12 wires?
12 wires?
(OP)
i am an english electrician and read a lot on here about 12 wire motors i have only seen 6 wire over here ie 3 coils can someone explain
cheers
cheers
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RE: 12 wires?
Check out this web site you may find it helpfull.
Chuck
http://www.reliance.com/mtr/mtrthrmn.htm
RE: 12 wires?
Wecome to the forum, nice to see another Brit!
What our American friends like to do is bring a lead off some of the coil ends internaly, then make some or all, depending on the winding design, of the inter-coil connections inside the terminal box. On the otherhand we in Europe generaly make all the inter-coil connections internaly and bring just six leads out of the winding to allow for star-delta starting, or three leads out if the winding is suitable only for DOL starting with the star or delta connection made internaly. The six leads are the start and finish of each of the three, phase circuits and each circuit may be made up off several coil groups, not just one. Machines with 12 leads out are very rare in the UK and you are unlikely to come across one unless you work with machinery imported from the States or Canada. They tend to burn out relatively quickly because of the diffences in supply voltage and frequency but the winding design can be modified slightly by making alterations to the cross sectional area of the wire and the number of turns in each coil to allow for these differences when the motor is rewound.
RE: 12 wires?
Making the motor three phase means you now take the two groups multiplied by the two leads multiplied by three phases which now gives you a total of twelve leads!
RE: 12 wires?
RE: 12 wires?
speed control -two fixing speed with three phase motor or 6 fixing speed with one phase. They have the old motors with meny poles and coil.
RE: 12 wires?
I doubt anyone would commonly bring out leads for one pole separately from its opposite. I believe it is useless if it is connected incorrectly unless maybe you are wanting to make a consequent pole motor to run 1/2 speed.
Jim
RE: 12 wires?
The twelve wires minds the 3 Phase Squirrell cage Induction motor can work for two voltages, in america usually 460/230Volts and in europe 220/380 Volts.
This design is made with the prime objetive for the starting“s motor usually the motor can be started with star-Delta in both voltages,also you could start the motor in Part-Winding.NEMA-STANDARDS use Numbers to mark the wires from 1 to 12. In a Three Phase motor the wires in Phase a are labelled like 1-4-7-10, phase b: 2-5-8-11 and phase c: 3-6-9-12 in Europe the leads are labelled under IEC Standard and Phase a : U1-U2-U5-U6 Phase b: V1-V2-V5-V6 and Phace c: W1-W2-W5-W6. If you perform the right connection then the motor will run well.
Regards
PETRONILA