PID auto tuning in RepRapFirmware dc42 1.17d

Hi,

I'm using a Duet 0.6 board, just upgraded the firmware to 1.17d.
Fisher 3D Printer uses 19V, 60W hotend heater.
When I ran M303 H1 P0.5 S260 for PID auto tuning, it overshooted temperature and failed.
So I reduced PWM to 0.4 (40% of the maxium).

I applied the PID values in config.g as below.

; M303 H1 P0.4 S260 
; (P0.5 Auto tune of heater 1 with P=0.50 S=260.0 cancelled 
; because temperature limit exceeded. Use lower P or higher S in m303 command.
; 12:57:33 PM
; M307 H1
; Heater 1 model: gain 597.8, time constant 68.9, dead time 4.2, max PWM 1.00, m
ode: PID
; Setpoint change: P4.9, I0.072, D14.4
; Load change: P4.9, I0.514, D14.4

M307 H1 A597.8 C68.9 D4.2 S0.4 B0 ; Set Heater 1

I printed one test model and it was alright except warm up time got longer about three times compared to 30 seconds.
Am I doing it right?

Thanks in advance,

Edited 1 time(s). Last edit at 02/03/2017 09:02AM by janpenguin.

That's correct except that you should not have the S0.4 in the M307 command. You will find it heats much faster without it.

Edited 2 time(s). Last edit at 02/03/2017 09:29AM by dc42.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].