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All I can add is a bit of advice on replacing the chip.
My method of removal is to carefully cut the leads on the chip, not too much pressure just lightly with an exacto knife. Then clean up the pads with desoldering braid.
There's also the flood method, but it requires some very deft action with the soldering iron.
Replacement is pretty easy, lookup the "drag method" on YouTube.
If you have experience with a proper desoldering station and hot air gun, ignore what I've said as you probably realised I'm a ham fisted Aussie.

except you are confused between the torch tip and the shield. Some torches (Hypertherm, and Thermal Dynamcs for example) Have a seperate shield that is not shorted to the workpiece.

So in general if you have an exposed tip you can't do ohmic sensing because its shorted to the material.

Some machines (ie Swiftcut) lower a seperate probe and ohmic probe off that. This can be done fairly easily in QTplasmac with a pneumatic cylinder as all the required signals are there.

I had burned up a few outputs on my 7i84, was able to replace the chip, its the same one as above it in the top row. Worked ever since. As for the blown chip, do the relays have diodes? Is there any potential for a spark from AC to travel back to the mesa from the relay? I personally use mosfet output protectors to protect the expensive mesa cards

Yeah, an instant dead short on the 24V rail could damage the output chips.
It may be repairable by replacing (probably both) NCV7608s
Unfortunately they are obsolete so a bit hard to find, I can probably
mail a couple to you if you want to try.

To make sure the damage is limited to the output chips, so worth repairing,
you could remove the output chips and see if you still have communication
with the 7I84.

Other option would be to replace it with a 7I84U (which is fully compatible
and a bit more rugged)

Tntmold wrote:

Is there a place that has instructions for new users on how to set up an ethercat machine once lcnc and ethercat is installed?

Not really except the sticky posts here. Ethercat works with a master and slaves (devices). There is an open source Ethercat master from Etherlab that runs on Linux. A user wrote a hal driver that allows Linuxcnc to interface with the Ethercat master. There is a licence incompatibility between Linuxcnc and Ethercat itself so we have never been able to openly support it. Plus you had to compile source code to get the master installed. In recent times, Etherlab made their master available in  a Linux repository and kindly agreed to host our hal driver on that repository, So now anybody can install Ethercat easilly and we can configure apt in our installers on the downloads page so anybody who wants Ethercat can access that repository.

Once Ethercat is installed its set and forget but the installation is more complex because you need to configure two different systems.

Hi Peter,
I blew a component on my 7i84 on my Maho mill.

History :
I had a loose screw in my pendant shorting a 24V wire, dropping the CB for the 24V rail. I removed the screw. The machine worked normally for a week.

I was using the machine to set up a job, and when I switched my spindle on it,  it dropped a CB on one of the main 3 phase CB's. That was poor judgement...

At that time  I was commanding a different spindle speed, so the gearbox comp would have tried to twitch the spindle back and fourth.  These are the pins for the twitching relays...
net activate-spindle-twitch-cw  mh400e-gearbox.twitch-cw           => hm2_5i25.0.7i84.0.2.output-06
net activate-spindle-twitch-ccw mh400e-gearbox.twitch-ccw          => hm2_5i25.0.7i84.0.2.output-07

However it could also have been one of these three...
# --- SPINDLE-CW ---
net spindle-cw   motion.spindle-forward => hm2_5i25.0.7i84.0.2.output-12
# --- SPINDLE-CCW ---
net spindle-ccw  motion.spindle-reverse => hm2_5i25.0.7i84.0.2.output-11
# --- SPINDLE-ON ---
net spindle-on   motion.spindle-on      => hm2_5i25.0.7i84.0.2.output-13

The damage is pretty clear...
 

 

1/ Do you have specific recommendations what I need to be looking as a root cause? I suspect it would be a short in the output connected to the sixth pin from the LH on the top row of that IC. Which output would that be please? Any additional troubleshooting suggestions I would appreciate.
2/ Any chance of fixing this? Any guidance appreciated.

Cheers,
Mark
 

Hello,

I've been following this topic for a long time, great work.

I looked at the jerk with the Hal oscilloscope, there seemed to be outliers.
see image. 

Hi Daz, no issues from my side. I'd probably do the same if I had time.

Well, that was quick. The customizations are all applied. The update script did a good job, but did miss one thing, in case anyone cares: the main HAL file for my mill led with the following loadrt lines:
I think the final "[TRAJ]AXES" should have been changed to "[KINS]JOINTS", at least if I'm reading the update_ini code correctly. But it was not, leading to "Ini variable '[TRAJ]AXES' not found".  Please correct me if I'm wrong, since I've made the change manually.  (For the record, my config file had no [EMC]VERSION line.)

So now all I need is for USPS to deliver my Mesa card.