H.E.S. 24NCS Lathe (24 X 60) conversion

Well, two steps forward and another two steps back. I hooked the VFD drive, a GS3 2015 from automaton direct to the 7i76 card. I connected the pins like this:

Pin 1 to the Analog signal Common
Pin 2 to AI1 (0 to 10v)
Pin 3 to +10v power source
Pin 4 was left blank
Pin 5 to DI1 (Start / Stop)
Pin 6 to +24v power source
Pin 7 to DI2 (Forward / Reverse)
Pin 8 to +24 power source

I then changed parameters in the drive so that it would recognize the external controls. Then was the time for the big test and….. it worked, kind of. It started the spindle when I told it to. The speed control was a little off but was getting there. I had to go into the INI file and change some of the spindle parameters from the original pncconfig. I had to change the min and max to -1800 and 1800 respectively and the speed control to 1800 (this is from memory so not sure I am labeling them exactly correct but close).

This worked to the point that I had perfect control of the spindle turning forward (m3) but not with the spindle in reverse(m4). With the reverse direction the speed is opposite of what it should be. I need to go into the hal file and insert and "abs" so that it will convert the negative value to a positive value to feed to the driver (something like that. I have not done this yet but don't think it will be a big problem).

This is as far as I go before I started loosing ground, at the same time I was doing this work I had connected a dynamic braking resistor to the VFD (on the theory that it is better to stop the spindle faster then slower. I started the spindle with linuxcnc and then stopped the motor, the braking resistor worked in stopping the spindle in about half the time of normal. This was great but when I tried to start the motor with linuxcnc again I was not able to. I was able to check the VFD by changing the parameters back to keypad control (away from linux) and the motor will start fine and stop faster with the braking resistor.

I broke out the volt meter and started checking the signal on the 7i76, when checking between pin 1 and pin 3 it shows 10v (as it should as this is the supply voltage). I then went into linuxcnc and entered a start signal (checked this with the hal meter and it showed true and that it was setting the speed) then checked between pin 1 and pin 2 (this pin should show the control voltage going to the VFD between 0 - 10v). With the speed set to full I was not able to get even one volt to show on pin 1. I looked at the hal file to see if I might have made a change or deleted something that I shouldn't have. I will keep looking to see what I can find.

I hope all that I have written makes sense, if anyone has any suggestions I would be grateful to hear it. I have a few things I am going to check and then will have to start getting inventive. The second step back was that towards the end of the day the min. limit switch on the z axis started to trip. I am pretty sure this is a loose wire so I need to trace that out (I have not labeled my wires very well but this might be a time to start.



Canner

Could you post your hal and ini files here?

Sure, here they are.

That looks basically correct except for the pncconf bug of connecting spindle
enable to motion.motion-enabled rather than motion.spindle-on

If you might check the output of the digital potentiometer with no load
and spindle set to 1/2 speed (900 RPM)

Ok, I am still tracing out the limit fault and will not be able to test anything until that is corrected. I might need a new limit switch so this could take a while but will respond as soon as I have the result.


Thanks

Okay, I fixed the limit fault (loose wire) and then restarted the computer and machine. When I did this I had control of the spindle through linuxcnc again, so looks like the problem is solved.

I will correct the speed control in reverse with the abs command. After this it will be time to start working on attaching the spindle encoder and then wiring that into the 7i76.


Thanks

Okay, I adjusted to hal file so that speed control is working correctly either direction. Now on to the encoder. I am attaching my hal file in case someone would like to see how I did it.

So I built the adapter to mount the encoder to the lathe, this is my first time posting pics so I hope this works as intended.

I need to wire the encoder into the 7i76 but have some questions. I see the that spindle encoder should be wired TB3 pins 7 through 12 as follows:

7 ENCA+
8 ENCA-
9 GND
10 ENCB+
11 ENCB-
12 +5VP

The encoder is from automation direct TRD-GK 1000-RZD incramental (quadrature) rotary encoder. The wiring printout for the encoder is:

Blue: 0v
Brown: Power supply
Black: OUT A
White: OUT B
Orange: OUT Z
Shield: GND

Some of these seem obvious on where they should go but others I am not sure. Again I searched the forum but could not find an answer on how these should be wired. If someone could point me in the correct direction I would appreciate it.

Also will I need to make any changes to my hal or ini file to get this encoder working?


Thanks