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Wes[_2_]

wrote:

Buy a box of fuses!

Find the wye connected set and isolate the remaining 3
pairs.

I tried running it on the center connected wye. Drew too much current and popped the
breaker.

The numbers marked on masking tape for that series of wires didn't match the data plate.
Should have been 4,5,6 were marked 7,8,9.

I noticed two wires had red tape on them, two had black tape on them, and two had green
tape on them.

Well that had to be the high voltage wiring scheme that some maintenance tech must have
tagged the wires with at some point to id them for himself.

So I thought, why not try it. Undervolting an unloaded motor isn't going to kill
anything. Motor started fine configured for 480 V using my rpc generated 240 V.

At this point I thought I had it. Those colored wires had to be the normal 4,7 5,8 6,9
connections. And since three of those wires were center connected, I thought I knew which
ones were the ones to form the second wye. Well that didn't work. So I inverted the coil
polarity which didn't work.

Then I thought, go back to where you were before the invert, then rotate the connections
each way. Single phasing motor showed 40a 80a depending on which two legs. On the third
try of parrelleling the wyes, we got a nice sweet 9 amps or so and no tripping of my
circuit breaker.

This would have so much easier if the motor would have run on the one wye, maybe if we
could have spun it up to speed it would have kept going.

Motor looks like it was made during the 1930's from the revision dates on the data plates.
Runs nice and smooth. Uncle is very happy with his nephew's persistance today.

Uncle lended a hand to the lathe restoration project today. Another thread for that.

Btw, I did get your book eventually from Amazon, took many, many months. It is a good
book.

Wes