Unable to configure bed heater

Weevil

@phaedrux I'll give it a shot.

Weevil

@phaedrux That did not work. I got the following message:

Warning: heater behaviour was not consistent during tuning
Auto tuning heater 0 completed after 4 idle and 25 tuning cycles in 3679 seconds. This heater needs the following M307 command:
M307 H0 B0 R0.317 C276.8 D1.57 S1.00 V22.7
Send M500 to save this command in config-override.g

As with all tests, the beep alarm would go off each time the bed heats up. I went ahead and saved the code with M500 but the issue remains. I would be happy if I could just disable the alert. It appears to function fine.

Weevil

@phaedrux I think the issue is the board is treating the bed heater like a nozzle heater. It is running tests with the fan on and fan off.

These codes:
M308 S0 P"temp1" Y"thermistor" T100000 B4138
M308 S0 P"temp0" Y"thermistor" T100000 B4138

They look identical. Perhaps there is a code for bed heaters.

Phaedrux

@weevil said in Unable to configure bed heater:

I think the issue is the board is treating the bed heater like a nozzle heater. It is running tests with the fan on and fan off.

What M303 command are you using to tune the bed?

M303 T# will tune the heater as a tool with the fan
M303 H# will tune the heater as a heater without the fan

https://duet3d.dozuki.com/Wiki/Gcode#Section_M303_Run_heater_tuning

Weevil

@phaedrux I thought I was using H. I'll double-check when I get home. But the M308 command, shouldn't the T100000 B4138 be different for bed?

engikeneer

@weevil depends what thermistor you have. B4138 is the default the config tool uses so is almost certainly not right for your setup. You probably should find out the correct values for your thermistor (for both hotend and bed).
Having said that, it should only affect how accurate the measured temperature is (and probably won't make much difference at lower temperatures used by the bed).

Weevil

@engikeneer The thermistor for my Keenovo pad is an NTC100K if that helps.
Also note, the heated bed size is 300x300.

Phaedrux

@weevil said in Unable to configure bed heater:

The thermistor for my Keenovo pad is an NTC100K if that helps.

Chances are the B value should be B3950 in that case.

Weevil

@phaedrux Thanks, I'll try that (fingers crossed).

Weevil

@phaedrux M303 T# produces this error:
M303 H# tests with the fan
M303 T1 S60
Error: M303: tool 1 not found

theruttmeister

@weevil said in Unable to configure bed heater:

@phaedrux M303 T# produces this error:
M303 H# tests with the fan
M303 T1 S60
Error: M303: tool 1 not found

Not surprising...

M563 P0 S"MYTHprint" D0 H1 F0
M563 P0 D0 H1 F0

You have configured Tool 0. There is no Tool 1.

Although I'm not sure why you are getting the fan running when the heater is.

Also you have a random H without a value:

M106 P1 S1 H T45

Doubt it's causing the problem, but can't hurt to fix.

Phaedrux

@weevil said in Unable to configure bed heater:

M106 P0 S255

This may need to be M106 P0 S1 H-1 to work correctly as a part cooling fan. That might have something to do with it.

Weevil

@theruttmeister My bad, for some reason I was thinking T as temp probe, not tool. Using the code M303 T0 S60 goes to the nozzle. I need this to test the bed heater. I'm not sure what code I am missing.

Phaedrux

For the tool you use M303 T0 S### (or M303 H1 S###) and for the bed heater you use M303 H0 S##.

The tool tuning is intended to allow the algorithm to use the part cooling fan during the tuning process so that it can compensate for any fan cooling effect. It's not supposed to do that when tuning the bed though, so that may be a bug. Or maybe it's taking into account the fan effect for the bed heater now as well.

Weevil

@phaedrux Yeah, it's still running tests with the fan. I'll see if the error goes away after the test.

Weevil

@phaedrux Calibration finished with the same error code:

Warning: heater behaviour was not consistent during tuning
Auto tuning heater 0 completed after 3 idle and 25 tuning cycles in 3658 seconds. This heater needs the following M307 command:
M307 H0 B0 R0.377 C62.4 D1.54 S1.00 V22.7
Send M500 to save this command in config-override.g

It still errors out about the heater taking too long.

dc42

@weevil said in Unable to configure bed heater:

It still errors out about the heater taking too long.

Send M307 H0 to check that it is using the values resulting from tuning.
What is the expected heating that it reports in the error message?

Weevil

@dc42
Out of an act of desperation, I ran the calibration again.

M307 H0 returns this:
Heater 0 model: heating rate 0.377, cooling time constant 62.4, dead time 1.54, max PWM 1.00, calibration voltage 22.7, mode PID
Computed PID parameters: setpoint change: P307.5, I31.363, D331.4, load change: P307.5, I69.412, D331.4

I must be crazy. This is the 5th time I ran M303 H0. This time, it worked. I just wish I could silence the long beep or at least lower the volume during the initial warm-up. It's probably a necessary safety feature.

Should I be concerned with the warning: Warning: M307: Heater 0 appears to be over-powered. If left on at full power, its temperature is predicted to reach 209C?

Phaedrux

@weevil said in Unable to configure bed heater:

I just wish I could silence the long beep or at least lower the volume during the initial warm-up. It's probably a necessary safety feature.

What is beeping and when exactly?

@weevil said in Unable to configure bed heater:

Should I be concerned with the warning: Warning: M307: Heater 0 appears to be over-powered. If left on at full power, its temperature is predicted to reach 209C?

Well you should be somewhat concerned, yes. It's telling you that the heater could reach 209c if a runaway failure condition happens. So just be aware of what might happen if that were the case and then try and mitigate as best you can. Thermal cut off fuse is a good idea. Smoke detector. That sort of thing.

Weevil

@phaedrux When the heater is first warming up from room temperature, there is a loud, continuous tone coming from the board. After it reaches the target temperature, the tone stops. Even when the temperature drops, the tone does not return when the board engages the heater to warm up again.
I am not sure if this helps but I have both outputs from my power supply feeding the 2 inputs to the board. When I first got the board, a Facebook group advised me to set it up that way.