Hotend PID tuning

baballuci

Hi guys,

I'm not sure what i'm doing wrong here, i'm trying to PID tune a 12v 30w E3D hotend,

I'm sending command,

M303 H1 S280 P0.1

But getting error,

Error: Temperature reading fault on heater 1: temperature above limit

no matter what P setting i use i get the same error.

Any suggestions? I can't set S any higher because i get,

Bad parameter in M303 command

Cheers
Charlie.

dc42

It looks to me that you have a massively over-powered heater. Are you using a 12V heater cartridge on 24V power?

You can increase the temperature limit if you need to using the M143 command. The default is 262C.

baballuci

You got me worried there, had to double check. It's definitely wired to 12v.

I'll try M143 and report back.

Cheers

dc42

You can also reduce the P parameter to below 0.1 if you need to. Or try the 1.18 beta firmware, which doesn't need a P parameter when auto tuning, just a target temperature (which will be overshot somewhat).

baballuci

I went for the new 1.18beta, it did give a warning,

Warning: Heater 1 appears to be over-powered and a fire risk! If left on at full power, its temperature is predicted to reach 602C.

Saved with M500.

Cheers
Charlie.