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This new DIY 3D printer kit is a result of a vast market research and hours of development and engineering. It is an open source project, which means this is a versatile product that you can build upon and make it your own.
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Joined:10 Jul 2020, 14:54

Post by 7thcitizen » 10 Jul 2020, 15:03

Shortly after manually extruding filament on Extruder 1 successfully, E1 temp is showing -15*C when trying to manually extrude. Extruder 2 reaches temp without issue. Ran self check wizard and immediately received the error EC11. Checked connections as instructed in the operators manual, ensured everything is connected properly, rebooted device and still receive error EC11.

Joined:26 Jun 2020, 16:57

Re: EC11

Post by appoli » 22 Jul 2020, 12:46

Apologies for asking any silly questions/repeating what you said, just want to make sure that I understood everything correctly:

So, since you say you performed a manual extrusion on E1 then I assume you passed the initial self test the printer performs and when you manually extruded from E1 the printer detected the hotend getting up to temp.
If that’s the case I would probably recommend a few things & if not you can reply as such (I’m pretty new to all this, but the following seems logical):

1. In case you haven’t tried using the printer again since the error I would give it another go - I had an issue with the printer getting confused due to heat from the other extruder. Just needed to wait a bit and restart. This probably isn’t the case, but worth a shot.
2. When putting my printer together I noticed that one of the thermocouples wasn’t held in place very well. This could possibly be the same with yours - id double check to make sure the sensor is properly in the hot end.
3. Assuming the first two easy answers don’t work out the best bet would be to get a multimeter out and check the voltage being created by both temp sensors. See if they are the same at room temp (and can try heating them up too).
Another method could be to reverse the heater wiring and temp sensor wiring between the two extruders and see if the problem switches to E2. If it stays on E1 then the heater/sensor are probably fine.

Hope this helps

Joined:10 Jul 2020, 14:54

Re: EC11

Post by 7thcitizen » 31 Jul 2020, 11:23

Thanks for the great reply! Turns out one of the temp sensors was broken and once replaced it’s working well. I also had a thermocouple that was loose, made me think I was losing my mind when I was adjust nozzle height and leveling. As my luck usually goes, I believe I broke the temp sensor when I was tightening the thermocouple.

Joined:02 Jul 2020, 01:10

Re: EC11

Post by gannable » 13 Aug 2020, 00:53

For those who did not break their wires... yet...
One thing that I had read was that you should NOT tighten the thermalcouple as that will probably break the wires and it isn't needed except to keep the wires generally in place.

At the same time, I keep getting EC11 errors and I checked all the wires and everything was good. Flipping the wires between extruder 1 and extruder 2 made no difference... so figured it was the mother board.

Long story short, seems the connectors for the thermal coupler sensor connections are quite finicky at the motherboard. Make sure they are REALLY well seated as that fixed my problem. In case anybody else is fighting this same problem.

Joined:12 Dec 2017, 11:44

Re: EC11

Post by DomingosRodrigues » 01 Sep 2020, 12:39

Hello Gannable,

Let me just correct some of the information you provided.

You should hold the thermistor (we dont use Thermocouples in the B2X300) in place. But be careful not to over-tighten the wires as they are very sensitive as they have a PTFE line but internally have less than a mm of diameter. You should also use a metal washer to spread the pressure and avoid overstressing the wires when tightening.

Alternately you can use thermal epoxy to glue the sensor in place but I wouldn't recommend as it makes replacing the sensor almost impossible without replacing the whole hotend assembly.

Best regards
Domingos Rodrigues

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