Bed MOSFET melting adjacent connector January 08, 2017 06:43PM |
Registered: 7 years ago Posts: 4 |
Re: Bed MOSFET melting adjacent connector January 09, 2017 04:15AM |
Registered: 8 years ago Posts: 5,232 |
Re: Bed MOSFET melting adjacent connector January 09, 2017 10:39AM |
Registered: 7 years ago Posts: 4 |
Quote
o_lampe
P55 would work so-so, when the 5V supply from the arduino is stable. When it drops to 4.x V ( due to other components on the 5V rail like graphic controllers ) the MOSfet gets really hot, because it won't switch open fully.
Re: Bed MOSFET melting adjacent connector January 09, 2017 04:37PM |
Registered: 8 years ago Posts: 5,232 |
Re: Bed MOSFET melting adjacent connector January 10, 2017 09:12AM |
Registered: 7 years ago Posts: 4 |
Quote
o_lampe
If you want to use an external 5V supply connected to anything else than USB, you have to modify the RAMPS board. ( Disconnect D1, IIRC )
Sometimes people have to do this MOD, because they want to use 5V servos powered by RAMPS.
OTOH, a powerful USB PSU doesn't help, as soon as you connect 12V to the RAMPS. Then the onboard 5V regulator on the Arduino will be used and the USB PSU is cut off. ( without the D1-mod )
Re: Bed MOSFET melting adjacent connector January 10, 2017 02:46PM |
Registered: 8 years ago Posts: 5,232 |
Re: Bed MOSFET melting adjacent connector January 11, 2017 04:47PM |
Registered: 7 years ago Posts: 4 |
Quote
o_lampe
Yes, that's actually the same as using 12V from the RAMPS. It only feeds the weak onboard regulator from Arduino.
Re: Bed MOSFET melting adjacent connector January 12, 2017 03:09AM |
Registered: 8 years ago Posts: 5,232 |