control loss or glitch gorilla cnc

[woodman08]

i seem to have a problem that cannot be resolved .With the cnc machine powered up, turning on the computer (win xp) during booting the cnc machine drives the z axis down by 2.5 to 3 inches( loss of control ).
I have changed all the settings on the parallel port ,changed the cable to the gorilla cnc and tried 3 computers ,problem does not go away and i'm afraid to use the machine as it could damage the z axis or the gantry.i have been shutdown for a week so far.
I don't know what to do
"http://www.youtube.com/watch?v=EngUvy3YKAE"]YouTube - control problems

[TOTALLYRC]

The obvious thing is to start the computer first and then turn on the cnc controls. It is "normal" for the pport to do weird things when starting up and shutting down.
The other thing is to activate the charge pump function if available on your machine.
The charge pump is specifically designed to prevent this kind of problem.


Mike

[ger21]

Exactly what Mike said. You either need to set up a charge pump in Mach3, or do NOT power up the machine until Mach3 is running, and power down the machine before closing Mach3.

[woodman08]

I will take a look at the setting of the charge pump,but don't forget mach3 is not running ,nothing software wise is running.
And yes i can just leave it and start the cnc after but if the computer ever glitched and rebooted(murphy's law) ,the head will be driven 2.5 to 3.0 inches which is into running into some steel damaging the gantry ,z axis or the router.
Can you tell me where charge pump setting is (plugins?)

[TOTALLYRC]

If your breakout board supports the charge pump feature, then what happens is that nothing from the breakout board on down will function until it sees the charge pump signal, 20khz or something like that on the proper pin. It was designed for exactly the problems that you describe. It prevents any movement or outputs from happening untill mach3 is in full control of the machine.

Mike

[woodman08]

Well i found out that this is the way it is,if the cnc is powered up during computer boot up it will move, manufacturer says its how the parallel port works on some computers .I have tried 5 computers and they all drive the machine crazy dangerous.The gorilla people suggested a charge pump board that will stop this at a cost to be about $300.00,I'm starting to learn that this machine has no stops ,no preventions, its minimal for looking after a mistake or glitches and could cause serious costly trouble.
I never knew this from the start and its less than 1 year old

[ger21]

$25 for a charge pump.

http://www.cnc4pc.com/Store/osc/prod...products_id=51

[woodman08]

thanks --will look into this,is there much involved to tie it into the exsisting equipment

[ger21]

The easiest way would probably be to add a second parallel port to your PC, using a PCI card, then add a cheap breakout board to hook it up to, like this.

http://www.cnc4pc.com/Store/osc/prod...roducts_id=131

Then you don't have to mess with the existing setup.

[woodman08]

thanks i will get a second LPT port (pci card) and then order the add on you recommened,this sounds like a cheap fix
Thanks for the help.
Its difficult to know what to change as the machine came with no documnetation but i will get to understand even if i have to completely replace the electrical in the future

[woodman08]

I added the second parallel port and that did the trick ,the computer can be started or turned off and the cnc machine just sits there --problem and worry soved and resolved.
now for some stops,heat sinks and cooling.
The electronics box needs heat sinks and cooling recommended by the gecko drive manufacturer