Thank you gr5.
I've tried it and got it working now.
When I uploaded the firmware to the UM with Arduino IDE, the ulticontroller keeps blanc serveral times
when powered on.
At the end I've got it working.
Regards,
Harold
Thank you gr5.
I've tried it and got it working now.
When I uploaded the firmware to the UM with Arduino IDE, the ulticontroller keeps blanc serveral times
when powered on.
At the end I've got it working.
Regards,
Harold
Daid, when will be FW again online ?
I tried and my ulticontroller also goes blank, but mine doesn't recover. Did you change anything after your controller went blank?
would you mind sharing the .hex file?
Hello spiruline,
When my UM controller went blanc, I've installed the default firmware back with Cura.
Below the link of the hex file I use now:
https://dl.dropboxusercontent.com/u/1911369/Shared%20Files/UM_1.5.7_with_heatbed_firmware.zip
I cannot give any guarantee that it will work on your UM, but if you have a 'regular' 100K thermistor and a PCB version of 1.5.7, it should work.
Let me know if it did.
Regards,
Harold
Hi Harold,
Thank you very much for sending the .hex file. I feel closer to the solution as I can see heatbed setting on the ulticontroller screen now.
But I have tested but I get a MAX HEAT BED TEMP ERROR from the start. I am using a "normal" 100k thermistor (bought over the counter in a electronics shop). I am not after very accurate temperature control. I just want the Ultimaker board to control a relay that powers the heatbed and keep the temperature within a reasonable range. I checked the resistance of the thermistors and it is about 100k at room temperature.
The Heat bed will be powered with a 20A external power unit and switched on and off by the relay.
I have soldered the 4,7 R4 resistor to the board.
Any idea why I get the MAX TEMP error?
Any idea why
Hello spiruline,
I think you need to twist the wires of your thermistor on the PCB board.
I also control the heatbed by the pcb with a relay.
Regards,
Harold
I am going try swaping the wires, but I thought that thermistors worked like a regular resistor (but changing resistance with temperature) where polarity doesn't matter...
The polarity does not matter.
Did you install the 4.7K resistor also?
If not, read about it here:
http://wiki.ultimaker.com/Heated_Bed
Thank you for the tips,
I am one step closer, but not quite there...
I double checked the 4,7K resistor and it was poorly soldered, I fix that and the MAX TEMP error doesn't show anymore.
BUT now I get no temperature reading, just 0. And if I try to set any temperature in the ulticontroler there is no response from the HEATED_BED connector. The thermistor gives about a 130 K reading at room temperature.
I am connecting the relay directly to the HEATED_BED connector. I am not connecting my secondary power unit and heated bed yet. I just want to see the relay being activated by the Ultimaker PCB. The red LED associated to the HEATED_BED connector doesn't lit at all like the nozzle heater does.
Am I missing something else?
Do I understand you correctly, you do see a room temperature on the UM controller, measured by the thermistor?
If you do, check if you got the relay connected the right way, see the schematics below (also the + and - from the terminal block):
Regards,
Harold
No, I don't see a room temperature on the UM controller, The UM reads 0. (I got the 130 k room temperature reading connecting the multi-tester to the thermistor).
I am going to rewire the thermistor connector, just in case there is a bad contact. I´ll let you know how it goes.
Even if I do not connect anything to the HEAT_BED connector, I should see the RED LED flashing, correct?
I don’t know about the red light, I didn’t looked at it....
There must be something wrong with the thermistor or the connectors.
I keep trying to make it work without success.
I have checked over and over the Thermistor connection and everything is well connected but the temperature reading keeps showing 0.
I have checked how the resistance of the thermistor varies with temperature changes using a multi tester, so the thermistor is working correctly but the Ultimaker is not detecting it. The multi tester shows about 100k at room temperature an decreases as it warms up.
anyone has any ideas I could try to make it work ?
So I believe the circuit is a simple voltage divider with a 4.7k resistor and 5v. If the thermistor is 100k then the voltage is
5v times r1/(r1+r2) where r1=4700 and r2=100000 or the other way around.
So with the ultimachine on, measure the voltage on both sides of the thermistor. One side should either by 0v or 5v and the other side should make sense with the above formula.
I have checked that and one side of the thermistor was 5v but the other one was 0.
Why could this be happening?
That's not good. One side should be about 4.7/104.7 or about 5% away. In
other words one side should be around 4.75 or the other side should be .25v.
I would have expected the high side to be at 4.75. If it is indeed 5V then
the 4.7K resistor seems to be a short circuit. Or at least much less than
4.7K ohms. Maybe you should measure that resistor (with the thermister
disconnected).
Bingooooooo !!!!
Thank you so much for your patience with my novice clumsiness. Your last post made me think about the resistor, I checked again and I realized it was 4,7 ohm instead of 4,7 K.
Now everything seems to be working fine and the board controls the relay according to temperature. I just have to make some hardware adjustments, like lowering the Z stop switch to fit the taller heating bed and I´ll be ready to try ABS printing
Recommended Posts
gr5 2,224
1) I don't think there is such as thing as a regular 100k resistor. Do you have the EPCOS one?
Just try it. Get the erikZalm source code. edit configuration.h (that is the longest step by far). configuration.h is very very well commented. Just read it and edit it.
Then download the arduino IDE. Then follow directions. I think it was a total of maybe 4 mouse clicks to build the thing. It's really not a big deal. The instructions at the bottom of this page look pretty good:
http://reprap.org/wiki/Marlin
Link to post
Share on other sites