Problem with heaters? Or bug?

bojan

Hi,

After years of using Repetier host with my machine (repetier f/w version 1.0.3), now I have a strange problem.

After _15minutes into printing, the whole thing stops with error in red window (something like "sensors disconnected from heaters, continue with "9999"). And I couldn't continue, I had to abort the session and start again from the beginning. Sometimes the new session is successful, but most of the times it ends like the previous one.

On temperature logs I can't see any problem - everything behaves as it should, and I checked all connections.. no obvious problems found there either.

Anyone had similar issue and suggestion what to do next?

I was even thinking of replacing the RAMPS1.4 and/or MEGA board with new ones..

bojan

Also, I disabled cooling in Slic3, but it did not have an effect, fan keeps switching ON on printer..

I did not notice this kind of behavior on previous version of Host...

Repetier

This is a printer firmware/printe rissue and has nothing to do with host or connection problems.

Modern firmwares check measured temperature versus expected response and as soon as they detect it they stop heaters with exactly that message. See log window for exact details when it happens. Typical reason is a broken sensor cable - especially at the beginning it might report good values most of the time, but at some positions where the cable is on most strain close to break it causes a disconnect triggering the error.

bojan

Thank you for quick reply and suggestion :-)

Yes, originally I had the problem with sensor cable, I suspected connectors (header on RAMPS1.4 or sensor, so I replaced sensor + cable (and added connector at sensor so I can replace sensor again in case of fault without removing cable).. but there was no strain on those places at all).. the behavior was different then, on the temp log it was clearly visible that something was very wrong (reported temperature was all over the place and completely different from actual temperature, so I replaced the whole printing head. Next time when this error happens. I will post the log file.

bojan

OK, here it is again.. after ₁₅ min of printing, same error, relevant part of log is below. There was nothing indicating this shown on graph.

I did nothing, just restarted the job and it went through OK.

Also, despite cooling disabled ( Slc3 override), it was still on while printing...

> 11:58:38.234 : DebugLevel:14
> 11:58:38.243 : Error:One heater seems decoupled from thermistor - disabling all for

safety!
> 11:58:38.246 : Error:Temp. raised to slow. Rise = -2.35 after 301018 ms
> 11:58:38.251 : Disabling all heaters due to detected sensor defect.
> 11:58:38.251 : DebugLevel:14
> 11:58:38.266 : RequestStop:
> 11:58:38.648 : T:234.62 /0 B:95.63 /0 DB:2 B@:0 @:0
> 11:58:39.734 : T:234.87 /0 B:95.63 /0 DB:2 B@:0 @:0
> 11:58:40.163 : busy:processing
> 11:58:40.836 : T:234.87 /0 B:95.56 /0 DB:2 B@:0 @:0
> 11:58:41.442 : TargetExtr0:0
> 11:58:41.446 : T:234.87 /0 B:95.56 /0 DB:2 B@:0 @:0
> 11:58:41.490 : fatal:Heater/sensor error - Printer stopped and heaters disabled due to

this error. Fix error and restart with M999.
> 11:58:41.493 : fatal:Heater/sensor error - Printer stopped and heaters disabled due to

this error. Fix error and restart with M999.
> 11:58:41.493 : ok 15453
< 11:58:41.495 : N15454 M104 T0 S032
> 11:58:41.511 : fatal:Heater/sensor error - Printer stopped and heaters disabled due to

this error. Fix error and restart with M999.
> 11:58:41.511 : ok 15454
< 11:58:41.513 : N15455 M140 S0101
> 11:58:41.527 : fatal:Heater/sensor error - Printer stopped and heaters disabled due to

this error. Fix error and restart with M999.
> 11:58:41.527 : ok 15455
< 11:58:41.528 : N15456 G1 X0 Y-10 F480092
> 11:58:41.546 : fatal:Heater/sensor error - Printer stopped and heaters disabled due to

this error. Fix error and restart with M999.
> 11:58:41.546 : ok 15456
< 11:58:41.546 : N15457 M8429
> 11:58:41.560 : fatal:Heater/sensor error - Printer stopped and heaters disabled due to

this error. Fix error and restart with M999.

bojan

Last printer head temp reported is 233.85° which seems to be OK (much deeper drop occurs when cooling fan is started. BTW, I sorted cooling issue).

> 11:58:37.540 : T:233.85 /235 B:95.63 /98 B@:255 @:20

Repetier

> 11:58:38.243 : Error:One heater seems decoupled from thermistor - disabling all for

safety!
> 11:58:38.246 : Error:Temp. raised to slow. Rise = -2.35 after 301018 ms
> 11:58:38.251 : Disabling all heaters due to detected sensor defect.

Is the critical part where firmware disabled heaters. So still firmware issue. It is one where timeout is 300s = 5min. So I think we are talking about your bed, extruders have normally a lower setting. Raised to slow is in heat up phase until target- PID_CONTROL_RANGE which is normally 20 so should not cause it here. Are you using 1.0.5 dev firmware with update lately? We added a own range for bed recently named PID_CONTROL_RANGE_BED which is set to PID_CONTROL_RANG if not set explicitly. Because if you were at 95.63°C at that time you should be in hold temperature mode so that error would not appear at that temperature.

bojan

Thank you for your reply. I am using 1.0.3 f/w.

I will update to latest and test.

bojan

It may also be that my room temperature dropped or was too low because I opened the window to ventilate (fumes from ABS)... Also bed heater capacity may be close to upper limit (it is very hard to reach above 100°C.. so I keep it at 98°).

I will try couple of things in that direction and report.

bojan

BTW, before attempting anything "drastic", can change something in EEPROM settings below?

>Bed Preheat temp.</epr><epr pos="106" type="0" value="0"
>Bed Heat Manager</epr><epr pos="107" type="0" value="255"
>Bed PID drive max</epr><epr pos="124" type="0" value="80"
>Bed PID drive min</epr><epr pos="108" type="3" value="196.000"
>Bed PID P-gain</epr><epr pos="112" type="3" value="33.000"
>Bed PID I-gain</epr><epr pos="116" type="3" value="290.000"
>Bed PID D-gain</epr><epr pos="120" type="0" value="255"
>Bed PID max value</epr><epr pos="1020" type="0" value="1"

bojan

It was actually like below, I posted changed value ("255")

>Bed Heat Manager</epr><epr pos="107" type="0" value="230"

bojan

Despite having "255" for bed output range in EEPROM,

>Bed Heat Manager</epr><epr pos="107" type="0" value="255"

I have the error again:

> 16:26:31.621 : DebugLevel:14
> 16:26:31.630 : Error:One heater seems decoupled from thermistor - disabling all for safety!
> 16:26:31.634 : Error:Temp. raised to slow. Rise = -5.29 after 301017 ms
> 16:26:31.638 : Disabling all heaters due to detected sensor defect.
> 16:26:31.638 : DebugLevel:14
> 16:26:31.646 : RequestStop:
> 16:26:32.236 : T:235.13 /0 B:92.70 /0 DB:2 B@:0 @:0
> 16:26:33.125 : TargetExtr0:0
> 16:26:33.129 : T:235.13 /0 B:92.70 /0 DB:2 B@:0 @:0
> 16:26:33.172 : fatal:Heater/sensor error - Printer stopped and heaters disabled due to this error. Fix error and restart with M999.

bojan

I suspect fan is the culprit, it is switching ON despite being disabled in slicer (I thought I sorted it out bu didn't, apparently).

I can see on tempo graph that bed temperature is dropping at the same time fan is switched ON.

Repetier

What is your PID_CONTROL_RANGE value?

It is a known effect that fans can reduce temperature for a while. If heaters have enough power they catch up sooner or later. Normally the rang eis 20°C so when target is 100 at 80°C it would switch to hold temperature mode, which did not happen also you were at 93°C so I think that value is too low. Once holding you get a other like "Error:Could not hold temperature...". So once you reach 80°C with variance 20 only a drop down below 80 would trigger the message.

bojan

In configuration.h I found the following value:

#define PID_CONTROL_RANGE 20

My bed temperature is set to 98°C, and error happens at _93°.. so it doesn't make sense to me.

bojan

The bed definitions in configuration.h:

#define HAVE_HEATED_BED 0
#define HEATED_BED_MAX_TEMP 120
#define SKIP_M190_IF_WITHIN 3
#define HEATED_BED_SENSOR_TYPE 1
#define HEATED_BED_SENSOR_PIN TEMP_1_PIN
#define HEATED_BED_HEATER_PIN HEATER_1_PIN
#define HEATED_BED_SET_INTERVAL 5000
#define HEATED_BED_HEAT_MANAGER 0
#define HEATED_BED_PID_INTEGRAL_DRIVE_MAX 255
#define HEATED_BED_PID_INTEGRAL_DRIVE_MIN 80
#define HEATED_BED_PID_PGAIN 196
#define HEATED_BED_PID_IGAIN 33
#define HEATED_BED_PID_DGAIN 290
#define HEATED_BED_PID_MAX 255
#define MIN_EXTRUDER_TEMP 150
#define MAXTEMP 275
#define MIN_DEFECT_TEMPERATURE -10
#define MAX_DEFECT_TEMPERATURE 290

Repetier

I see you use heat manager 0 (bang bang) - here the var range has no effect. So it still makes sense. It is expected that while on temperture rises and while off temperature falls. So in this case you should increase DECOUPLING_TEST_MIN_TEMP_RISE_BED such that even if fan turns on in that interval the bed catches up heating. So if you need 6 minutes to reach the temperature before turning on fan increase that to 6 minutes (6601000).

bojan

Aaa, OK. thank you for this suggestion. I will try and report.

Also, I will try to modify the cooling fan nozzle, to concentrate the air flow to smaller area immediately around printing head.