Mesa 7i76e Power off no Stepper movment

hello Together,

I build a plasma table with a mesa 7i76e. It seemed that I lost my power wile I was cutting. Only a test cut but it was in a cut. After that I thougt the Mesa killed kompletly but lukily after I solved the Power issue It came back. But yet I have no movement anymore. I tried different configs with the same result. But I get readings from the endstops and float switch I can see them in the halshow.
Did I kill the Mesa Card? Or is it possible to repair it? I´m not sure if it was the power shut down or the Plasma itselfe.
I am happy of any helpe. I made a floating head and a water table the last days and with lot of searching around the web it worked out very good till this point..

Regards,

Philipp

I thing I found my Problem. I have no 5v between pin 1 and 6 on Tb2 but on TB3 there is 5 V. Is Possible to solve that issue?

I am happy about any helpe.

I found something. It is the same topic?

forum.linuxcnc.org/38-general-linuxcnc-q...orking-fine?start=10

And I can replace the 2 chips.

That sounds like the external 5V was shorted (TB2 and TB3 has separate PTC devices to supply 5V to the TB2 and TB3 connectors)

I would recheck with the connectors removed in case you have an external short

thanks for your answers. I try it tomorrow. I checked the power supply after the stopp and saw that the +24v wire came lose. I solved that but before that I removed the tb3 power connector could that lead to my problem?

So I have more news. I mesured the voltage again and I have 5V between Pin 6 and  Pin 1 and there is also Voltage on the step gens something around 4.1.On TB3 I mesured 3.3V on the 5 Volt line is this correct?I think the chips U 20 is broken. In the middle of the chip it looks like a very tiny hole. Can somebody please claryfie that? And can that happen if I dissconnected the power in on the TB3? Becase of stupidity....
here is a picture of the mesa card: www.dropbox.com/s/hmn0siqbzrgpy61/20220109_1030412.jpg?dl=0 uploade in the thread didn´t worke out.

Disconnecting 5V power from TB3 would not cause an issue.
I would not expect U20 to be damaged unless something other than 0 to 5V
was applied to P2 or TB3

should not write post in a hurry. I made a few misstakes.
I made another picture and marked the port I removed tb3 power in 24V dc.

And I ment the U19 not U20 direktly beside TB2.

www.dropbox.com/s/9416udwt0n7n0mx/202201...453markiert.jpg?dl=0

Thanks a lot for your help

Hello,
thanks a lot for your help I changed U19 and it seems that all is fine again.
But I am a bit afraid of firing the plasma Torche without knowing what cases this issue. Ihave still 2 chips left so I can make a change again but that is not a good solution.
I have a few ideas but only ideas. Could anybody help me with these questions.

1. loos kabel on the power supply
2. removing the power input.
3. a shortage I didnt found yet.
4. A problem with the input Voltage. back feed from a relay?
5. Field Power and regulated Power on one Power supply.

Thanks a lot for your hepl.