3.5.0 beta 4, Unable to tune heater at low PWM

presto

This maybe related to the recent post 3.5.0 beta 3 minimum PWM frequency. Issue as stated in title. Below are the details of the hardware & logs. Bed heater is driven by SSR with 5Hz PWM frequency at max PWM of 85%.

Hardware and firmware info

Product	              Short Name	    Version
Duet 3 Mini 5+	       Mini5plus	3.5.0-beta.3+
Duet 3 Expansion       TOOL1LC	        TOOL1LC 3.5.0-beta.3+
Duet 3 Expansion       TOOL1LC	        TOOL1LC 3.5.0-beta.3+
Duet WiFi Server	 n/a	        2.1beta4
Duet Web Control	 DWC	        3.5.0-beta.3

Tuning parameters

M303 H0 S60 A31 Y2
Auto tune starting phase 1, heating up
Auto tuning heater 0 using target temperature 60.0°C and PWM 0.85 - do not leave printer unattended

Bed heater config

; Bed Heater
M308 S0 P"temp0" Y"thermistor" T100000 B3950 A"Bed Heater" ; configure sensor 0 as thermistor on pin temp0
M950 H0 C"out0" Q5 T0 ; create bed heater output on out0 and map it to sensor 0
M140 H0 ; map heated bed to heater 0
M143 H0 S105 ; set temperature limit for bed heater 0 to 105C
M307 H0 S0.85 ; set max PWM to 85%

DWC Console

5/30/2023, 10:19:18 AM	Connection interrupted, attempting to reconnect...
5/30/2023, 10:19:09 AM	Emergency stop, attemping to reconnect...
5/30/2023, 10:19:04 AM	Connection established
5/30/2023, 10:19:04 AM	Connection interrupted, attempting to reconnect...
Operation failed (Reason: Service Unavailable)
5/30/2023, 10:19:02 AM	Connection established
5/30/2023, 10:19:02 AM	Connection interrupted, attempting to reconnect...
Operation failed (Reason: Service Unavailable)
5/30/2023, 10:18:58 AM	Connection established
5/30/2023, 10:18:58 AM	Connection interrupted, attempting to reconnect...
Operation failed (Reason: Service Unavailable)
5/30/2023, 10:18:55 AM	Connection established
5/30/2023, 10:18:55 AM	Connection interrupted, attempting to reconnect...
Operation failed (Reason: Service Unavailable)
5/30/2023, 10:18:52 AM	Connection established
5/30/2023, 10:18:52 AM	Connection interrupted, attempting to reconnect...
Operation failed (Reason: Service Unavailable)
5/30/2023, 10:18:48 AM	M303 H0 S60 A31 Y2
Auto tune starting phase 1, heating up
Auto tuning heater 0 using target temperature 60.0°C and PWM 0.85 - do not leave printer unattended

I am unable to issue M122 command as DWC is practically unusable. Physical reset is required.

T3P3Tony

@presto i expect this is not related to the PWM frequency you are choosing, but to something else, possibly the power supply or wifi interference.

does this issue occur when heating the bed normally (i.e. not when tuning?)

presto

@T3P3Tony No issues on DWC or PanelDue when heating bed. Do note that the low PWM does not work, the bed does not heat up until a heater fault occur which a reset is required.

P/S

M950 H0 C"out0" T0 ; create bed heater output on out0 and map it to sensor 0

Did a few test with different PWM ie Q5, Q10, Q100 all did not work in my case, bed does not heat up, auto-tune causes DWC to go into reconnect loop. Without the Q parameter all is normal.

dc42

@presto is this an AC mans bed heater and DC-AC SSR, or DC bed heater with DC-DC SSR? If it's a DC bed heater, what is its specification, and what PSU are you using to power it?

presto

@dc42 It is an AC silicone bed heater (240V supply voltage and 50Hz) with a DC-AC SSR.

presto

@dc42 Just updated to 3.5.0 beta 4. M950 Q5 works normally at heating the bed. But when M303 tuning, DWC will still go into a reconnect loop. Below is the diagnostics after reset.

=== Diagnostics ===
RepRapFirmware for Duet 3 Mini 5+ version 3.5.0-beta.4 (2023-06-08 23:40:14) running on Duet 3 Mini5plus WiFi (standalone mode)
=== RTOS ===
Static ram: 102996
Dynamic ram: 124172 of which 0 recycled
Never used RAM 12032, free system stack 186 words
Tasks: NETWORK(2,nWait,19.7%,219) HEAT(3,nWait,0.0%,333) Move(4,nWait,0.0%,358) CanReceiv(6,nWait,0.1%,672) CanSender(5,nWait,0.0%,337) CanClock(7,delaying,0.0%,351) TMC(4,nWait,1.2%,116) MAIN(1,running,72.3%,704) IDLE(0,ready,5.9%,29) AIN(4,delaying,0.8%,266), total 100.0%
Owned mutexes:
=== Platform ===
Last reset 00:01:05 ago, cause: software
Last software reset at 2023-06-14 15:41, reason: User, Gcodes spinning, available RAM 11676, slot 0
Software reset code 0x0003 HFSR 0x00000000 CFSR 0x00000000 ICSR 0x00487000 BFAR 0xe000ed38 SP 0x00000000 Task MAIN Freestk 0 n/a
Error status: 0x00
Aux0 errors 0,0,0
MCU revision 3, ADC conversions started 65609, completed 65607, timed out 0, errs 0
MCU temperature: min 42.4, current 43.5, max 43.9
Supply voltage: min 24.1, current 24.1, max 24.2, under voltage events: 0, over voltage events: 0, power good: yes
Heap OK, handles allocated/used 99/8, heap memory allocated/used/recyclable 2048/192/84, gc cycles 0
Events: 0 queued, 0 completed
Driver 0: standstill, SG min 0, read errors 0, write errors 1, ifcnt 30, reads 5932, writes 13, timeouts 0, DMA errors 0, CC errors 0
Driver 1: standstill, SG min 0, read errors 0, write errors 1, ifcnt 30, reads 5932, writes 13, timeouts 0, DMA errors 0, CC errors 0
Driver 2: standstill, SG min 0, read errors 0, write errors 1, ifcnt 30, reads 5931, writes 13, timeouts 0, DMA errors 0, CC errors 0
Driver 3: standstill, SG min 0, read errors 0, write errors 1, ifcnt 30, reads 5931, writes 13, timeouts 0, DMA errors 0, CC errors 0
Driver 4: standstill, SG min 0, read errors 0, write errors 1, ifcnt 30, reads 5932, writes 13, timeouts 0, DMA errors 0, CC errors 0
Driver 5: standstill, SG min 0, read errors 0, write errors 1, ifcnt 21, reads 5935, writes 10, timeouts 0, DMA errors 0, CC errors 0
Driver 6: standstill, SG min 0, read errors 0, write errors 1, ifcnt 21, reads 5934, writes 10, timeouts 0, DMA errors 0, CC errors 0
Date/time: 2023-06-14 15:42:13
Cache data hit count 111873654
Slowest loop: 11.05ms; fastest: 0.15ms
=== Storage ===
Free file entries: 19
SD card 0 detected, interface speed: 22.5MBytes/sec
SD card longest read time 1.0ms, write time 0.0ms, max retries 0
=== Move ===
DMs created 83, segments created 0, maxWait 0ms, bed compensation in use: none, height map offset 0.000, ebfmin 0.00, ebfmax 0.00
no step interrupt scheduled
=== DDARing 0 ===
Scheduled moves 0, completed 0, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state -1
=== DDARing 1 ===
Scheduled moves 0, completed 0, hiccups 0, stepErrors 0, LaErrors 0, Underruns [0, 0, 0], CDDA state -1
=== Heat ===
Bed heaters 0 -1 -1 -1, chamber heaters -1 -1 -1 -1, ordering errs 0
=== GCodes ===
Movement locks held by null, null
HTTP is idle in state(s) 0
Telnet is idle in state(s) 0
File is idle in state(s) 0
USB is idle in state(s) 0
Aux is idle in state(s) 0
Trigger is idle in state(s) 0
Queue is idle in state(s) 0
LCD is idle in state(s) 0
SBC is idle in state(s) 0
Daemon is idle in state(s) 0 0, running macro
Aux2 is idle in state(s) 0
Autopause is idle in state(s) 0
File2 is idle in state(s) 0
Queue2 is idle in state(s) 0
Q0 segments left 0, axes/extruders owned 0x0000000
Code queue 0 is empty
Q1 segments left 0, axes/extruders owned 0x0000000
Code queue 1 is empty
=== CAN ===
Messages queued 12085, received 14080, lost 0, boc 0
Longest wait 3ms for reply type 6053, peak Tx sync delay 102, free buffers 18 (min 17), ts 329/328/0
Tx timeouts 0,0,0,0,0,0
=== Network ===
Slowest loop: 11.69ms; fastest: 0.00ms
Responder states: MQTT(0) HTTP(0) HTTP(0) HTTP(0) HTTP(0) FTP(0) Telnet(0)
HTTP sessions: 1 of 8
= WiFi =
Interface state: active
Module is connected to access point 
Failed messages: pending 0, notready 0, noresp 0
Firmware version 2.1beta4
MAC address bc:ff:4d:e7:aa:88
Module reset reason: Power up, Vcc 3.35, flash size 2097152, free heap 43044
WiFi IP address 192.168.0.155
Signal strength -36dBm, channel 3, mode 802.11n, reconnections 0
Clock register 00002001
Socket states: 0 0 0 0 0 0 0 0

DWC Console

6/14/2023, 3:41:16 PM	Connection established
6/14/2023, 3:41:16 PM	Connection interrupted, attempting to reconnect...
6/14/2023, 3:41:08 PM	Emergency stop, attemping to reconnect...
6/14/2023, 3:41:07 PM	Connection established
6/14/2023, 3:41:07 PM	Connection interrupted, attempting to reconnect...
Operation failed (Reason: Service Unavailable)
6/14/2023, 3:41:04 PM	Connection established
6/14/2023, 3:41:04 PM	Connection interrupted, attempting to reconnect...
Operation failed (Reason: Service Unavailable)
6/14/2023, 3:41:01 PM	Connection established
6/14/2023, 3:41:01 PM	Connection interrupted, attempting to reconnect...
Operation failed (Reason: Service Unavailable)
6/14/2023, 3:40:53 PM	Connection established
6/14/2023, 3:40:53 PM	Connection interrupted, attempting to reconnect...
Operation failed (Reason: Service Unavailable)
6/14/2023, 3:40:50 PM	Connection established
6/14/2023, 3:40:50 PM	Connection interrupted, attempting to reconnect...
Operation failed (Reason: Service Unavailable)
6/14/2023, 3:40:46 PM	Auto tune starting phase 1, heating up
6/14/2023, 3:40:41 PM	M303 H0 S60 Y2
Auto tuning heater 0 using target temperature 60.0°C and PWM 0.85 - do not leave printer unattended

presto

Any updates?