Induction motor, single phase, no capacitor to start needed.

[dish125db]

sounds like the starting phase is only working without the cap......

[coldarc]

ac motors works without capacitors. the only advantage with capacitors

is that there is no need for hand crank start and that they give out more mechanical power than the currents supplied by the input. the capacitor is generating extra power

for free. this is because the magnetic field is out of phase between rotor and stator.

the capacitor generate extra energy by increasing the phase differential between rotor and stator.

[ososordo]

el motor monofasico tiene 2 clases de bobina 1) TRABAJO: que es la que hace toda la potencia .- 2) ARRANQUE: es la que solo hace el primer giro de ayuda , ya sea izquierda o derecha .- el tema es que cuando se deja funcionando sin capacitor , la bobina de arranque se quema , ya que el bobinado del ARRANQUE se hace con menos vueltas que la de TRABAJO

[isovolt1]

you can see a better replacement at web page isovolt

[domyaska]

grazieee ..thanks a lot!! from italy

[u5ernam3unavailabl3]

The RL starter circuit created by using the wire will create a smaller phase angle of the magnetic field between the starter and main windings, and hence lesser torque which may cause the motor not to start when loaded as slandimore said.

[Arkthurius]

Right. One other very important thing people has not mentioned, is that in the case of permanent capacitor motors, the circuit with the capacitor not only needs to be properly shifted, but permanently connected. The capacitor circuit provides electromagnetic energy to the rotor, just like primary winding in a transf passes it to the secondary. Remember IndMot are "rotary transformers". I admit I did not thought about it when I recorded the clip. It was all about starting it without the cap.

[exp32s]

Dear Arkthurius

Thank you so so much for all your comprehensive videos on single-phase AC motor and your explanations. Your demonstration is clear. They reinforce my understanding of the operation of AC motor.

i would like to let you know i am very grateful for your efforts to upload those helpful videos : )

With appreciations

[slandimore]

i agree i have fitted and fault found on the following motor control systems single phase cap start single phase cap start cap run etc 3 phase star delta 7.5kw to 320kw 3 phase direct on line 3 phase inverter controlled 3 phase soft start 3 phase multi speed tapped windings 3 phase multi speed duel wound 3 phase resistance start single phase series parrell 480v series parrell so any body got any questions i would be more than happy to answer then if i can....

[CATA20034]

It has a bobin on the rotor , like dc motors aka washing machine motors ....

[osxdude]

lol what band was playing

[slandimore]

all single phase motors need a capacitor to start either left in momentory and then disconnected via a centrifugal switch or left in circuit. it is quite possible the this induction motor is able to start without a capacitor but it has no load on the shaft and by not having the cap disconnected you do not achive a full phase shife between the start and run windings thus not getting up to full speed.

[Arkthurius]

Good point. With load on the shaft the motor might not have enough power to start.

Electric motors are very interesting.

I have learnt lot of things from the comments of the people.

Thanks for posting.

[slandimore]

thanks for the reply....... just to add the capacitor on a single phase motor creates a phase shift of about 90 degrees between the start and run windings. on a 3 phase motor the is an exsisting phase shift of 120 degrees between phases thus all three adding up to 360 degrees and creating a rotation. this is not present on single phase motors. there are so many more types ie cap start cap run, series parallel, duel wound muilti speed, 480v series parallel, inverter driven, or soft start

[x65535x]

Notice how the motor never reached full rpm. You can hear how it was being underdriven. I would say electrical engineers and mechanical engineers that designed the motors to run with a capacitor surely new what was best.

[nightsoul2003]

Like he says at the top of the description "READ". He was just demonstrating that it is possible to start without the capacitor.

[Arkthurius]

Yes, in all my history of college study I never came up with a single phase induction motor unable to start when its capacitor was removed. When I removed the one from this and saw it could start it really got my attention. I really posted this video as a curiosity because of that, I never thought it would reach this amount of views. There arent really many videos on induction motors, not even in elementary level on youtube. Thanks very much for posting.

[Arkthurius]

Right, by removing the capacitor it turned at a lower speed. You said that engineers designed wrok well and that is also true. That white capacitor is the one the motor brought from factory, which is 20 microfarads. I ran it with a 32 microF one and it ran faster though. Thanks for posting.

[saibabatheboss]

cool video dude,,,,,,great work

[garumvhino]

of course a split phase motor doesnt need a starting cap... but they cant replace the cap-start bec. they hav a high starting torque than the split phase. their purpose is not the same..

[DarkLotus42000]

thats a start capacitor, starts are always plastic coated, run capacitors are always aluminum coated brass or titanium

[grunthunt]

you speak shit

[Arkthurius]

I am sorry dude. In this clip you can see two capacitors, one is plastic covered and the other is metal covered. Both are aluminum alectrolytic SH (self-healing) capacitors. These both are used for permanent running. Capacitors are chosen by their design which makes them suitable for different porpuses (permanent, start, PF correction). Depending it is electrolytic, mica, ceramic, or polymer it is more suitable for some porpouses. External color or material is not a key factor. =)

[statictruth]

ahhh, inductive reactance...

[ericksonlk]

I saw your video and that was great as I was searching how to fix my washing machine. It's working now (almost)

Thanks

[Latias82]

sounded awful without the cap!

[Swanny383]

It is called single phasing the motor, You will end up burning one of the windings, current goes though the roof, Just look at the wire arc, You are basicly "stalling" the motor, The cap gives it a "kick" then passes voltage onto the other windings. alowing it to spool up, you can run a 3 phase motor off of two phases, but your power will down 1/3, and you will need to use a cap to "kick" on the leg you are not using, or spin it up some other way then that "leg" will be open. (no current)

[Arkthurius]

All I knew was that the capacitor created a phase shift on one of the two legs, so they "appear" to be 90 degrees shifted, behaving like old original two phase motors.

[Arkthurius]

I had not read well what you wrote. I did not know single phasing could happen on a single phase motor like this. I had heard of it only on 3-phase motors.

[butkatrello]

You let that sucker run without the capacitor for a while, and see if it does'nt burn up that motor. It sounded rough without it

[Arkthurius]

Actually the amperage without the capacitor does not increase much, at least in this motor, but that is with no load. Dont know with load. My main atraction of this motor is that without the starting cap, the phase shift of the split phase is enough to run. All motors i had tried before stuck at starting when i removed the cap.

[Arkthurius]

I've modeled it but honestly haven't had the chance to do it because of lack of material. A 3-phase has its phases shifted 120°, and a single phase motor works by making the motor "think" it has 2, when all it has is 2 windings in parallel one of them with a capacitor to shift 1 phase 90°, then working as if it had the old 2 phase system. You need to shift each winding 120° either with capacitors or inductors. The point is the phase shift. My problem was getting a device to graph phase shift.

[turboslag]

Is it possible to run a 3 phase motor from a single phase supply with the motor making the same or near to the same power , if so how please ?

[tommyjay83]

Not at all. If you have a 230v single phase power supply you can buy either a Toshiba VF-S11 or VF-NC1 variable frequency drive. You can single phase the input of the drive and get three phase power out of it to feed your motor. Just de-rate the VFD by half (ie. powering a 5HP motor, use a 10HP VFD)

[zeropointfuel]

the capacitor is to help start the motor under load

[Arkthurius]

Right, that is acutally true only for capacitor start motors which autumatically disconnect after the start. On permanent capacitor motors the capacitor is not only to help the start, but also make the motor work on its nominal power.

[iceman3583]

ok but there is more magnetic noise without capacitor

[Arkthurius]

Good point. I have never actually seen that comment on any text book, and I have not analized the thing on a signal processor. If we remove the auxiliary winding would the noise still be there? I think thing would change a little because without the auxiliary winding the would not be induced voltage on that open circuit. I will try to see resulting signal...

[totalacedude]

all you are doing is powering up the start coil perminatly and not allowing it to be out of phase to aid it spin! ull prob burn out the coil soon.. but hey its something to do :op

[Arkthurius]

yup, the right thing i should do is to disconect the green cable to open the auxiliary winding so the motor runs only with the work one, practically just like cetrifugal switches work, what was interesting to me here, was that this was the first motor i had seen that even with no capacitor had torque enough to turn only using the little phase shift caused by the coil itself. The other motor on my other clip can't do that.

[sirmikeydotcom]

Half the speed, if you look closely

[Arkthurius]

Yep, I actually mention it on the clip description, I havent actually analyzed the circuit with a signal analyzer to see how precise the capacitor works and what phase shift it has without it.

[osmundsenistheman]

where/how can i get one/ make one?

[Arkthurius]

This motor is just a 1/2 HP peripherical water pump motor, it cost me about 40USD. I bought it for my educational porpouses. It has lasted long though. Any shop of household artifacts should sell this stuff. Buy the motor alone better, not a pump, i bought the pump because it was on discount, I only needed the motor. It really helps to understand the basics and learn the principals of induction motor mechanics.

[fdoca]

anyone know that, is possible convert a regular motor to a permanent magnet motor? I mean, like a pulse motor, Thanks

[cojobo34]

wow, u shore make me feal rilly dum... and i alwayes kinda thot i was intellergent to.lol,j/k

Good job man, pretty cool display.

[diazgabs]

how can i make something like it?? for a physics project? or similar??

[Arkthurius]

As I said on the description of the video, my intention was to show what the capacitor does in permanent capacitor induction motor. I am preparing a new clip more complete about this.