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All of the sudden my bed is taking a long time to heat up. The light flickers now instead of showing as solid when it's heating. I have a feeling it's the power supply going bad, but I'm not sure how to confirm this. It's been acting weird lately. Like causing a delay to turn off or on when i use the direct switch in the back. Also i'm not sure if i just never noticed this but when i move my skates and the power is off it causes my LCD to come on. Is this just residual power I'm creating with my motors to power on the board? Anyways i've been sitting here for 30min and it's only upto 43.4c. My E3D v6 has no problem getting upto 220 as usual. I checked all my wires and everything seems fine. Reading other posts it was suggested to check the power on the onyx at the solder points and the input and output power on the RAMBO on and off. How do i tell if it's the power supply or something else?



Also, i just spent two days setting up the air struder and as soon as i'm ready to test it, this happens. Why do our printers love to abuse us so much? I feel like this always happens. So frustrating


Solution: Somehow how heated bad MAX PID got changed to 40 which limited the power going out. Once i set it back to 255 everything was back to normal. I would be cautious when editing your EEPROM settings with mattercontrol.

I checked the input power from the power supply on the bundle of wires and i'm getting around 11.6v i checked the screws for the heated bed and I;m getting around 1.7v when the bed is supposed to be heating up. I swapped out the two ceramic fuses and the large fuse so it can't be a blown fuse. Whats the deal?

A fuse either works or doesn't, it would take some very odd circumstances for a fuse to cause a voltage drop like you're measuring.

It's much more likely that you've got a loose wiring connection somewhere. Test for continuity between the terminal on your Rambo and the solder pad on the bed itself. Tighten the screws on the terminal block, too.

If it's not a wiring SNAFU, it possible that the MOSFET on your board is bad?

Not sure why my last post didn't show up.

I don't think it could be wiring from the Rambo to the onyx because that power output is only around 2v max. It has to be either the black and yellow psu wires not making a good connection or an issue with the Rambo.

Take a close look at the RAMBo screw terminals. Very low voltage at the heated bed output terminals could be a sign of terminals overheating. Look for deformation of the plastic housing, discoloration of the metal terminals, or charring/blistering of the circuit board. They tend to occur in that order.

Earthbound wrote:Take a close look at the RAMBo screw terminals. Very low voltage at the heated bed output terminals could be a sign of terminals overheating. Look for deformation of the plastic housing, discoloration of the metal terminals, or charring/blistering of the circuit board. They tend to occur in that order.

Thanks for the suggestion I'll take a closer look. I didn't see anything different during my troubleshooting but I'll give it a try with more light.

My heated bed max PID value was the issue...
Like the 100's of times i had done before i was calibrating my printer after some mods and editing the horizontal radius and i guess somehow the heated bed max pid got changed to 40 from 255. I could understand if that number got changed to something similar to the original value like 25 or 55 or some relation to my horizontal radius value. That could at least be explained by human error but it isn't close to either. So where did the 40 come from???? I guess only mattercontrol or my RAMBO knows. I've taken screenshots of all my eeprom values in case something like this happens again. I'm using OSX with mattercontrol btw. I've noticed issues with it before as it's not too stable on OSX.

Thanks to everyone who took the time to respond and offer advice.

staticbunny wrote:My heated bed max PID value was the issue...
Like the 100's of times i had done before i was calibrating my printer after some mods and editing the horizontal radius and i guess somehow the heated bed max pid got changed to 40 from 255. I could understand if that number got changed to something similar to the original value like 25 or 55 or some relation to my horizontal radius value. That could at least be explained by human error but it isn't close to either. So where did the 40 come from???? I guess only mattercontrol or my RAMBO knows. I've taken screenshots of all my eeprom values in case something like this happens again. I'm using OSX with mattercontrol btw. I've noticed issues with it before as it's not too stable on OSX.

Thanks to everyone who took the time to respond and offer advice.

I noticed that when I updated MC to 1.2.3, all of a sudden, the layer fan would turn on during an ABS print. I hadn't changed any settings in the filament profiles but somehow they changed. So it's not just a mystery on an OSX machine. This is a Windows 7 PC.