LED contol work around help

I just started with 3d printing/Arduino universe so I am not sure how to approach this. I recently purchased a Folder Tech 2020 Prusa i3. I am trying to print with ABS and I found that I could not get my heat bed above 67c. I read to accomidate this I should increase my voltage to up to 14 and I should insulate the bed with some cardboard or something. I put the cardboard down and stepped the voltage up to 13.5v from 12v. I am getting in the mid 70's now on the heat bed but still not making it to the 100 mark.

One thing I had read was that when doing this It would mess up the LED attachment. I have the RepRapDiscount Smart Controller. I would like to use it but now I am afraid to plug it in because I dont want to mess it up. Searching around I am still unclear on what to do to make sure its safe to plug in the LED board.

Any help would be most appreciated.

I run my Ramps with 13.5V for a few month now, using the same discount LCD without problems.
I don´t know, how this would help getting the bed to 100°C?
-Olaf

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o_lampe
I run my Ramps with 13.5V for a few month now, using the same discount LCD without problems.
I don´t know, how this would help getting the bed to 100°C?
-Olaf

apparently 12v isnt enough to get my heat bed up to temp. So i was concerned that by upping the voltage I would destroy the LCD as I have read warnings to in other posts. Glad to see that you haven't suffered any side effects as a result of the voltage increase. I just dont know enough about these things yet. For all I know, those warnings I have read could not even apply to what I am doing. Just want to be cautious and not destroy things that work.

I think the LCD is powered by the 5V rail on the ramps... Turning up the Volts will make the bed hotter, really you should get an external PSU for the bed, a cheap Micro ATX Power Supply be will be enough, i don't like the idea of powering the printer and the bed from the same PSU, it could cause problems.

Whats the resistance of the heated bed? Whats the spec of the PSU you are using?

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eatumup
apparently 12v isnt enough to get my heat bed up to temp. So i was concerned that by upping the voltage I would destroy the LCD as I have read warnings to in other posts.

You won't destroy the LCD, but you may overheat the 5V regulator on the Arduino. A workaround is to disconnect the LCD backlight anode from +5V and connect it through a resistor to +12v instead. A 180 ohm 0.6W resistor should be about right for a 12864 display.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

Thank you all for the suggestions. I kind of like the idea of an independent psu for the heat bed. Im running a 360w 30A PSU. The heat bed resistance I don't know. Its the one that came with my FoldgerTech 2020 prusa i3. If I did run a seperate Power supply for the bed, could I run it though the same ramps board? Im not really sure how the Ramps passes power from the PSU to just the heat bed or if it passes it along to other systems.

If the 5v regulator was overheated would I lose anything other than the LCD back light?

If the 5V regulator on the Arduino overheats, it will eventually fail. Before that, the voltage on the 5V rail will fall, which will cause the mosfets to run hotter and possibly fail, in particular the heated bed mosfet.

Yes it's possible to use a separate PSU to power the heated bed with a RAMPS. This is one way of using a higher voltage PSU with the heated bed than the voltage that the rest of the Arduino/RAMPS can take.

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Large delta printer [miscsolutions.wordpress.com], E3D tool changer, Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].

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eatumup
Thank you all for the suggestions. I kind of like the idea of an independent psu for the heat bed. Im running a 360w 30A PSU. The heat bed resistance I don't know. Its the one that came with my FoldgerTech 2020 prusa i3. If I did run a seperate Power supply for the bed, could I run it though the same ramps board? Im not really sure how the Ramps passes power from the PSU to just the heat bed or if it passes it along to other systems.

If the 5v regulator was overheated would I lose anything other than the LCD back light?

You can run it via the RAMPS but you need an external relay, they can be bought fairly cheap. Read this link to understand it a bit more:

[www.youmagine.com]

Note, you don't have to make one, they are available to buy, but read the link to understand what you are trying to do.

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xelad

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eatumup
Thank you all for the suggestions. I kind of like the idea of an independent psu for the heat bed. Im running a 360w 30A PSU. The heat bed resistance I don't know. Its the one that came with my FoldgerTech 2020 prusa i3. If I did run a seperate Power supply for the bed, could I run it though the same ramps board? Im not really sure how the Ramps passes power from the PSU to just the heat bed or if it passes it along to other systems.

If the 5v regulator was overheated would I lose anything other than the LCD back light?

You can run it via the RAMPS but you need an external relay, they can be bought fairly cheap. Read this link to understand it a bit more:

[www.youmagine.com]

Note, you don't have to make one, they are available to buy, but read the link to understand what you are trying to do.

Most Excellent. Thank you very much