Jackal, yes that is the controller I was talking about. They make it in 3 versions, the C model is for analog drives and is the cheapest one but its limited to 3 axises. They also make a D model for digital drives which is 4 axis (and cost more) and they also make an S model for stepper motors.
As 3t3D mentioned if you already have analog drives it will be reasonably easy to hook up. If you need new drives the high end approach would be to get the D model. However although
they designate the S model for steppers, I believe it would also work with step/direction based servo drives like Vipers/Geckos/etc. but the pulse rate is probably lower than the D model, which would limit your rapid speeds. But depending on your performance goals, the S model may be good enough and I think its cheaper than the D model, but may also be limited to 3 axises.
The interface issues you will have are in 4 areas- connecting to the drives, connecting to the encoders, connecting to the spindle and connecting to the limit and home switches.
Depending on the encoder types you currently have and the controller you decide to go with you may have to replace your axis encoders, most people get the new ones from US Digital, their prices are pretty reasonable. Connecting the limit/home switches should be pretty straightforward unless they used some oddball design but I would definitely use new wiring there.
I would also definitely go with new motor drive wiring as old flakey wiring causes a lot of hassles for people doing these kinds of upgrades. mcmaster dot com sells special multiconductor wire for CNC use (flexible and oil resistant) by the foot so you don't have to buy a big roll of it. Some people like to use fancy connectors for their motor and encoder connections but as far as I'm concerned every extra connector is just another potential trouble source. I like to wire directly from the drives to the motors and encoders directly using the terminal strips typically supplied on the motors and drives. Its more work if you ever need to swap drives out for testing or something like that, but you really shouldn't have to do that very often.
Hopefully your current spindle drive has inputs to control on/off and forward/reverse as well as a voltage input to set the spindle speed. If so this will be easy to hook up. If it doesn't have these inputs and you want full spindle control, which I recommend, then you would need to buy a new VFD for the spindle.
As far as I know those chinese sold controllers are legit units, and those are pretty killer prices. But even with the Siemens controller you're still looking at a fair amount of work to get the machine shop ready, so think through that issue.
If I was starting from scratch today it would be a tough choice between the Siemens controller and a Mach approach, but if I had the dough available (I didn't at the time) I'd probably look hard at the Haas TM-1 with a tool changer.
Also there has been some other discussion of this controller on PM, if you search "802" you'll probably hit it.
One other issue, all the "hardware accelerators" that have been developed for Mach all make me pretty nervous. They require additional software support beyond even the basic Mach interface and I've seen several of them come on the market with great fanfare but not fully functional software and then fade away a year or two later after never really having all the bugs taken out.
My recommendation would be to only consider a Mach solution that uses the standard parallel port approach, this is the most commonly used version and gives you the best chance of minimizing flakeyness. There are several companies that supply interface cards for this parallel port approach and those cards work fine, the ones I'm saying avoid to are the ones that implement some or all of the motion control also.
Good luck-
Paul T.
www.power-t.com
Do all electronics come from there now?
