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3 Phase motor connections.

3 Phase motor connections.

3 Phase motor connections.

(OP)
i need to connect up a 3 phase motor. my question is; the  main cable from the motor has 6 smaller cables in it (1-6) & a earth. i just need someone to remind me how i connect up 6 cables to the panel when only 3 connections are advaiable (red, yellow, blue) from what i can remember you need to use your multi-meter and test across the 6 cables so that you have 3 pairs that are not connected (ohms is 0 or meter does not bleep) am i right in thinking this???
thanks for your help.
alex

RE: 3 Phase motor connections.

(OP)
dint really answer my question :( its a standard uk 3 phase motor with 6 wires and a earth but i need to connect these 6 wires to 3 connections in the panel (red Yellow Blue) just need to know how you test the 6 motor wires to get your 3 pairs to connect tp the red yello & blue in the panel.
cheers
alex

RE: 3 Phase motor connections.

Are u connecting in star or delta, that would also determine how to wire up your six leads from the motor windingg before connecting up your 3-phase supply to the connection.Since u said only 3 phase , 6 wires, i guess you are not connecting for dual speed or dual voltage

RE: 3 Phase motor connections.

Alex,

Have another look at the linked document. If the core numbers are 1-6 then it is probably a US motor because those aren't standard British markings. The second page shows a six lead NEMA motor with core numbering 1-6 and how to pair them up. There are two options: delta or star connection which depends on how the motor was designed. It could be designed for 240V delta / 415V star connection or 415V delta / 690V star. If there is a nameplate can you post a photo of it?
 

----------------------------------
  
If we learn from our mistakes I'm getting a great education!

RE: 3 Phase motor connections.

A 6 lead NEMA motor may be a part winding start motor.
A part winding start motor will have continuity between two groups of three wires.
A star delta motor will have continuity between three groups of two motors.
I have seen two numbering schemes for part winding start motors:
123-678, and 123-789. Be sure to determine the difference between sixes and nines. Reading a six for a nine or vice versa will result in the second set of windings coming in out of phase with the first set.
(Don't ask me how I know)

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: 3 Phase motor connections.

What is the voltage on the name plate.?

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