UMO Hotend Wattage

[bob 0]

Anyone happen to know how many watts the Heater in the hotend of the UMO has?

[gr5 2,099]

I believe it's 25W nominal but typically it's as low as 18W.  Any wattage from 25W to 40W will work fine.  Going above 35W you may have to adjust your PID values a little bit to keep the temperature from oscillating.  I recommend 30 to 35W if you are buying a new one.

[bob 0]

Thanks for the info. I was hoping to go directly for the 40W since my current one maxes out at 230°c when using it for a longer duration. Unfortunately the ninja flex that I purchased needs 260°c to come out properly. 

 

In what way would I need to adjust the PID values?

[conny_g 251]

You can use the pid tune feature of the firmware, if UMO has that.

It will calm down the „curve“ and avoid overshoots, the print temp will be more stable.

[gr5 2,099]

UMO can easily get to 250C as I've printed ABS with it.  The problem is likely that your fan is blowing too much onto the nozzle (or bouncing off the glass and back to the nozzle).  Try setting the fan to 30% and try angling the shroud more downwards.

 

But yes you can also get a higher power heater.  Do you have a UMO with the 19V supply or a UMO+ with the 24V supply?  It matters when you choose a heater as the wattage depends on the voltage.  And if you get more than 35W you will probably have to adjust PID a little but it's not hard and we can explain how to do that if your temperature is oscillating too much.

[Dim3nsioneer 557]

Both UMO and UMO+ have a 40W heater cartridge but with different voltages.

[bob 0]

Yes, my fan probably blows on the nozzle too much...
I have the UMO which had a 19V power supply ( i've since replaced it) I. I am guessing you are referring to the PID in the Firmware?

Edited August 26, 2018 by bob

[gr5 2,099]

Is your printer still using 19V?  Or is it running 24V?  Hopefully 19V because if you switch to 24V then that changes the wattage of your heaters and the voltage regulator will get quite hot as well.

 

So you should be able to control PID from the menus.  If not you can certainly change them using gcodes.  There's a gcode to autotune the PID.  There's one to set the PID, one to read back the PID and one to save into eeprom (permanent memory) all settings including latest PID values.

 

But don't worry about PID unless your heater temp is oscillating (typically it oscillates with roughly 20 to 100 second period) badly.  Such as more than 4C error for hours.

[bob 0]

My printer is using 19.5V, since that the lowest I could adjust the Chinese 24V power supply with out using extra electronics..But no, am not have those kinds of issues...yet... Just ordered new heads with 12V 40W hearters but in retrospect i probably should have gone with 24Vs and mosfets instead...