Heated bed

[cimball]

I have a Printrbot Jr v2 And i am trying to work the heated bed. when i am using cura i can start the preheat process but it only get up a couple of degrees before the machine shuts down and i lose connection. I understand that people have had similar problems to this in the past however, none had the same issue i am having.

Things i have done:
checked for short on the bed and as well as the board
ensured the connections are solid and intact

I would love the help and I hope someone has my answer, thank you.

[novice]

Wonder if something in the power supply is dropping out under load causing loss of power ?? Are you able to switch power supplies or if not place a voltmeter across the leads from the power supply to monitor voltage when this occurs?

[cimball]

One thing I did notice about the power supply is that the molex port doesn’t have the 5v pins in it, is that standard with all of them?

And that could be an issue and I’ll see if I can get a better psu.

[cimball]

[RetireeJay]

The Printrboard only uses 12V from the power supply. It creates lower voltages on-board as needed. The correct cable to use from an ATX power supply has only yellow and black wires, for +12V and ground respectively. There are many cables coming out of an ATX supply, but you can ignore the rest of them. Some printer owners use other types of supply (laptop brick, "LED" supply, etc.) The bottom line is you need 12V. When running a heated bed, you need to have approx 350 watt (or about 20 amp) capability on the 12V supply).