Heatbed below 60 degrees Celsius restarts printer

[kupfeli 9]

Hi!

 

i have a brand new Ultimaker 2+ Connect and whenever I set the bed temperature below 60 degrees celsius and start a print, the preheating process starts and after a few seconds the printer shuts down and reboots.

So, basically I cant set the heatbed to temperatures lower than 60 degrees celsius 😞

 

Above 60 degrees no problems at all.

 

Anyone recognizes this problem and might know what to do?

 

Thanks in advance!

Edited May 17, 2021 by kupfeli
Small correction/improvement

[gr5 2,178]

I'd replace the power supply.  If it's still under warranty I'd ask for a power supply from the reseller.

 

Most metals, including the one used in the Ultimaker heated bed, have a higher resistance as the temp gets higher so it uses less power.  Your bed heater uses more power at lower temps.  But not enough to cause the power brick to fail until other things come on (servos).

 

I've seen these power bricks fail many times - they are all a little different.  They have sophisticated computers that detect over current, over voltage, over heating.  They typically turn off the 24V power only for a portion of a second which causes the computers in the printer to reboot.

 

Another thing to try - check the resistance on the X and Y axes.  Higher resitance uses more power by the steppers (I used to think that wasn't true but I proved by putting a current meter on the printer and fighting against the print head movement).  Maybe add a drop of oil to each of the 4 thick and 2 thin rods in the gantry.

 

But basically I'd get a new power brick.  Around $100 on ebay/amazon/etc

 

I'm not sure exactly which power brick the UM2+C uses.  Probably this one:

GST220A24-R7B

 

If you have the above one, the below one is almost identical but can put out about 20% more power in my experience (even though the specs written on the supply are identical):
GS220A24-R7B

 

Ultimaker doesn't like it because it has fewer safety features and doesn't pass CE I think.  Maybe that's the reason.

 

[fbrc8-erin 274]

@kupfeli the bed isn't intended for printing below 60C as far as I am aware. @Szahari can explain in more detail.

I have found a work around: by starting a print with the temperature at 60 C, aborting it, and then starting your lower temperature print while the bed is still warm.

 

What are you printing that needs to be done at below 60 bed temperature? I usually find 60C to be a great starting point.

[kupfeli 9]

These replies help me alot!! Thank you very much @gr5 and @fbrc8-erin

 

I indeed have the GST power supply.

 

I wanted to experiment with lower bed temperatures for a specific type of PLA.

 

I try the workaround and will also ask my seller for a new power supply, because the printer is 1 month old.

[fbrc8-erin 274]

GST is the correct power supply for the machine; GSS have not been used since 2016. 

The issue you're describing is something we were able to replicate in our office using our UM2C; it's expected behavior for the printer as far as I can tell, as it's not intended to print with a below 60C bed. @Szahari may be able to explain in more detail.

[kupfeli 9]

@fbrc8-erin thank you very much! I will also tell my reseller this, as presumably they are not aware of this.

 

I am looking forward to the exact explanation from @Szahari if he/she would be willing to explain.