# 3 phase wiring colors



## Jmanb13 (Jan 16, 2017)

I have a 1946 Leblond Lathe with a 3 phase motor. The wiring on the motor does not have the newer color codes to indicate L1, L2, and L3. On this motor all 3 are black.

Before I start adding external switches etc to tie into the VFD, I would like to get it up and running just the VFD to make sure the motor is still good. In my understanding of 3 phase, I should be able to just hook up the 3 wires to T1, T2, T3 and it doesn't really matter on the order. Worst case is that the motor might run backwards instead of forwards, and if so I would just swap 2 of the wires.

Is my understanding correct?


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## JimDawson (Jan 16, 2017)

Yup, That's how it works 

Having said that, make sure the motor is wired for the correct voltage.  Most common 3 phase motors are 9 wire, dual voltage, in the case of older motors they would be labeled 220/440.  The wiring diagram should be on the motor data plate or inside the connection box.

I would expect the motor wires to be numbered 1 through 9


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## Jmanb13 (Jan 16, 2017)

Here is the data plate on the motor. 220/440. I have not opened up the connection box on the motor itself, it is not exactly in an easy to reach location, I might have to take the whole motor off to get to it.


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## JimDawson (Jan 16, 2017)

Sorry, but the only way you can determine how the motor is wired is to look at the wiring in the connection box.

If it wired for low voltage (220) and it's a standard 9 wire motor then T1 is connected to 1-7, T2 is connected to 2-8, and T3 is connected to 3-9, and 4-5-6 are connected together.

If it's wired for high voltage (440), then T1 is connected to 1, T2 is connected to 2, T3 is connected to 3, and the other wire connections are 4-7, 5-8, 6-9.


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## Jmanb13 (Jan 16, 2017)

Based on your information if there is 4 bundles its 220v, and 6 bundles would be 440?

Looks like I have 4 total bundles (220v) in the connection box. Red Yellow and Blue are the wires coming from the power source.

So it looks like I just wire up 1 2 and 3 to my VFD with my 220v single phase input.


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## JimDawson (Jan 16, 2017)

Yup, that looks like a 9 wire motor wired for low voltage.


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## Jmanb13 (Jan 16, 2017)

JimDawson said:


> Yup, that looks like a 9 wire motor wired for low voltage.



Thanks so much for the help!


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## JimDawson (Jan 16, 2017)

My pleasure!


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