Tree 2UV reversing switch rewire

I guess your machine has been modified from the original- in your Tree diagrams there are/were contactors that pull for forward and reverse which are powered by the step down transformer. Sounds like your setup is different now
Seems like if it ran before on 440 it should run on 220. Are you sure the motor wires and drum switch are configured correctly?
I suspect an issue there, rather than a bad motor. Just tryin' to save you some money
-M
ps what is your 3 phase power from? Do you have actual 3 phase coming in or are you using a VFD or RPC?
have you tried bypassing the drum switch and running power direct just for a test?
 
Last edited:
The 2UVR does not have a transformer unless it was added to power lights or some other accessory that was added later. Electrically it is a very simple machine. 2 motors, one of which has a reversing switch for it. There is no low voltage circuits or contractors.

What you are describing sounds like single phasing the motor, this is when only 2 of the 3 wires have power to them, The motor will run but in either direction and have very little power, but often needs a spin to get it started.

Can you tell if the motor is making the correct speed and power when in forward?
You said the motor starts and runs fine forward but not in reverse?
If this is true then the motor is fine and you have a power issue in the switch. A 3ph motor runs on the same 3 wires whether it is in forward or reverse. All that happens for reverse is the the switch reverses any 2 wires.

It is possible to read 220 V with no load and near zero with a load. You will have to test the 3 wires at the motor for power with the motor connected. If you at least have the motor spinning, even in single phase, you have plenty of time to test voltage without hurting anything.
 
Flyinfool,

It could very well be single phasing but it would be a problem in the motor wiring. I get the correct voltage on all three lines coming into the machine. I also get the correct voltage on all three lines coming out of the switch.

Is it possible to have a broken wire at the motor wiring connection that when the motor has been sitting will pass the current to the motor but when it has run and the wire warms up wont carry the current due to to few strands still connected. When I was testing it today for the umpteenth time it started in forward the first time then in order to get it to run I would have to spin it first. I could spin it in either direction then hit the switch and it would run.

I have a feeling I might have broke a wire in the process of changing it to 220 volts, as it ran like a dream when I was testing the machine before it was loaded on my trailer. Just trying to get it to run. To find this wire could be problematic as the wiring is OLD, HARD Easily cracked.

I am not trying to be difficult here, I appreciate your willingness to help I am just puzzled by this
 
Power coming out of the switch does not mean power to the motor. It could be a broken wire between the motor and the switch. You still need to check for power at the motor to be sure it is getting there. If there is power getting to the motor then it is either a bad connection when you rewired for 220 or a broken wire in the motor.

Try this
With power to the machine turned off.
At the motor side of the switch check all 3 power wires with a volt meter to ground. This is just to be sure that your power switch is actually turning off all 3 wires, many 3 PH switches only actually turn off 2 of the 3 wires. If all 3 wires are dead to ground, then switch your meter to ohms and check each of the 3 wires to ground, all should read infinite, as in no connection. Then check the resistance of each pair of the power wires, they should all be the same (or very close to the same). If one wire is bad or one motor winding is bad it will show up here without messing with the motor wires. If this test shows a problem then you will have to start messing with those old hard wires to track it down.
 
Flyinfool,
You are the best. I did the checks just as you explained. There was one wire that when in conjunction with any of the other two would show a different reading. I have been up to my elbows in wires this morning, I did find the problem ( I think ) so after finding the problem I went over all the wires sticking out of the windings. If there was a break or soft spot in it I would check it out to make sure it was OK then I would cover the wire with heat shrink.
I have tested the motor multiple times in both directions several times thru out the day and it has always started.

I cannot thank you guys enough for all the help with this problem. Now to learn how to mill correctly.

Thank You so much

Mike
 
Glad you got it figured out.

FWIW, I really like my Tree 2UVR.
 
Back
Top