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Electric Motors/Single phase motor Kansas City Missouri


QUESTION: I have a 220v 8A 20uF cap start monophase induction motor out of a Zanussi washing machine that i would like to fit on a press drill.  The pod on the  motor has 5 coloured wires going to the 5 terminals as follows: 1. Dark Blue 2. Pink 3. Purple 4.Brown 5. Pale blue.  The resistance between them and resultant speeds when these two wires are connected to the mains are: 1 and 2 is 62 Ohm and runs slow, 1-3 44 slow, 1-4 56 slow, 1-55 53 slow, 2-3 66 slow, 2-4 50 slow, 2-5 76 very slow, 3-4 10  very fast 3-5 29 fast 4-5 22 fast.  So, can you tell me which two are for the capacitor and how to connect the rest?

ANSWER: Washing machine motors of any stripe are always a problem outside of the OEM washer with the OEM connections,      some leads are for instant reversing,   some have two dedicated cap leads, some you have one start on one side of the cap, and on the other a run with line,       as this is a permanent split capacitor motor,          I am guessing no diagram from the washer to try and translate from?

I will draw the winding out,  nice job of getting me the resistances    it might make sense when I get all the dots connected,        you seem to know a bit about motors,      I am curious as how you chose 1 and 3 as commons or at least a convention you stuck with,       is there any information that lead you to choosing  1  and  3  as always on line?

Got any idea how many speeds this thing had?

Typically  the run windings are the lower resistance windings,          and a single phase permanent split capacitor motor wires up like this,          

Line one run and one start   [common]          line to cap with a run,          other side of cap a start by itself,     to change speeds   most leave the line on the cap,  and swap the other run leads that go to line as a common,

long link to some generic PSC motor connections,  

I can find nothing on Zanussi   and not surprised,   a lot of that brand has a commutator type motor,   but there are some with PSC motors,        the only info in the US I could find was what I expected,   follow the wiring diagram of the machine to the controls,    

Most washer motors have an OEM oddball  terminal strip,  with no information on what is what,     1 through 5 are not NEMA or IEC  standard motor numbers,        

I am surprised you got rotation without the cap,    but I would bet on the SLOW connections if you give the shaft a spin in either direction before energizing,   it will run the direction you pre spun the shaft,      

It will take some time to draw out a connection with the leads and ohms and how they interface internally,      and then I may have only a guess,    

A sure fire way to know is to remover the end housing,  cut the wiring ties, and take a drawing off the motor windings,          but as far as this brand  I have nothing to tell me if one is a run or start or any other combination,        the fast connections are probably close to correct  as far as line    but where to insert the cap in there with the start winding is another problem,     

Let me draw it out, and hopefully it will make sense  so I can give you some options,  it is probably a two or three speed motor,  most are,   with five wires three speeds would be possible,     but how they connect internally is OEM  and getting that info from the manufacturer is probably not possible,          

If you have the washer,    then you have the best diagram   but it will take as explained   following the motor leads to the machine controls and then making the same type of swapping  externally   with some kind of drum switch,  or multipole center off toggle,     

Lets see what the drawing looks like  and see what we can discover from there,       any information    if somehow you found that 1 is line  and 3 is line   from the machine itself    I need to know that,      any tid bit of info will be a help,          

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QUESTION: Thanks Will for prompt answer.   Actually, I did not choose line 1 and 3 as the main inputs.  But since 3 and 4 gave the fastest rotation and 3 and 5 the second fastest then 3 might be important.   I should have also said that all combinations worked in both directions with a hand twist.  Also that all slow combinations made an electromagnetic growling noise.  Today I opened the pod and found that the internal wires are different colours and sizes to the wires going to the pod.   They are 1. yellow, 2. Green, 3 Blue, 4 White and 5 Brown.  All are surprisingly small except for the white one.
You asked about my method.  I made a matrix with 12345 horozontally and 12345 vertically then put the ohms in the boxes.   I think the washing machine had 3 speeds slow forward, slow backwards and fast forward.
Found a link on youtube to a similar motor that read "There's NO frequency controller! It's only depends which coils are connected! This motor has 5 coils! 2 for high speed, and 3 for low speed, and on low speed you can change rotation direction, that's reason why it has 3 coils for low speed. (
Hope that helps

ANSWER: You do very well at diagnostic information,     what the video meant was a large majority of new multi-speed motors are done by changing the incoming line frequency so there is basically one winding  and the line frequency is changed from 60 cycles and lowered for for slower speeds and raised for higher speeds,     

That is true not what you have,    the reason yours turns in both directions is because at least one start and one run  have to be on line     with the end of the start on the cap,   then the other line is on the cap  with a run lead,      

So when you used just two     there was no start,      so it could run in either direction  but not correctly,     speeds make sense    

Yes the low speed growling is due to having say a low speed run only on line,   the combinations  are   many obviously   

Yes the wire is small   pretty amazing,   

The white lead is larger     it could be common,   white is often used as common,   

we need common on line try white   then     a higher resistance lead from common on the cap [a start by itself]   then a lower resistance [run] lead on the other cap terminal with the other line,     so you can pick some lower and higher resistance coils and make notes how it operates  

it will take several hours to draw this out and I will get with winding foreman and we can look it over,          

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QUESTION: Ok Will.  Getting somewhere. L1 to 4 (fat white) L2 to Cap and 3, cap to 5 slef starts and runs fast right.  Swap 5 and 3: self starts and runs fast left.    Swap 5 with 1 and runs slow right.  Swap 5 with 2 and runs slow left.    I may have misleed you over the cap.  Closer inspection of the pod lid reads: 2 poli 2900 o/1 4A Cond. Carta 20uF 450v, 16  pole 320 0/1 1.4A Cond. Carta 20uF 200v.  Assuming that Poli is poles, o/1 is RPM and Cond. is condensor then Carta means run or start. As there is no sign of a centrifical switch that would shunt a starting cap, then maybe it has two run caps for the two speeds. what do you think?

You are getting somewhere,      it appears Fat white 4 is Common,      3 is a run winding lead,

and 5 is a start winding lead,       YOU DO know about electric motors,      very impressive,  

2 poli means it is a two pole motor,  at 2900 RPM  base speed,   and with it being 50 cycle  that would be about right for a two pole motor,      with a bit of slip,     and using a 20UF cap,  with a 450 volt rating which is by the way,   a min volt rating,  so a 600 volt cap would work,    but the 20 uf has to be pretty close     then we go to 16 pole     2, 4, 6, 8 [900 RPM], 10, 12  so on poles,  this would be a separate winding [run]   and maybe? a dual rated cap    what is odd,   is the 200 volt rating on the low,  probably drain,  or low low speed setting for delicate clothes,    

I don't believe I remember ever seeing a dual uf rated cap with two voltage ratings,  so it is not likely it was engineered to use two caps,          

Many condenser units have dual uf ratings,   one for the compressor and one for the fan,  but they are always a single voltage rated cap,      you would think after 30 plus years of this I would have seen a dual voltage cap,     and have not,        but will look up,

16 poles at 60 cycle US is 450 sync rpm,      at 50  375 RPM sync,      so it slips to 320  which makes sense,      

same as 2900 on the two pole winding      50 hertz is 3000 slipping to 2900 base sync   

NOW  here is a question,  the press probably has some sort of belted or geared transmission,  do you know what the drill states as a main speed or speeds for the motor?

Some presses  the more elaborate,  have two speed motors,  so the arbor speed can be adjusted to twice the amount of mechanical speed selections,      when you get down to a 300 RPM motor  compared to 2900    that is some real slow speeds for a drill,    if the gearing is like most,    and the higher speed also seems to be high for a typical press,   normally they are 1800 base  and often   1800/900  where it can be a one winding constant torque motor,       

So is the press going to be OK with a base speed motor of 2900 or 300.,?  It of course depends on what you will be drilling and how much you will use it for what,    worth checking into,   but I think you have the motor nearly correct,  with the cap being 20uf on both,  the only thing I don't understand is why the voltage rating difference?

I mean why use two caps?  Either needs 20uf,  the high speed cap if rated at 450 volts is going to be fine on 200 volts,      but where they get the 200 volts    not sure yet,      

But your 20UF  is enough or adequate to put the start and run out of phase properly for both speeds according to the plate,        must be some kind of tapped winding,       but at this point if you need both speeds I say the one cap will handle either,    as long as it is rated min  450 volt,          

The uf ratings tell me the caps are oil filled run caps,  BUT sometimes in washing machines,  the centrifugal switch is not in the motor,        sometimes on a second shaft external,  or even on an eccentric shaft      the motor doesn't care as long as the cap and start winding is opened at a certain speed,

o/1  could that be oil  ONE   ?   I have to read up on my IEC single phase motors,  and find this odd combination of things,    but you are close if not there,        I just dont see using two caps  if both windings need 20uf and the overall rating is 450 volts that voltage rating is going to cover both,       so I see no reason to have two caps,  

With the uf so low,   it is more likely we are looking at a PSC dual speed,   most dry cap  start capacitors are 200 uf   and up,       most PSC motors are down there in the single to double digit range of farads,        

So  I am waffling on the PSC motor,

the above link will say start windings are low voltage meaning the start is rated for a dual voltage motor at the lower voltage and tapped off the series connection,    so the start is always at the low voltage,    but this is SPEEDS        or I have seen motors where the low speed is a very short service factor,   and adds the multiple poles onto the higher  lesser pole winding     kind of acting like a dynamic brake winding,         

But in this case  I think we have two individual windings,    one cap,  of a high enough volt value     the voltage thing does throw me a bit,     they are sorta acting like it is a start winding,     with the low voltage rating of the cap,      so that flies in the face of two individual windings,    

Somehow the 16 poles has to see less than 200 volts, and it does not have two power supplies

I think you are there   change the speeds on the run on the cap,    should be just two speeds   no growling or hum   let me know  this is very interesting plus I very much appreciate and enjoy your knowledge and understanding of motors and power  

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Three phase/ AC DC single phase motors, controls, any problems or failures, motor installation, performance issues, connections. All other electric motors/gearboxes/apparatus. Specialty repair concerns, obsolete motors and solutions. Other mechanical or specialty equipment. See my profile under Home/electrical at this site


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