Need Help Boss5 to Gecko/Mach2?

[braidmeister]

I just picked up a good running Boss5 Bridgeport CNC and want to convert it over to Mach2 control w/Campbell breakout board and Geckos. I want to keep the original power supply and steppers.

Does anyone know what the Bridgeport Boss5 power supply specs are? I am asking because my biggest concern is over amping the Geckos. Has anyone on here done this type of conversion? Is there a way to limit the amperage of the PS to Geckos to prevent smoking them? My other option is to use the Larken drives, (max 16A) but I hear from a friend that they are a bit noisy compared to Geckos.

Thanks in advance,
-Brady

[gus]

I may be wrong, but I don't think you can 'over amp' the drives. A fuse on each would prevent it anyway. Can you not limit the current output on the gecko?


Keep as much of the original bridgeport power panel as possible, they are really nice. Too bad the controls weren't.

[braidmeister]

Yeah, that's what I hear...I plan on keeping the power supply and just gutting the control box.

I'd like to hear from anyone who has done this, what drivers they used etc. Not really interested in a Centroid or other retrofit package...just driver recommendations.

Thanks!
-Brady

[HillBilly]

The original setup used the secondaries of a 3 phase transformer to make 3 separate power supplies, one for each axis. There is a another single power supply that chops across a saturatable reator for each axis to limit the current.

For your setup you would disregaurd the single supply and reators. Just guessing the separate supplies will be around 100VDC maybe higher. I used the original drives in my setup.

A word of advise the original steppers do not like microstepping. If your ideal is to get better positioning accuracy than the stock 0.001 for the Series I, or 0.0005 for the Series II you may want to consider DC servos with encoders.

Darek

[braidmeister]

Nope...not looking to get any better resolution. If it does, great...if not .001 is good enough for the time being.

You didn't say what drivers you were using. If they are putting out 100v+/- then the Geckos are out of the question.

-Brady

[HillBilly]

The only think I changed was the computer. The K8 plug into XDI board accepts quadrature drive signals. I originally used MaxNC software but have switched to Mach 2.
I use the MaxNC CL option on Mach 2 to get the quadrature signals.

Darek

[braidmeister]

So you are saying that it is possible to use the BOSS5 XDI board to suck in quadruture signals???!!!!

What model BOSS are you using? Wondering if this is one of those BOSS6+ options or if it is valid for the BOSS5...If so...I need to throw one of those dancing bananas on here! LOL!

-Brady

[HillBilly]

The XDI board outputs these signals to the drives. Basically in the side cabinet everything below the terminal and fuse strip is removed and replaced with a PC.

Darek

[braidmeister]

Thanks Darek!

I may pick your brain a bit as time goes on. I just got it last Friday and haven't even powered it up in my shop yet (just finished huge carbon fiber parts order last night at midnight)...Now I can play a bit with the BP.

Thanks!
-Brady

[braidmeister]

The XDI board outputs these signals to the drives. Basically in the side cabinet everything below the terminal and fuse strip is removed and replaced with a PC.

Darek

So if I understand this correctly, the breakdown would be like this:

Mach2 (setup for MaxNC Waveform data output) -> Campbell breakout board -> X8 connector on XDI board -> SDB -> Motors

Not sure if the Campbell board will work...I definately want the port isolated.

-Brady

[HillBilly]

Here is a couple of links to the breakout board I built. It is a duplicate of the circuit on the XDI board.

Parallel Port Opto Isolation ???
What is your opinion of MaxNC mills?

Darek

[machintek]

FYI. The Bridgeport drives have 10 amp fuses for the DC side of the stepper drives. Fuses 12,13, and 14. The current is limited to 8.0 to 8.2 amps by the ACC card using those saturable core reactors. Interesting is that the 8.0 amps has the DC volts down to about 9.5VDC when the motors are stationary. When they are running at max, the current drops to just above 2 amps (unless the motors are tired and weak) and the voltage comes up to about 60 VDC.
The XDI board interfacrs to the UFP board in the control panel and puts out the axis drive pulses through the SMD boards. These signals are isolated by opto couplers on the XDI (ZDI on the BOSS 6).
The BOSS 6 did step in .0005 inches and was available as a series 1 and 2 machine.

George W.