Upgraded E3D v6 - High Ambient Nozzle Temp

[GeekStreetSolutions]

I recently upgraded my Rostock Max v2's e3d v6 thermistor from the old screw in m3 thermistor to the newer block and sock upgrade kit with the thermistor cartridge. After installing it and configuring it with the Repetier 092 my screen was jumbled and I could not get it displaying properly and also could not connect in MatterControl so I switched the firmware back to Repetier 091 and then made the changes accounting for the length values of my ball and socket arm kit (as opposed to the old laser cut carriages and old arms) from SeeMeCNC as well as following e3d's Instructions to configure the thermistor type:

Use thermistor definition number 8:

#define EXT0_TEMPSENSOR_TYPE 8

I noticed some problems after this upgrade:

• 1. As soon as I turn on the printer the ambient temp of the nozzle displays around 101.3c. This also causes the nozzle fan to come on which usually would only go on if the nozzle was above 50c. With the old thermistor, both the bed and nozzle read around 27c
  2. The thermistor seemed to be working as the printer was not displaying def and the nozzle temp on the LCD was fluctuating ±.1c

3. Stupidly I then decided to go ahead with the PID tuning despite this and shortly after starting the tuning process I saw some smoke coming from the hardened steel nozzle I had just installed. Luckily I think I caught this in time and was able to turn off and on the printer stopping PID tuning and started cooling it down. After bringing the temp back down I turned the printer back on and saw it still was displaying around 101.3 ±.1c.
4. I then wanted to know if it was a loose connection so I examined all the wiring and found no faults (If there would be a fault why would the thermistor even be displaying a temp instead of def?). I got my hot air gun and slowly heated the block until the temperature on the LCD changed. It had started changing normally starting at 101.3c so that was good.

What I don't understand is why it is displaying such a high ambient temp and if this is a physical defect (bad thermistor or wiring?) or did I just misconfigure the firmware configuration.h file. What should I do to fix this issue? I will be sending this same text to e3d and update this post with any new info.

[Xenocrates]

I would check the resistance of the thermistor wiring at a few points, and find a thermocouple to look at your actual temperature with. Most likely you have a partial short somewhere, meaning a small solder bridge, or some other relatively high resistance short. Also, the smoke from the hardened steel nozzle is normal, and due to burning off the residue from machining and hardening. I would soak it in acetone to degrease it if you don't want a repeat performance.

If you have a resistance of ~100K ohms at the rambo terminals, it's a config issue. Most likely, it's a wiring issue (if the resistance is substantially less).