Earthing problem

Hi all
I need a quick fix,
Problem is, when Mach 3 plasma is booted up my keyboard arrow signals with move the axis on screen ok,
When I switch on the power inverter to power the stepper drivers the signals is still ok on the screen,
But when I switch power on to the stepper drivers the screen is non responsive and sometimes I get message from the computer saying the USB being used has lost its ,

I have changed to new keypad and new computer that we had spare for back up.
Could this be a earth problem somewhere

Thanks Guys

It could be an earthing problem. From what you describe it sound like that the stepper drives are so electrically noisy that they are blanking the USB signal to the board. Maybe a well shielded USB cable would help.

Did this system ever work correctly? If so, then what has changed?

Hi Jim,
Yea this system has been running about 5 years now
With no problems
I know the guys cutting last week did hit the table
A fair bang with the fork lift,
But I did check around table for maybe nipped
Cables but see no problems
I'll try a better shielded cable tomorrow

Thanks again Jim

Quote:

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Originally Posted by Jim Dawson

It could be an earthing problem. From what you describe it sound like that the stepper drives are so electrically noisy that they are blanking the USB signal to the board. Maybe a well shielded USB cable would help.

Did this system ever work correctly? If so, then what has changed?

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Hi I have found a new problem with this
On y axis and z axis, when I power up the drivers to
Them two axis and put the tester on the shield around the
Cable that goes from them to the motors I seem to get slot of DC voltage inaround 24v and this also disables the computer keyboard,
So going to rewire them two motors in new and see
If it's a broken or crossed wire somewhere
Also if I connect these shields to the earth on the drivers
It also freezes keyboard
I have tried earthing table to ground peg earth and earthing table to control cabinet

Tis dam confusing

Quote:

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Originally Posted by Dem1

Hi I have found a new problem with this
On y axis and z axis, when I power up the drivers to
Them two axis and put the tester on the shield around the
Cable that goes from them to the motors I seem to get slot of DC voltage inaround 24v and this also disables the computer keyboard,
So going to rewire them two motors in new and see
If it's a broken or crossed wire somewhere
Also if I connect these shields to the earth on the drivers
It also freezes keyboard
I have tried earthing table to ground peg earth and earthing table to control cabinet

Tis dam confusing

---

Well that makes no sense. I would think that earthing the table would be the proper thing to do. I think you have a short to a shield somewhere.

Quote:

---

Originally Posted by Dem1

When I switch on the power inverter to power the stepper drivers the signals is still ok on the screen,
But when I switch power on to the stepper drivers the screen is non responsive.
Could this be a earth problem somewhere

Thanks Guys

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Have you set up an earth star point ground where the service GND terminates also?
The USB power is already grounded through the PC supply, if this is a tower PC etc.
The stepper P.S. common may also require connecting to this star point.
I usually make a habit of ground all supply common's if possible, whether instructions say or not.
Max.

Well I have it sorted now ,
I bought new breakout board HG08
And 2 drivers. CDW 872
Along with new cabling on table and cabinet
It worked out cheaper fix for me rather than spending man hours troubleshooting and down time cutting.

Thanks all again for help
Great forum here
h

Quote:

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Originally Posted by Jim Dawson

Well that makes no sense. I would think that earthing the table would be the proper thing to do. I think you have a short to a shield somewhere.

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Happy to hear it's working again :cheers: