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Electric Motors/Three phase 12 Lead Motor winding connection


I Have A Motor With 12 Leads, Labelled W1, W1, W2, W2 U1, U1, U2, U2, V1, V1, V2, V2,
How Can I Connect It For 440V Connection.

IEC 12 LEAD THREE PHASE Electric motor connection diagram

Kevin,   I forgot another important fact,  you have double W1s  so on,   so I am pretty sure you really have a 6 lead motor,   they use smaller wire for leads,  so it is not such a pain to wrestle around    but if you have a VOM  ohmeter whatever,    a great help would be to take the ohm meter and tell me what goes with what,      in other words  is W1 a double lead?

They make it difficult but that is why you have a very good question and a weird motor connection          but we WILL FIGURE IT OUT

Kevin this a tricky one  Some Toshiba's and Lincoln Brand motors use all three phases connected externally,  in parallel for 440 volts  most of the time the higher voltage is WYE  . That really jacks people up.  It probably is at least 25 HP and likely larger.

That is the one caveat I cannot answer,     is the full external Delta connection designed to be 440/460/480   [HIGH VOLTAGE].

This jacks up many people and why they do it  I don't know.

You got ANYTHING on that motor?  Nameplate? Manual? Inside Connection box? Can you send it to me? [Private e-mail] photo of nameplate,  connection plate,   anything so I can try and figure out if this is a full parallel delta 440 connection.

I can normally figure it out,  by looking at the size of the leads,   attach an amp rating to an individual lead     then add up the amount of current  compared to the name plate data    

This is IEC motor lead marking     BUT THIS ODD Toshiba, Lincoln and a few others throw a monkey wrench into things and IT GETS SO CONFUSING       so I need to check it out for you

Specifically   the standard connection for just what you have is found here :

They just jack around with these 12 lead motors   so I really want to double check what you have   I can figure it out,  with a little more info,      but you can use this for now,    

Here is the difference    standard 12 lead you will have two motor leads per line

Toshiba 12 lead you will have 4 motor leads per line,     SEE THE DIFFERENCE ?

I can't tell you yet which way it is internally wound,    but I can  gotta have more specifics on YOUR motor,       

I don't make this crap up,   but people get all balled up by NOT KNOWING IT IS EVEN POSSIBLE   so for now,  here is the standard IEC 12 lead connection diagram  

MOST ARE STANDARD        MOST         let me know if you have ANYTHING ELSE   on that motor  photo of nameplate   ANYTHING  

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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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