HE280 won't heat up even though LED is on.

[kkostolich]

This is my first post for help so I hope this is the appropriate place. I also posted this in the Rostock Max V3 area.

I had the orange wire in my whip break off from the 8 pin connector one night while printing a part on my RS Max v3. This resulted in my HE280 shutting down while the printer continued to think it was printing that evening. So I bought a new accelerometer (rev 6) board and built a new HE280 out of parts I was holding in reserve for repairs should they stop selling stuff for the HE280. I have a new whip, a completely new HE280 with the new heater block and the new thermistor. Everything in the new HE280 is brand new.

After finishing the HE280 I did a test run to make sure it worked. It in fact heated up beautifully, but only two times. I tried it a third time and it will no longer heat up even though the red LED on the accelerometer board turns on. My original hotend wont heat up past 190c and my new one will not longer heat up. I am not an expert at this but I am thinking that maybe my RAMBO board shorted when the wire broke, but I have no idea. I have done nothing to the RAMBO other than connect a new whip.

Any help that you can provide would be greatly appreciated. I am stuck at this point. Could my new Rev 6 board also be bad? I mean it heated up beautifully twice. I haven't replaced the small ceramic fuse in my RAMBO yet because the other hotend still kind of heats up. Thank you in advance for taking to time to read this and possibly help me out.

~Ken

[geneb]

Does your HE280 have the thermal fuse installed on it? If so, you might want to check to make sure that's not blown. If the little LED on the HE280 PCB lights up, that says that the RAMBo is working just fine and there's an issue between the PCB and the heater cartridge.

Does your old hot end use two resistors as heating elements? If so, it's likely one is blown. The two resistors can be replaced by a single heater cartridge.

g.

[kkostolich]

Thank you for your reply, I really appreciate the help.

Yes, my HE280 does have a thermal fuse. My set up on both of my HE280's is the Rev6 board with the thermal fuse connected to the heater cartridge inserted into the new style heater block with the new style thermistor. I only have one thermal resister per hot end.

Am I able to remove the thermal fuse all together? So I will need to just figure out a way to extend the wires from my heater cartridge to the PCB? I just read the below information on the parts page. Will this work for the main thermal fuse? The one that connects the PCB to the heater cartridge?

"Your RAMBo controlled SeeMeCNC printer should be updated with "firmware" located on github.com/seemecnc, then the thermal fuse is not necessary and can be bypassed".

https://seemecnc.dozuki.com/Guide/RAMBo ... 50?lang=en

Thank you again for your help Gene! You are certainly a 3D Jedi!

~Ken

[geneb]

Have you determined that the thermal fuse is bad? As for doing mods to skip the fuse, I would contact support about that. ([email protected])

g.

[kkostolich]

Yes Sir, you are correct with your diagnosis. I just pulled it all apart and tested the fuse with my continuity function on my multimeter, and it is bad. Would you have any idea why it blew and how I can prevent that in the future? Could that broken orange wire on my whip have damaged something further up the chain? I mean, both hotends are having problems out of the blue. But it's the newest hotend that has me confused because all of the parts were new.

I will also contact the support group about the mod. It that is an option then I would like to upgrade. This is an awesome machine and I want to keep it for a long time.

Either way, you really did help me out and I greatly appreciate your time. I know you don't have to do this, but I thank you for helping a guy you have never met.

Ken

[geneb]

You're quite welcome! I'm happy to help. Gotta keep those nasty bed-flinging cartesianistas at bay.

Typically the fuse will blow if the fan attached to the heat sink on the hot end isn't running. The orange wire is for the layer fans. I don't know if it shorting against something else could have been your problem, sorry!

g.