Dc servo motor control

Yes it is a 7i92, I could do that with a male-male adaptor, both have female plugs.

When installing the old esab cable for the -10+10V analogue signal I have noticed 2 things:

1. I Had pins the wrong way around. I had signal ground and the -+10v Incorrect!!

2. On the esab wiring the 0v signal pins and the shield are connected, , this is not what I would have expected, I thought that the shield would have went to ground bar and signal ground would be separate. Is it best to connect the signal ground along with the shield? 

 Tommy told me so image missing /media/kunena/emoticons/laughing.png

  3mm walls and 8mm floor.

  some wiring done, metal cable ties would be better, tomorrow I will get a few enclosures, one to mount THcad on side of plasma unit and another for mounting Z motor drive and PSU. 

 

Much better!
As for the analog signals being tied to ground, i am sure i separated them, but i am also sure i did not mention that to anyone i helped with the retrofit, so it should work both ways, granted you have good grounding in the shop.

Tommy, my next decision, IHS. I had planned to use ohmic so I removed the esab sensor (2 prox sensors on a air cyclinder). But with the problem earlier Im not sure what to do, you advise to setup first without ohmic, what method should I use? Im used to ohmic on my smaller machine. So far I can think of:

1.  Refit the proximity sensor and air piston setup, however sometimes this was troublesome dependant on the geometry of small parts which were already missing  from the cut sheet.

2. Fit a float switch, the magnetic holder is not strong enough and the torch is knocked off before the z axis carriage lifts, however perhaps it is best to modify this as would be reliable.

3. Fit relay ohmic, I could disconnect the ohmic probe from the circuit during cutting with perhaps 2 relays during cutting. Would it be best to use spdt relay with the resting postion pin to ground?

4. Same as 3 but use thcad plate sensing.

What method is most sucessfull for this type of machine? This machine will not be used for less than 5mm sheet, mostly 8-25mm plates

2

I agree with Tommy, #2 for the materials that you are cutting.

If you did go with #1, QtPlasmaC can do offset probing so that the proximity sensor would probe at the actual pierce coordinates.

If you did go with #3, use a solid state relay, not a mechnical relay.