damaged then would itbe possible for a number of windings to be shorted to it's neighbouring windings?
That is possible, the tests in the video can then show you a path imbalance
Is there a standard that document this test?
Not aware of one
what would cause an impact drill to continue spinning a few seconds after letting go of trigger? Bad trigger switch? Any ideas? btw this was a great vid
Is it
1) Still running at full speed and then slowing down or
2) Taking lots of time to reach full stop (slow slow down)?
The LabOtomy. #1 it works perfect besides taking a while to slow down. It just started doing this
So any ideas? The LabOtomy
Hm, I would indeed check on the switch first. Maybe it still causes current leakage upon trigger release
Electric brake faulty?
Any experience with a starter that engages but seems to not have enough power to actually move the engine?
Already checked for a bad ground, and all connections related to the starter and solenoid.
Verified there is no weak connections.
Solenoid contacts switch as designed. Brand new battery 2 days old. 2nd battery by the way.
Lights dim big time as the starter engages then stops, as if the engine is seized.
Ran fine the day before this issue arrived. lol Woke up to leave and discovered this problem.
I have not removed the starter yet. But I do suspect possible armature burn and/or brush damage.
Just not sure if one could cause such a MASSIVE power draw like this while never turning more than what seems to be an inch or two at most.
Could I be experiencing a less common commutator-armature stack short?
This is where a growler could come in handy
Well, that is now on the top of the list of "toys" for the garage. lol
Thank you for the response!!
Well, starter removal it is now. Worse case, I find out the problem is not with the starter.
Someone had mentioned a "dry" cylinder. Oil drained from the cylinder walls as it cooled, which caused one or more pistons to stick to the cylinder walls.
Any knowledge in that area? Before I start spraying lube into to cylinders anyway. lol
(oil light never came on, but I found I was abnormally low on oil.) NEVER heard any ticking or noise from the engine at any point. No shudders or lunges. Just smooth running one day, and no movement the next.
The Duder Cant happen. Never. Only if motor is outside, apart and on rain so it will rust.
busilica123
My thoughts on the engine as well.
Someone mentioned possible head warping as it cooled off. Others say the pistons swelled, which I know to be incorrect.
One thing is certain, I can not get the engine to rotate even when trying to push it using all gears.
I get the rear tire sliding only. Granted, I am not on the bike while trying to "push start" it.
Perhaps there needs to be weight on the bike to prevent the tire from sliding.
I have never had this happen before. And that includes my fist bike. (I was horrible with maintenance back then) It overheated a few times but never "seized" like this.
This bike has been babied. It is almost a sacrilege for me to own this bike, as I never even come close to using it's full potential. Just wish I knew why it started fine that morning, but the next morning, nothing.
And it is for sure the starter draining the system. I removed the starter from the circuit and hit the button. The fuel pump and all lights ran as normal.
Now I am praying there is a bolt inside the crank case so I can try to rock the engine loose. (If seizure is my issue)
could be short circuit or worn brushes, or even magnets breaking up and stopping rotation, i have experienced all of these, plus ingress of water can do this and create shorts in the electrical components. hope this helps. may the force be with you
Burn glaze on commutator copper and loud high pitch whine indicate overheating damage requiring rewinding and replacing the commutator?
How are the ball bearings looking? They can also be a source of strange sounds
hola cual es la resistencia que tiene que tener como minimo gracias
tengo entendido que no deben variar entre ellas, ice el video que el valor es irrelevante pero que deben ser similares
@@llamadeudun8291 ya ok
Serious tune what's the name of it?. Great explanatory video ☺️ saved it there
See the video description
I have several broken motors, and I find this video instructional because at least I can tell for certain that the motor is irreparable, (something that I already well figured out, as the vacuum cleaner does not clean and the hair dryer does not move air).
The video is very well done (artistic, indeed), and I've been hoping it could give me a hint on how to fix the coils by the bottom stack, but I don't think this is feasible with my limited capacities.
Like an egg and myself, my coils and brain are fried, it seems...
Nevertheless, the little funnies help me shed off the tears of what is now just a lump of metal...
Next, LabOtomy, sir, would you kindly show us how to actually *fix* the f'in thing?
Much appreciated,
D.P.
Thanks for the input, will think about it
At least a comment as to is it worth repairing. For most it isn't but some of us like that challenge. Why not....
@@ericsnyder3689 Excellent attitude!
Hi,ive taken the brushes out of my washing machine and moved the motor to the bench,the armature only moves about 5 mm to the left and to the right,and it cant move either way any more,any help please what may be wrong,
Busted bearings?
@@TheLabOtomy Thank you i found that out i hour later,but thanks anyway
Cool! Good luck with the repair!
Mine gave me 40ohm is it good or bad the wires look darker in color and fuse keep blowing
I could be wrong but to me, fuse blowing would indicate an issue with another section of the machine, like damaged wiring or a blown decoupling capacitor
@@TheLabOtomy the motor is for hand blender dc 220v the fuse doesn't blow when motor disconnected but when i connect motor and turn it on motor runs for 3 seconds then spikes and blow the fuse
Thanks for the super informative video :) , i have a Ryobi circular saw which lost about 80% of its power on me while cutting a piece of wood and everytime i use press the button to power it loads of sparks come out of between the brushes and the commutator bar,( the brushes have loads left on them ) so after watching this video i dismantled it and did the above tests and it passed on them all except on test no.2 where all my readings were 0.2 between each adjacent commutator bar EXCEPT one reading which was 2.3 instead of the usual 0.2 , so i take it this means i either need a new armature or scrap the saw ??
Hm, sparks but brushed big enough, 80% power of power loss and a 10 fold variation on bar-to-bar resistance test, seems we are getting all the signals of an armature coil saying "I shall live no more"
The LabOtomy OK thanks this is what I thought :(
Boss ngawa kaba ng old cercolar saw 100 volts
THANKS FOR YOUR SHARING SIR
Most welcome
May i add, your 3rd Test should also been done on Meg Ohm scale, reading should be higher than 1 megohm. Don't touch the probe ends as you will false readings
its a good video, thank you
Thanks Joseph
can u still repair it ?
I can not, but specialised electro shops do
Could you repair such a motor? And how?
Specialist work I'm afraid, some shops are specialised in electro motor reconditioning
Commutator can be arranged for four pole dc motor 12v. Please
Great tutorial, easy to learn..... thanks.
Welcome! Thanks for the feedback
i have a small electric motor on a child toy peg pelegro polaris. one motor is fine, the other does not have power. Took them off the gear mechanism, both turn, but one stops as soon as power is disconnected, and the other spins freely. no mechanical resistance. lube does not help. i took apart the the bad one, one coil is darker, obviously overheating. but not shortened. i measured the resistivity of all 3 coils, they start at 3-4 ohmes, then quickly reduce to 0.8 ohm. makes sense. Any idea, what is wrong with this motor? I bought a replacement, but this is my curiosity tickling me.
Dark is a bad sign, heat can cause isolation material to internally fail and the coil to propose a shorter electric path (implying a different magnetic field is generated that may longer cause the motor to improperly turn)
@@TheLabOtomy thats what i thought, but the conductivity of the 3 coils is the same. unless the shortage is between dark coil and armature
Hi.. i have a craftsmsn router keeps turning off due to sparks..i took apart and filed the commutator good on a lathe and then i flattened the brushes good and now it works a bit better but powers off at high rpm setting...sparks...anyone have any suggestions..brushes are about 1/2 in long
Dziękuję bardzo, skorzystałem!!!
Hola buenas tardes .. me recomiendas una armadura nueva o reconstruida .. unos me dicen que es lo mismo.. que me recomiendas tu
Nice info, thanks
These are men I wanted to work in our large mechanic/engineering/electrical and panel beating workshop. Men with brains I mean.
I wish I knew those guys
Thx for this video!
Welcome
Excellent explanation....congratulation!
Thanks Domenico
Nice,
I just made a video how to repair rusty angle grinder with broken with explanation because i read the comments of this video.
Thanks.
Hi Sir,
need your help regarding "Drop In Resistance" & "Resistance Spike", what this mean..?
I'm from Malaysia, like to learn about service & repair as you do.. :-)
Measured resistance should remain about the same: if it varies too much (goes down or up too much), there may be an issue with the communicator coils
uh-huh..hmmm..ok & tq sir...
So what is the conclusion? What does one do next? Must I rewind or else scrap?
Correct, rewind or scrap (or find replacement)
Thanks>>>>Subscribed!!!
Can anyone tell me why is there continuity between the comutator segments? Why are motors built this way? I thought comutators were suppose to separate the current, sending it through a different coil every time the brushes jump to the next segment?
I understand why the segments are connected directly opposite each other, just not right next to each other.
Sangat membantu , terimakasih infonya