Smoked YAxis chip on Hobbycnc pro board

[wjfiles]

I have a router using Win2K,Mach3, Hobbycnc PRO board Rev1,4x 23-305 ds8
Steppers,33volt Power supply,
Settings are all checked as per specs, the router has worked without problem for
18 Months.Nothing was changed.
Switched on one morning and the Y-Axis did not work. The chip was smoked.
I installed a new board,Checked and double checked all aspects of the board,
switched on and the Y-Axis motor was locked up hard and did not step, just a
faint buzz.
Checked the motor on another A-xis .worked fine.
I checked all the config in Mach and everything was as it has been for months.
I may be wrong but could this problem be caused by corrupt drivers in Win2k And Mach3.
I am posting here due to lack of response in the "Yahoo Group"
I am currently using 3 Axis but need the 4th.
What do I check next.
I seem to recall another similar situation on a complete new build that the Y
axis did not work but I don,t recall what the fix was.It was the same
configuration as this machine.
Any help will be appreciated.
WJF

[john_100]

Hi wjfiles ,

1, check the the cable to your Y axis you may have a break
in the cable that could have blown the IC on the first board

2, as the Y axsis works does not work

double check the components in that part of the board are all in
the right place and all the solder joints are OK
its easy to have a short circuit were tracks past between pins on the IC for instance
is the reference voltage correct at TP Y ? over 2V drive goes into sleep mode

you should have continuity from pin 5 ( stepY signal ) on the 25 pin D type connector and pin 10 on U2 ( Y axis driver )
when the step input is clocked you should see the voltage at the test point increase if the FET's Q3 and Q4 are working







John

[wjfiles]

Thanks for the reply john,
I have completely removed Mach3 and reinstalled.
I have reconfigured mach3 ,Motor tuning, ports and pins.
The board has been modified to bypass the Idle current and is controlled now by Mach. This mod was done more than a year ago and works fine,( no more missed steps since.)
Vrefs check OK @.41volts , board power is 5.1 volts
and the power supply to TB5 is 33 volts
I have connected different motors to the Y and there is still a problem,
The motor connected to the Y is no longer dead but grinds.even though the motor is tuned to the same settings as the other Axis
By connecting different motors I assume this eliminates the broken cable,or faulty motor. I have no way of checking the parallel port. I will look at changing the motherboard in the next day or so.
This machine has run for many months, this just problem appeared at switch on one morning
wjf

[eaglezsoar]

You have eliminated the possibility of a bad motor by substituting other motors but what about the cable? Have you replaced the cable feeding the
motor from the Y axis on the board?

Best of Luck, Carl

[eaglezsoar]

You have eliminated the possibility of a bad motor by substituting other motors but what about the cable? Have you replaced the cable feeding the
motor from the Y axis on the board?

Best of Luck, Carl

[wjfiles]

Originally Posted by eaglezsoar You have eliminated the possibility of a bad motor by substituting other motors but what about the cable? Have you replaced the cable feeding the motor from the Y axis on the board? Best of Luck, Carl

Sorry for delay getting back.
My motors each have it's own cable.
I switched the Y motor to the A axis and I am running with 3 axis.
Searching for answers I noted that similar problems with the Y axis are not uncommon, maybe co-incidence ??
I am a little disappointed that Hobbycnc seem to rely on a forum to support their product
Thanks Carl
WJF

[wjfiles]

Updating my previous posts.
As mentioned I have blown chips on the Yaxis on to boards that worked OK for many months. Checking all wiring ,configs and anything else I could think of I could find no logic for the blown chips.
Recently a CNC builder friend mentioned that I should never Stop the machine with the Stop button in Mach3 without first using the feed hold or I risk blowing chips ??
After some thought, both boards failed after Stopping with the Stop button in Mach to avoid a broken cutter.
Question , are there any guru's out there that can throw some light on this.
I did not have an Estop wired on the machine and always relied on Mach control. buttons.
WJF