intermittent heater failure warning while heater working fine

[jens55]

As the title says .... I get occasional pop ups on the Duet web panel telling me that there was a heater failure but there isn't an actual failure - no heaters report as failed and the printer is merely printing away with rock steady temperature.
I have no idea where to start looking for the issue because as far as the printer is concerned there is no issue. On the web panel I can just dismiss the warning. No reset of any nature is required.
Has anybody run into this ? Where could I even start to look ?

[Veti]

what firmware version do you have? have you tried updating to the latest firmware?
can you post the actual message. it should be in the g code console.

[dc42]

In the Troubleshooting section of the wiki, there is a page about how to avoid spurious heater faults.

[jens55]

@Veti , I will try and capture a screen shot when it happens next. I will also try to capture a shot of the gconsole.
Screenshot from 2019-09-14 00-32-52.png

[jens55]

@dc42, thanks, I am aware of that write-up. The problem here is that the heater is not actually faulting so the write-up doesn't seem to apply.

[dc42]

Sorry, I didn't read your original post carefully enough. Which firmware version are you using?

[Phaedrux]

From the screen shot it looks like 2.0.3/1.23/1.22.6

[jens55]

Here are the two screen shots - one of the heater failure message and then the g console page

There were no errors for a while but I wasn't printing anything either. I decided to close the Duet window and open it up again and that is when the error appeared. So, in this case, it appeared on startup of the web panel and note that Duet shows both bed and the first extruder as 'active' (ie no fault.
I am under the impression that the error happened before when it was not related to starting the web panel but it could have happened when I refreshed the page. My embedded monitoring picture freezes quite regularly and I restart it by hitting the refresh button.
I will try to pay closer attention to exactly when the error happens in the future.

Edit: tried a bunch of refresh operations and sure enough the error happens every time.

Edit 2: Just to point out that this is a relatively new issue. I will reboot the computer in a while to see if maybe something got weirded out in the system. I run Linux and sometimes there is a substantial time span before reboots. I have noted though that some programs (ie Cura) seem to have a bit of a memory leakage issue and consuming more and more memory over time. Maybe something got clobbered somewhere.

Edit 3: Issue still exists after reboot

[Veti]

can you try a different browser? or try in incognito mode?

[jens55]

Tried in Chrome - same issue
Tried in 'private' mode on Firefox which is presumably 'incognito' mode and it has the same issue.
Good call though and a thing that gets me on a daily basis - I block scripts and other stuff and the vast majority of web sites fail with Firefox somewhere sooner or later until I unblock them. It is disgusting how many trackers and related crap I have to allow in order to see what the web site should look like. Duet , refreshingly, does not try to load 20 other web sites or trackers or what have you.
I am not sure if Duet needs cookies enabled.
My Chrome installation is vanilla without any blocking so if the issue had gone away I would have confirmed that it was the blocking ... but it wasn't.

[jens55]

Just a slight update - it seems that the Duet web interface might reproduce the last system error. I received a 'filament out' error message instead of the 'heater fault' error message today.

[T3P3Tony]

@chrishamm any idea why DWC may be repeating old error messages?

@jens55 if you have a chance the try connecting over USB as well and see if you get the error in a terminal.

[dc42]

@jens55 said in intermittent heater failure warning while heater working fine:

Just a slight update - it seems that the Duet web interface might reproduce the last system error. I received a 'filament out' error message instead of the 'heater fault' error message today.

When DWC connects to a Duet, in effect it asks "What have I missed?". So yes, it is possible to receive old alerts on first connection.

[jens55]

@T3P3Tony said in intermittent heater failure warning while heater working fine:

@chrishamm any idea why DWC may be repeating old error messages?

@jens55 if you have a chance the try connecting over USB as well and see if you get the error in a terminal.

I have never connected via USB ... is this something pretty straight forward with a Linux computer ?

[jens55]

Another interesting discovery: The error went away after the Duet went through a power cycle.
Under normal circumstances, the power on my Duet is never shut off so this tidbit of information was discovered only by chance.