Correction: just figured out the multimeter. The PSU is pushing, 24.3v.

@bot yep, insulated.

@T3P3Tony

Here is a better shot of the area you requested

@bot yep, insulated.

@dc42 It reads 24.3 on both sides of the fuse.

Not sure what else to do here...

Not to be presumptuous, but I submitted the Duet3d warranty form provided by reprapworld.co.uk yesterday. I'm having a hard time sitting on my hands waiting for responses.

@T3P3Tony 

At work right now, but I had taken this this photo after I disconnected everything to see if the issue was caused by wiring. I since removed the heater wiring, and I'm having the same symptoms with just a bare board.

@dc42 said in Printing fine, then, undervoltage event:

Does the Duet report the VIN voltage at 9 to 11V all the time? or does it report 24V most of the time?
Have you measured the voltage between the terminal block screws, to check that you are really getting about 24V there?
Is there still 24V there even with the bed heater running at full power?

1. When I turn the machine on, it reports between 13-14v. If I rerun M122 every 60 seconds-ish, it drops about 1v each time, until it bottoms out around 9.5v. It doesn’t actually fail until I start a print.

2. Yes, I measured at the terminal block screws: 24v

3. Yes, turned on bed heater and hot end and both measure 24v at the screws for the entire preheat. Meanwhile, M122 shows voltage dropping.

Edit: @Phaedrux tried the other psu, no change

@dc42 vin terminals are good. I even took the wires out and installed the included ferrules. Same result.

It’s confusing because I’m getting correct voltage off the board, but diagnostic says it’s under voltage and it’s stopping for the under voltage event.

@Phaedrux The PSU is giving consistent 24.3v readings. I can try a different one, I’ll let you know

Started another print - Stopped 7 minutes in

Here is the console log:

7:02:15 AMError: G0/G1: insufficient axes homed
7:01:40 AMError: Attempt to move motors when VIN is not in range
7:01:35 AMG28
Error: Attempt to move motors when VIN is not in range
6:59:44 AMError: G0/G1: insufficient axes homed
6:59:36 AMCancelled printing file 0:/gcodes/Case Lid _ PLA _ 26m.gcode, print time was 0h 6m
6:59:35 AMWarning: VIN under-voltage event (9.5V)
6:52:55 AMM32 "Case Lid _ PLA _ 26m.gcode"
File Case Lid _ PLA _ 26m.gcode selected for printing

Anybody heard of this problem before?

Just went through all my connections again, voltage is still dropping.