possible reasons for a "short to ground" error mid print?

r123

Mid-print started getting "Error Short to Ground reported by driver 0" (the X-axis stepper on my Railcore).

Stopped the print, examined for a loose connector (that happened once before) annd errors kept rolling in every 5-10 secs. Out of ideas restarted the machine and now the errors stopped (as per console output below).

Then tried homing the machine and errors came back in abundance (together with defective motion). Then took the lid off the machine (allowing everything to cool down after 70C chamber print) AND unplugged stepper connector, examined and replugged.

Having restarted machines homes normally and all errors gone.

What are the possible causes of the problem?

although the connector looks fine I know a loose connector can cause this problem;
could stepper overheating cause the problem? (they were running hot - though outside the build chamber they share some aluminium frame);
anything else?

12/06/2021, 21:06:18 Connection established
12/06/2021, 21:06:17 Connection interrupted, attempting to reconnect...
HTTP request timed out
12/06/2021, 21:06:05 Error: short-to-ground reported by driver(s) 0
12/06/2021, 21:06:00 Error: short-to-ground reported by driver(s) 0
12/06/2021, 21:05:56 Error: short-to-ground reported by driver(s) 0

ps have these: https://www.moonsindustries.com/series/nema-23-high-precision-hybrid-stepper-motors-b020403

r123

@r123 well, it's happened twice more and I feel like an idiot just wiggling connectors. So have remapped the X from Drive 0 to Drive 4 and we'll see!

dc42

@r123 which Duet are you using? If it's a Duet 3 or 3 Mini, and you are running the drivers in stealthChop mode, then the problem could be that you are running in stealthChop mode at speeds that are too high. This is documented in the Trinamic data sheets:

Veti

@r123 said in possible reasons for a "short to ground" error mid print?:

they were running hot

how hot. those steppers are Insulation Class B, 130℃.
see https://www.engineeringtoolbox.com/nema-insulation-classes-d_734.html

r123

More than halfway through a 15hr prinit and printing like a dream (literally, I'm still half-asleep!). So far, no Driver 4 errors.

@dc42 i'ts a Duet Wifi (and this iis the same print file as earlier failures) so that eliminates the trinamic thing.

@veti thanks for the insight on stepper classes. The cases were probably not over about 60C so still have to do eggs in the pan.

Remapping the driver didn't touch the connector at the stepper end so now inclined to think that issue is at PCB end of the wire. The PCB, the male or the female connector. Time will perhaps reveal.

davidewen

@dc42

I have a Duet 3 mini 5+.
I've been printing for days and suddenly in the middle of a big job I get Error: short-to-ground reported by driver(s)3.

Extruder is a Bondtech DDX3

I've swapped the driver for the original Ender 6 and same error.

Any idea how to correct it?
David

dc42

@davidewen said in possible reasons for a "short to ground" error mid print?:

I've swapped the driver for the original Ender 6 and same error.

Please explain exactly what you mean by that.