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Help! Need to wire up motor on mill to reverse

gavingear

Aluminum
Joined
Apr 24, 2008
Location
Cashmere, Washington
Hello everyone, first post here at practical machinist. Just finished wiring up the drum switch on my Logan lathe to reverse the spindle for threading with dies, and now I'm on to my milling machine- need to figure out if I can reverse the motor, and if so, how to wire it up so that power tapping is productive. (Currently I drive the tap down, loosen the collet, back out with tap handle). My plan is to buy a drum switch and wire it up so that I can reverse the motor from the drum switch.

Unfortunately, there's no color coding chart or anything on the motor (checked inside the wiring box, nothing there...) so I'll need to know:
1. Can this motor be reversed
2. How do I figure out which wires are which?

Here's the text from the motor:
Single phase induction motor, capacitor starting
Power: 1HP
Voltage: dual, 120/240VAC
RPM: 1723

Here's some pictures including the motor tag with non-color coded diagram:
http://gavingear.spaces.live.com/blog/cns!334AA2AFC5544E64!291.entry
 
If both ends of the start winding are brought out to the term box then you have to identify the two ends and essentially reverse them externally.
Or the two ends of the run winding can be swapped over.
One end of the start winding is connected to one capacitor connections, the other to the ac feed (through the internal centrifugal switch) terminal that does NOT supply the other Capacitor terminal.
In other words, one side of the supply, say L1, goes to the cap, the other side of the cap goes to the start winding the other side of the start winding goes to L2.
The run winding, may be easier, as it goes to L1 & L2.
Both sets of windings are either series or parallel, depending on voltage.
M.
 
I did take a look at the wiring diagram, most Americam made motors that are single phase and are reverseable have the wires number 1,2,3,4,5&8 ( with 5&8 being the start winding ). But the diagram that you show almost looks like 3 & 4 is the start winding.
The best thing to do is get a ohm ( resistive ) reading across your motor leads, two of the readings should be the same, as that will be your running winding. The other reading should be alot higher, as that would be your starting winding ( you should put a jumper wire accross the start capacitor, to get a correct reading accross the start winding )
Get back to us with those readings and we should be able to help you out.
 








 
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