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Chuck Keysor
07-27-2011, 06:13 PM
Hello. I have finished re-assembling my PRT alph, and just did the first electrical test, to check the Z, Y and X movements.

Z checked OK, in that it moved as the instruction book said it should.

But when I tested the Y axis, I expected it would move in reverse, because when I purchased this machine 1 1/2 years ago, the Y stepper motor was mounted on the wrong side (it was on the same side of the X car as the cable arch!) When I reassembled this machine in my basement, I followed the directions, and the Y stepper is now on the opposite side of the cable arch (though I replaced the arch with an echain). And in fact, the Y car moved in the wrong direction when I tested it.

My machine came with the PRT manual, and a PRT alpha conversion instruction set. The PRT manual gives full test instructions, and the alpha conversion manual does not. So, the PRT manual says it is easy to correct the backwards motion of the Y car, by reversing the green and black wires of pins 3 & 4 of the gray Wago connector on the cable that goes into the motor driver box. They say this can be done with a small screw driver.

Problem 1:
The wires on this connector are green/#4 and yellow/#3. So, I suspect my PRT directions do not apply to the PRT that has been upgraded to an Alpha. And, the Alpha conversion directions and trouble shooting guides do not say anything about reversing motor directions.

Problem 2:
My connectors are not grey. They are natural Nylon. In my past life as an electrical engineer, who had to do and undo lots of Molex connectors (never used Wago), these don't have the little locking ramps that can be undone with a little screw driver. And, when I bought my used PRT alpha, it didn't come with any connector tools. I have attached two pictures, so you can see what connectors I have. Where is the cheapest place I can get a tool for this style of connector, and what is the correct ordering number? (Or can these in fact be changed without a special tool (I also have had lots of practice messing up connectors when not using the right tools!)

Your guidance is appreciated! Thanks, Chuck

myxpykalix
07-27-2011, 08:03 PM
chuck,
make sure these wires are in the correct slot on your connector. I had a problem on one of my connectors for my probe and after breaking it 3 times we finally figured out that it was wired wrong from shopbot. After all they are only human right?:D

srwtlc
07-27-2011, 08:15 PM
Easiest tool is to go to the software and under VU, put a - or take away the - for the Y axis.

Brady Watson
07-27-2011, 09:25 PM
Just switsh the BLACK and the GREEN wire on the conectore that goes in the board for your Y motor ,and your good to go .

WHOA! The machine in question is an ALPHA. You cannot swap wires like that - unless you have a STANDARD tool with a 4-wire connector.

Just sign (-) the VU in front of Y and you will be fine.

-B

steve4460
07-27-2011, 11:15 PM
OOPS I didn't catch that alpha Part . I hope you didn't make the change I posted .

Chuck Keysor
07-28-2011, 12:34 AM
Thanks everyone for the quick replies. I haven't made any changes yet, as I have been out for the evening. But tomorrow I will make the indicated software change. I have no idea where the desired software panel is located, but no doubt I will find it.

I'll make a post tomorrow to confirm that the Y axis is in working order. Then I will make a new post on the X axis, which has a different problem. :(

Thanks again, Chuck

Chuck Keysor
07-28-2011, 02:21 PM
Thanks Scott. Your solution to correct my reversed Y car motion worked. Not only did it work on the Y axis, but it also worked on the X axis, which I found was also reversed. Chuck :)