Thank you after watching other 7 videos your demonstration made it quite simple to understand some youtubers tend to overcomplicate it. I was looking at a schematic with a dc motor that had a brake that just shorted the terminals, my head couldn't work out how it was working you demo clear this up. thanks
I just had to trouble shoot why a motor on my airplane (used to raise and lower the landing gear) wasn't dynamic braking like it should. My mechanic tried to explain it to me, but your video was great. I get it now! Great job!
thank you! i finally was able to understand what dynamic braking in a diesel electric locomotive is! such a simple idea yet I always wondered why steam locomotives always have a diesel tag along for dynamic braking...
Thank you.. the best video that explains dynamic braking. I had some questions about locomotive dynamic braking and got the answers by reading the comments. thanks
+Bilawal Hassim Thanks for your pleasant comment. Locomotives actually drive their wheels with electric motors that can also act as generators. Even though the locomotive runs off of diesel power the diesel engine is used to drive a master electric generator to power all the electric drive motors to make the locomotive move. When the locomotive must brake these drive motors can be configured to act as generators. Power from these generators is routed to a resistor bank which loads down these generators and slows them down. When the generators are loaded down they begin transforming the kinetic energy of the locomotive into heat which slows the locomotive down. Dynamic braking is critical in this situation since it minimizes the need for mechanical brakes which greatly extends the life of the mechanical brakes which are only used to brake at slow speeds or keep the train from moving when it is stationary. I’ve included a link to a not-so-great video of someone explaining the concept. ua-cam.com/video/f-tnwlyOmNk/v-deo.html Regenerative braking is quickly replacing dynamic braking since it allows the braking energy to be captured and used to help run the locomotive.
+Dorian McIntire Thank you again for the further explanation. yes I watched that video but without any practical demonstration it is very difficult to understand. I'm a rail buff and interested in locomotives generally. so these days I'm researching about dynamic braking and came across your awesome video.
Very nice explanation...Thank you! Is there a way to adjust a dynamic brake so it does NOT stop the motor so quickly? I have a Dynamic Brake on a saw and it stops the motor so quickly, it loosens the arbor nut every time.
It is more difficult to stop an AC motor. To stop an AC motor you must apply a DC voltage to the windings. The process is known as DC injection braking. Applying a lower voltage will stop the motor less quickly than using a large DC voltage.
If you would have the motor connected to the battery, spinning, and then change the +/- connections while its still spinning, lets say its in a train and you want to stop it. So it has forward momentum, and you change the connections of either excitation or armature. Motor would slow down with momentum dependent on the current through its windings (whichever winding you control). Would armature then during that kind of braking be using electricity or producing it?
Break Man I think it would be using it, and it would be using a lot of it to stop the train quickly, and all the energy discipation would be on the motor which might overheat it. Thats probably why DC trains just switch armature to a resistor like you did here to slow down to near stop and use that energy up in a resistor instead of the motor. Downside is they cant do a full stop with only that method since it approaches 0rpm very gradually, they'd have to switch connections +/- to get it to a stop and disconnect voltage when it stops so it wouldnt start spinning in other direction. But I think they just use mechanical brakes for that last bit.
Break Man Yes most trains are diesel-electric and use dynamic braking to slow down and stop the trains. The electric motors that drive the train wheels can also become generators and energy from these motors is diverted into resistor banks that turn into heat. Newer trains are using regenerative braking in which braking energy is stored and reused to help start the train again.
Hi, thanks for your video. May I ask if the motor running in the high speed and apply dynamic braking instantly, will it damage the wiring since the resistance is too low?
That is not a problem since all you are really doing is changing the motor from a motor to a generator. When the change to a generator occurs the current generated is not much more than the stall current of the motor which must be tolerated by the motor when initially started.
If the DC motor can create a higher voltage than the battery while rotating it can charge the battery. A good example of how this can work is a hybrid automobile.
we men and some women have dynamic braking in our homes and don't even know it, power tools drills, if you were to hold the spinning part of a drill and apply a small amount of power and try to spin the drills head it is going to be hard to spin, release the power and the dynamic braking is gone. i forget to mention do NOT try it on your expensive drill it will damage it. talking from experience. and really nice video!!
Thanks for making an obviously complicated topic seem so simple. I need to deploy this knowledge to a pet project. I am building an automatic gate opener. My challenge is how to make the gate stop as it hits the limit switch, but the motor keeps going for seconds due to inertia (i guess). Should i just reverse the polarity to achieve an abrupt stop? How about the inertia, will it cause any damage to the motor internals? It's a 3hp dc motor, operated with 24v battery.
All you really need to do is load the motor down by shorting its leads together. If you want a slower stop load the motor by connecting a low value resistor to its leads.
Very good vid. Had a ? I have a 1 HP 110/220 ac motor. I believe it has a break on it. I have it connected to a flywheel (325 pounds ) for starting up to it's speed. I need to disconnect the internal brake so it slows down naturally how ever long it takes when power switched off . can this be done? again thanks for the vid.
Is the motor singel-phase or 3-phase. Whether it's a mechanical brake or electrical brake I should be possible to remove it. Electrical brakes for AC motors usually work by applying DC to the rotor.
+Dave Smith I got these Ametek motors from C&H years ago. They were originally designed as drive motors in large tape-drive assemblies but are now being sold as wind generators. Ebay has these for a better price. www.ebay.com/itm/Ametek-Motor-07980-80003-010997F6-40-V-D-C-Nominal-/301872669726 Any large, low RPM, DC motors will work well. Good luck.
Thanks for the quick reply Dorian. What interests me is the large gear that is easy to spin for generation. Do you have a url for C&H? I found many companies with that search.CheersDave
Most any DC gear motor with an output RPM between 15 rpm and 40 rpm will work fine. You must add a piece to the output shaft to allow you to turn the shaft with your hand. I have used a pair of vice grips on motor shafts of other gear motors to do this. The motor in the video was removed from a piece of equipment and worked well without having to add anything. www.amazon.com/dp/B01KTYOUBQ?psc=1
The motor used in the video was removed from equipment. However it is very similar to the following motor available on Amazon but without the gear used as a handle: www.amazon.com/LMioEtool-Torque-Reversible-Electric-Geared/dp/B07PYK78T5/ref=sr_1_2_sspa?crid=19SM58L62V9D&dchild=1&keywords=gear+motor&qid=1592291803&sprefix=gear+motor%2Caps%2C169&sr=8-2-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEySUhDMTNET1JQM0E2JmVuY3J5cHRlZElkPUEwMDM0NjQwM0pBOVdVRkJSRFUyMSZlbmNyeXB0ZWRBZElkPUEwNTc5NDczMldNVzFCTFZTMFdXOSZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=
All permanent magnet DC motors are also generators you should buy a pair of these with the same specifications although the exact specifications is not too important except you will want a big reduction in speed on the output shaft. Even cheap gear motors like the ones at the following link will work and they have a wheel you can fasten to the shaft to turn. www.amazon.com/ZJchao-Arduino-Plastic-Wheel-Motor/dp/B01934CLG4/ref=sr_1_15?ie=UTF8&qid=1495892447&sr=8-15&keywords=DC+gear+motor Have fun
Dorian; thank you for taking time to make these videos. Not only are you knowledgeable but also talented at conveying the information out to us. 😊
Thanks! Comments like this help keep me motivated.
Thank you after watching other 7 videos your demonstration made it quite simple to understand some youtubers tend to overcomplicate it. I was looking at a schematic with a dc motor that had a brake that just shorted the terminals, my head couldn't work out how it was working you demo clear this up. thanks
Just watched runaway train with Denzel Washington. Very helpful and informative. Thank you!
You are a genius...so well explained. absolutely love the magnet slowdown fall
I just had to trouble shoot why a motor on my airplane (used to raise and lower the landing gear) wasn't dynamic braking like it should. My mechanic tried to explain it to me, but your video was great. I get it now! Great job!
Watched two of your films so far and they are great. No doubt I'll be back to watch others soon. Nice clear explanations.
+DJ Walker Glad you liked the videos. Thanks for watching and commenting.
Unfortunately it was not introduced in physical-science class in high school. Oh dear.
Magnificent video.
Cheers from Indonesia
thank you! i finally was able to understand what dynamic braking in a diesel electric locomotive is! such a simple idea yet I always wondered why steam locomotives always have a diesel tag along for dynamic braking...
Thank you.. the best video that explains dynamic braking. I had some questions about locomotive dynamic braking and got the answers by reading the comments. thanks
+Bilawal Hassim Thanks for your pleasant comment.
Locomotives actually drive their wheels with electric motors that can also act as generators.
Even though the locomotive runs off of diesel power the diesel engine is used to drive a master electric generator to power all the electric drive motors to make the locomotive move. When the locomotive must brake these drive motors can be configured to act as generators.
Power from these generators is routed to a resistor bank which loads down these generators and slows them down.
When the generators are loaded down they begin transforming the kinetic energy of the locomotive into heat which slows the locomotive down.
Dynamic braking is critical in this situation since it minimizes the need for mechanical brakes which greatly extends the life of the mechanical brakes which are only used to brake at slow speeds or keep the train from moving when it is stationary.
I’ve included a link to a not-so-great video of someone explaining the concept.
ua-cam.com/video/f-tnwlyOmNk/v-deo.html
Regenerative braking is quickly replacing dynamic braking since it allows the braking energy to be captured and used to help run the locomotive.
+Dorian McIntire Thank you again for the further explanation. yes I watched that video but without any practical demonstration it is very difficult to understand. I'm a rail buff and interested in locomotives generally. so these days I'm researching about dynamic braking and came across your awesome video.
+Bilawal Hassim Glad you enjoyed the video. Sounds like I need to make another dynamic braking video as it applies to locomotives. Thanks.
Yes pleeeease :)
Make a video on regenerative braking of locomotive.
Very nice explanation...Thank you! Is there a way to adjust a dynamic brake so it does NOT stop the motor so quickly? I have a Dynamic Brake on a saw and it stops the motor so quickly, it loosens the arbor nut every time.
It is more difficult to stop an AC motor. To stop an AC motor you must apply a DC voltage to the windings. The process is known as DC injection braking. Applying a lower voltage will stop the motor less quickly than using a large DC voltage.
@@DorianMcIntire Thank you for your response. I wish I could send you a picture of the brake that I had rebuilt.
If you would have the motor connected to the battery, spinning, and then change the +/- connections while its still spinning, lets say its in a train and you want to stop it. So it has forward momentum, and you change the connections of either excitation or armature. Motor would slow down with momentum dependent on the current through its windings (whichever winding you control). Would armature then during that kind of braking be using electricity or producing it?
Break Man I think it would be using it, and it would be using a lot of it to stop the train quickly, and all the energy discipation would be on the motor which might overheat it. Thats probably why DC trains just switch armature to a resistor like you did here to slow down to near stop and use that energy up in a resistor instead of the motor. Downside is they cant do a full stop with only that method since it approaches 0rpm very gradually, they'd have to switch connections +/- to get it to a stop and disconnect voltage when it stops so it wouldnt start spinning in other direction. But I think they just use mechanical brakes for that last bit.
Break Man Yes most trains are diesel-electric and use dynamic braking to slow down and stop the trains. The electric motors that drive the train wheels can also become generators and energy from these motors is diverted into resistor banks that turn into heat. Newer trains are using regenerative braking in which braking energy is stored and reused to help start the train again.
Hi, thanks for your video. May I ask if the motor running in the high speed and apply dynamic braking instantly, will it damage the wiring since the resistance is too low?
That is not a problem since all you are really doing is changing the motor from a motor to a generator. When the change to a generator occurs the current generated is not much more than the stall current of the motor which must be tolerated by the motor when initially started.
@@DorianMcIntire Thank you for your explanation
Does it mean that any DC motor connected to a battery will charge it while being rotating?
If the DC motor can create a higher voltage than the battery while rotating it can charge the battery. A good example of how this can work is a hybrid automobile.
we men and some women have dynamic braking in our homes and don't even know it, power tools drills, if you were to hold the spinning part of a drill and apply a small amount of power and try to spin the drills head it is going to be hard to spin, release the power and the dynamic braking is gone. i forget to mention do NOT try it on your expensive drill it will damage it. talking from experience. and really nice video!!
+cdm1250uhf1 Good comparison. Thanks for watching and commenting.
Thanks for making an obviously complicated topic seem so simple. I need to deploy this knowledge to a pet project. I am building an automatic gate opener. My challenge is how to make the gate stop as it hits the limit switch, but the motor keeps going for seconds due to inertia (i guess). Should i just reverse the polarity to achieve an abrupt stop? How about the inertia, will it cause any damage to the motor internals? It's a 3hp dc motor, operated with 24v battery.
All you really need to do is load the motor down by shorting its leads together. If you want a slower stop load the motor by connecting a low value resistor to its leads.
@@DorianMcIntire Thanks
Very good vid. Had a ? I have a 1 HP 110/220 ac motor. I believe it has a break on it. I have it connected to a flywheel (325 pounds ) for starting up to it's speed. I need to disconnect the internal brake so it slows down naturally how ever long it takes when power switched off . can this be done? again thanks for the vid.
Is the motor singel-phase or 3-phase. Whether it's a mechanical brake or electrical brake I should be possible to remove it. Electrical brakes for AC motors usually work by applying DC to the rotor.
Thanks you very much its very good way to explain dynamic breaking.
sajid naseem You're welcome. I'm glad you found the video useful and really appreciate your comment. Thanks.
Dorian, this is a great demo. Where are you able to order the motor/generators?Cheers Dave
+Dave Smith I got these Ametek motors from C&H years ago. They were originally designed as drive motors in large tape-drive assemblies but are now being sold as wind generators.
Ebay has these for a better price.
www.ebay.com/itm/Ametek-Motor-07980-80003-010997F6-40-V-D-C-Nominal-/301872669726
Any large, low RPM, DC motors will work well. Good luck.
Thanks for the quick reply Dorian. What interests me is the large gear that is easy to spin for generation. Do you have a url for C&H? I found many companies with that search.CheersDave
which type of motor or generator did u use plz reply , specification about these like rpm etc
Most any DC gear motor with an output RPM between 15 rpm and 40 rpm will work fine. You must add a piece to the output shaft to allow you to turn the shaft with your hand. I have used a pair of vice grips on motor shafts of other gear motors to do this. The motor in the video was removed from a piece of equipment and worked well without having to add anything.
www.amazon.com/dp/B01KTYOUBQ?psc=1
Sir
Send me purchase link in this motor please
Please sir...
The motor used in the video was removed from equipment. However it is very similar to the following motor available on Amazon but without the gear used as a handle: www.amazon.com/LMioEtool-Torque-Reversible-Electric-Geared/dp/B07PYK78T5/ref=sr_1_2_sspa?crid=19SM58L62V9D&dchild=1&keywords=gear+motor&qid=1592291803&sprefix=gear+motor%2Caps%2C169&sr=8-2-spons&psc=1&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEySUhDMTNET1JQM0E2JmVuY3J5cHRlZElkPUEwMDM0NjQwM0pBOVdVRkJSRFUyMSZlbmNyeXB0ZWRBZElkPUEwNTc5NDczMldNVzFCTFZTMFdXOSZ3aWRnZXROYW1lPXNwX2F0ZiZhY3Rpb249Y2xpY2tSZWRpcmVjdCZkb05vdExvZ0NsaWNrPXRydWU=
@@DorianMcIntire
Thanks sir
link for purchase these motor n generator
All permanent magnet DC motors are also generators you should buy a pair of these with the same specifications although the exact specifications is not too important except you will want a big reduction in speed on the output shaft. Even cheap gear motors like the ones at the following link will work and they have a wheel you can fasten to the shaft to turn.
www.amazon.com/ZJchao-Arduino-Plastic-Wheel-Motor/dp/B01934CLG4/ref=sr_1_15?ie=UTF8&qid=1495892447&sr=8-15&keywords=DC+gear+motor
Have fun
thx bro
Lenz Law 5:40
Correct!
@@DorianMcIntire 😊
really nice
Superb
thanks so much i get it
That's what I like to hear. Thanks for commenting.
thank you so much