# Help Needed Wiring In Power Feed On 1964 Bridgeport J Head Table Feed



## Mutt (Sep 21, 2016)

Bought a 1964 Bridgeport J head mill complete with table power feed, vise and super spacer rotary table for a $g. The standard table power feed isn't wired up. Can some one help me connect the wires? Motor is stock 1/8 hp 220v 3 ph.  
 3 leads coming from motor, no tracers or markings on these black wires. A 4 lead wire coming out of the main breaker box / reset  on rear of mill (standard 4 wire 3 ph red/black/white/green)
Last pic on left is the 3 leads from the motor, last right is the 4 lead cable coming from the breaker box on back of the mill


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## JimDawson (Sep 21, 2016)

I think you can safely assume that the 3 motor leads are connected to a motor starter in the panel.  The toggle switch would control the motor starter.

A picture of the inside of the control box would be helpful.

Do you have 3 phase power in your shop?


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## Mutt (Sep 21, 2016)

I have a static 3 phase converter hooked up.  Mill runs forwards and reverse.  The 3 black leads come straight out the side of the
electric motor on the power feed itself. The 4 lead cable comes out of a "reset" box on back of the mill. Looks factory to me. Here's some other pics The red and black wires were hooked up to the on/off switch when I got it.


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## JimDawson (Sep 21, 2016)

Yeah,...... that doesn't look right.  

The Green wire *should* be Ground, the Black, Red, and White wires should connect to the motor wires.  I would expect the switch to have 6 terminal screws, one pair for each of the 3 hot legs, one side to power and the other side to the motor wires.  Maybe the original switch was replaced by someone who was less than skilled in the art.  Theoretically you could use a Double Pole switch to turn a small 3 phase motor on and off, and just leave one leg connected, but it would leave one leg hot all the time, not a safe condition IMHO.

You need to take a look at the other end of that cord to see what it's wired to.


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## Mutt (Sep 22, 2016)

Ok, here's the motor controller
right side looking at it has the 4 wire lead from the converter, green ground, black/white/red to terminals on right side

left side has the  4 wires hooked to the left side terminals and the green to ground, also the 3 wires to the  power feed and the green to ground. All 3 leads to the power feed read 125v each, green reads ground


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## JimDawson (Sep 22, 2016)

I see what appears to be a motor starter in there, does that connect to the spindle motor also?


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## Mutt (Sep 22, 2016)

Yes,  spindle wires run from the switch's left side up to the drum switch on the top of the mill head


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## JimDawson (Sep 22, 2016)

I can't see enough of the box on the back of the mill to figure out exactly what it is.  It may be just an overload and switch for the motors.  There does not seem to be any way of operating a motor starter.

Bottom line is that the 3 feed motor wires should connect to the Black, White, and Red wires, preferably through a switch. Green should be connected to the motor frame.

Given that you are using a static phase converter to run the spindle and if you want to run the power feed without the spindle running, I would concider a small VFD to run the power feed motor.  Something like this one:

https://www.automationdirect.com/ad...l)/GS1_Drive_Units_(120_-z-_230_VAC)/GS1-10P2

Because if the power feed motor is started on the static phase converter without the spindle running the spindle may not start because the static phase converter has already dropped out.


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