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Glad you got it worked out.
For future reference, a transformer will only give you it's rated output voltage when it's input voltage is correct & it is loaded to it's rated current. As line input voltage can vary about 10% acceptably (causing equivalent output variation) & open circuit vs full load voltage can vary by upto 50% on some transformers, the operating voltage requirements of transformer powered equipment is usually pretty wide. These variations will cause the motors to spin faster or slower... The purpose of the encoders is to track rotation so the controller knows how much movement the motor has done & can adjust accordingly.
Your missing earth bonding may affect the reliability of small signal communication between boards but is unlikely to be causing any issues, in your case it's there for safety & any metal parts that could become live in the event of a broken wire or component failure should be bonded to earth with wire rated to carry at least circuit breaker current.
Obviously you still don't want anything wired to earth that shouldn't be as it will blow the fuse (as you discovered). In that case, if the earth wasn't connected properly the machine would continue to work & the case would be at mains potential!
 
Glad you got it worked out.
For future reference, a transformer will only give you it's rated output voltage when it's input voltage is correct & it is loaded to it's rated current. As line input voltage can vary about 10% acceptably (causing equivalent output variation) & open circuit vs full load voltage can vary by upto 50% on some transformers, the operating voltage requirements of transformer powered equipment is usually pretty wide. These variations will cause the motors to spin faster or slower... The purpose of the encoders is to track rotation so the controller knows how much movement the motor has done & can adjust accordingly.
Your missing earth bonding may affect the reliability of small signal communication between boards but is unlikely to be causing any issues, in your case it's there for safety & any metal parts that could become live in the event of a broken wire or component failure should be bonded to earth with wire rated to carry at least circuit breaker current.
Obviously you still don't want anything wired to earth that shouldn't be as it will blow the fuse (as you discovered). In that case, if the earth wasn't connected properly the machine would continue to work & the case would be at mains potential!
Well I think I have proved I am not an electrician but sometimes being stubborn is just as good. I cant wait to get this mill operational so I can prove I aint a machinist either.
 
Well the good news is now the key board will make everything move, the bad news is I got to learn how to run it. Any ways, time to order a phase converter so I can make the darn thing run. Any suggestions. I thought about a American rotary phase converter, but they are kind of pricey. Leaning toward something like this, https://www.amazon.com/Phase-Conver...se+to+3+phase+converter&qid=1622145293&sr=8-5
I don't see why that converter wouldn't work. Just make sure to get one that is rated for the current or HP that your motor pulls. Personally, I would get the one sized at 2x what I need. It's solid-state and transistors don't like current or voltage spikes. They tend to let their smoke out. Tubes are far more forgiving.

If there is more than 1 motor, you will need 1 for each motor.

My only concern is that these things are basically a switching power supply on some serious steroids, and switching supplies make a TON of noise that may screw up the PLC comm. lines. If you can mount it in a grounded metal box, and place it a few feet away from the machine, you will lower the chances of interference by a substantial amount.

ETA:
I'm not sure, but for some reason, I want to tell you to multiply the current need of the 220V 1-phase line by 1.73 (square root of 3). So if you need 10 amps @ 3-phase, size the 1-phase wire for 17.3 amps.
 
I don't see why that converter wouldn't work. Just make sure to get one that is rated for the current or HP that your motor pulls. Personally, I would get the one sized at 2x what I need. It's solid-state and transistors don't like current or voltage spikes. They tend to let their smoke out. Tubes are far more forgiving.

If there is more than 1 motor, you will need 1 for each motor.

My only concern is that these things are basically a switching power supply on some serious steroids, and switching supplies make a TON of noise that may screw up the PLC comm. lines. If you can mount it in a grounded metal box, and place it a few feet away from the machine, you will lower the chances of interference by a substantial amount.

ETA:
I'm not sure, but for some reason, I want to tell you to multiply the current need of the 220V 1-phase line by 1.73 (square root of 3). So if you need 10 amps @ 3-phase, size the 1-phase wire for 17.3 amps.
I am kinda torn between using the listed phase converter and the American rotary converter. Plans call for finding a good lathe and what I find might be a 3phase machine also. This would mean buying another phase converter for the lathe. The big rotary converters can run a room full of machines, but they are also loud and need mounting outside the building to help control the noise and one big enough to run several machines aint cheap. Also with the rotary, you have to run electrical wiring to each machine from a single power source, that alone can add hundreds of dollars to the cost to install. I already have the 220v single phase in three locations in the shop and all I have to do is make the pigtail connection from converter to outlet. This would also make the machine easier to resell if I decide I want to get rid of it. Most folks already have a 220v single phase outlet in their shops if they do any kind of welding. The converter I listed is minimum needed to run the mill and I will probably go with the next size up. The machine has its own electrical box on the back that the converter might fit in already. Havent measured yet. The good is that I can buy several for multiple machines for less than the cost of a single rotary. I hadnt considerd the interference factor of the inverter so I might have to add some sort of filter.
 
I agree with Bobby, when driving motors or other largely inductive or capacitive loads the supply needs to be significantly more than the rated current. Industrial motors commonly have special breakers or fuses around twice the rated current to prevent nuisance tripping on startup.
As far as electrical noise from the switching converters goes some have better filtration than others & it's usually (but not always) the cheaper ones that skimp in these areas... They may also lack reasonable thermal & overload protection.
He is also correct about the greater single phase vs 3 phase current draw, & there will be some inefficiencies to add to that.
Essentially a 3 phase 1A motor would need to be provided at least 2A to account for startup current etc, & if that were run by a converter the single phase to it would need to be around 4A
 
I wouldn't bother with a rotary converter. I think the phase converter I used when I had my Bridgeport in my garage was less than 100 bucks, but that was fifteen years ago. It didn't look fancy like the one you linked to, it was more of a junction box looking thing.

What is the make/model of your mill?
 
I wouldn't bother with a rotary converter. I think the phase converter I used when I had my Bridgeport in my garage was less than 100 bucks, but that was fifteen years ago. It didn't look fancy like the one you linked to, it was more of a junction box looking thing.

What is the make/model of your mill?
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I changed the model to be one with single phase input. And cheaper!
I changed the model to be one with single phase input. And cheaper!
I ordered the https://www.amazon.com/Digital-Phas...se+to+3+phase+converter&qid=1622218047&sr=8-4 before I saw your reply. Should have it by next week. $246 with tax and free shipping.

I am still having problems with the x and y jog. Seems to be trying to run both axis at the same time and shaking the machine to death. I did tighten the belt on the axis motors and that smoothed it out a lot. Not sure how to trouble shoot the problem. Signal to motors has to be bleeding over somehow. I am going to unhook the power from one servo at a time and see it if I can isolate which side is bleeding over.
 
Do you have a manual for the controller? Without one you are going to really struggle.
As far as the shaking, there could be a number of problems. If there is any looseness or backlash between the motors and the ballscrews, it will be unstable. Also if the motor drive was replaced and not tuned to the responsiveness of the system, it will be unstable. If one or both of the encoders is not working correctly, it will not position correctly and possibly run away and crash.

This video seems to show a similar machine:

Jerry
 
I have downloaded a operators manual and I found a trouble shooting manual on the new linux cnc forum. I havent had time to study either manual yet. I think one is 66 pages and the other is 78 pages. I did get the GPS inverter the other day, Havent hooked it up yet. The tables seem tight but I dont think that is my problem. When I run one axis, the other axis wants to take off at the same time. I am guessing bleed over. All the wiring is cracked and brittle. I also think I need to clear out the computer, or what ever they call it on this machine, and get rid of what ever the old owners had programmed into it. I found a line by line code on the linux cnc forum for the prototrak plus on just how to do that. Again, I just havent had time to mess with it. I am considering doing a update conversion to fusion 360 and the mach 4 software. I simply cant afford to pay South West Industries asking prices for their parts. They asked me $12,000 just to upgrade to one of their newer systems. $30k for a complete rebuild. I can buy a new bridgeport clone with 3 axis cnc for that price. A brand new bridgeport is only $17grand.
 
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