Avoid Bed pre-heat crashing MKS Gen L v1.0 board ?

HI,

My flsun i3 plus works well but has an annoying habit of randomly rebooting as the bed heats up before printing starts.

What would you do?

I am thinking this might be momentary power shortage to the arduino mega. So if I added a biggish - say 1000uF capacitor across GND and 5V somewhere (e.g. near USB connector) would that be likely to work?

The MKS Gen L v1.0 board seems to be RAMPS 1.4 and arduino mega combined on one board.

I have a spare mosfet board - would running the hotbed using this on the same power supply help? If separate power needed I could use an old PC power supply - would you use this as the main power or the hotbed power.I assume the hotbed uses the most power.

Thanks for any help and suggestions.

M

If you see a brownout during bed-heating, it's most likely caused by the polyfuse tripping. ( Those curry-colored flat squares..) You can use a fan to cool the controller ( recommended anyway ) or replace these fuses with others.
Using the external MOSFET will also work.

Edited 1 time(s). Last edit at 07/25/2018 01:47PM by o_lampe.

Well the mosfet installed and first print just fine. No crashes.

Second print and I found the power supply making a fast ticking noise and all was dead, including the power supply - though no visible signs of damage inside or out.

Replaced with an old PC power supply and all sprang to life and seems good so far after a couple of prints....