Machine Gone Wild

[bill south]

I've developed a new problem with my lathemaster conversion servo/gecko controlled machine. I can turn on the power to the controller with the computer off and all servos drive violantly in one direction. If I keep the machine in manual reset off and turn it on with the control compter on and functional, it will reset and behave. I've been using this same configuration for yesrs not and this has just started. I've made no modifications to the system. Nothing moved (like the control console) or anything. It just started having nightmares. Any suggestions?
Bill

[LeeWay]

You might want to consider a charge pump.
It is a signal that is given out by the controller when it is ready to go. They come included on some BOB's.

I recently bought a C1G from CNC4PC and it has an enable function. It needs 5 VDC to run the BOB and without the BOB powered up, it sends no signals. So effectively there is a charge pump switch to turn on the BOB and enable the controller. It is better than not having anything.

[escott76]

I've developed a new problem with my lathemaster conversion servo/gecko controlled machine. I can turn on the power to the controller with the computer off and all servos drive violantly in one direction. If I keep the machine in manual reset off and turn it on with the control compter on and functional, it will reset and behave. I've been using this same configuration for yesrs not and this has just started. I've made no modifications to the system. Nothing moved (like the control console) or anything. It just started having nightmares. Any suggestions?
Bill

Without the computer on, or without some kind of safeguard, you can never be sure what's going on at the parallel port in terms of voltage. As has been mentioned a charge pump will keep the drivers from moving until there is a valid "heartbeat" from the control computer. The other option, which isn't a bad idea, is to only turn on the drivers/controllers after the computer is on. I do both, it's cheap insurance.

[bill south]

Thanks Guys;
I should have mentioned this earlier but I was at home and could not remember my card manufacturer. I'm using a Sound Logic Encoder Interface with the built in charge pump. Again, nothing like this has happened in the past and I've always turned on the control system before firing up the computer. Just habit I guess. Again, all the axis drive in the same direction all the way to the stops at full speed and end with a bang. I'm sure I would let the magic smoke out or strip some gears if I let it continue to run.
What baffels me is why the motors just run wide open with no signal telling them to move. And since all three Geckos are firing, what kind of stray signal or loss of a ground or logic high would cause this to happen.
My other cnc graver doesn't run amuck like this. I still think something is wrong like a cooked BOB.
Has anyone had a run away experience like this????

Think I'll just quit and go to the bar!!!!!!

Thanks .
Bill

[SCzEngrgGroup]

I've developed a new problem with my lathemaster conversion servo/gecko controlled machine. I can turn on the power to the controller with the computer off and all servos drive violantly in one direction. If I keep the machine in manual reset off and turn it on with the control compter on and functional, it will reset and behave. I've been using this same configuration for yesrs not and this has just started. I've made no modifications to the system. Nothing moved (like the control console) or anything. It just started having nightmares. Any suggestions?
Bill

Something is preventing the encoder signals from reaching the Geckos - there isn't much else that will cause that with servos. It's certainly not related to the BOB. Disconnect the BOB, and I bet it still does the same thing. Since you have the SoundLogic board in there, I would suspect that. Disconnect it, make sure the encoders are directly connected to the Geckos, and I bet the problem goes away.

Regards,
Ray L.

[KIMFAB]

You might have lost a ground somewhere. That will also cause this problem.

[bill south]

Thanks Guys;
I'm betting on the sound logic board since the servos are driving blindly. Tonight I'll pull the controller and check the voltages. May be the $10 5V power supply I'm using finally expired. I'll actually post the results and findings so maybe it will help others later.
Thanks Again!
Bill