Hello,
I am upgrading to Gecko drives and mach 3 on my old boss 4 series II mill.
I plan to use a RPC and use the original speed control.
My questions are:
1: Can I use the original 3 phase to 80 v power supply for my drives? This transformer has 3 secondary windings I was thinking I could wire it like the boss with 3 seperate power supplys for X, Y, and Z. The transformer secondarys are rated at 80 V AC so I think I would have to build 3 voltage regulaor circuits. I will atatch a the original print and a print with my modifications.

2: My steppers are the Sigma steppers, Can someone explain how to wire them to a 202 Gecko? I found the thread on here about the superior motor wire up but nothing on the Sigma's. I have a picture of my motors i will include in this thread.

3: Should I use gecko 202's or 212's?

Thanks

Here is the original print

You could use the three separate secondaries for each supply, you will need to check if they are different voltage secondaries.
Depending on what DC you want to end up with as this will be quite high voltage to regulate down at any power. Check the other tap to centre and see if they are lower on the other winding.
Al.

As soon as I get my RFC going I will try powering it up and see what I get on the other tap.
Thanks

3: Should I use gecko 202's or 212's?



Both are rated at 7 amps and your motor is rated at 8 amps. Some people have used them with the original motors with no problems and other have blowm them.

Darek

Is there any drives that are rated for 8-10 amps that would work better with these steppers?
Thanks

Found alot of info on this thread: http://www.cnczone.com/forums/showthread.php?t=19637&highlight=sigma+motors

I should just have to wire motor leads 1 and 3 to the Gecko term 4 and 3 and motor leads 2 and 4 to gecko term 6 and 5. Then jump 7 to 8 and 5 to 6.

Please let me know if I am not correct.

Does anyone know of a drive I could use that would alow me to run in unipolar?



I have also decieded to use a single power supply for all 3 drives, I will use the bridge rect. and caps off the boss parts. I have not decieded what transformer to use yet.
Thanks