Burnt out RAMPS 1.4???

I am now on my 4th RAMPS in 1 week and have no idea what is causing the problem and cannot afford to keep on doing this. It was working fine for a month or so and then the heater failed to heat the extruder. We then pulled the RAMPS off and saw that the bottom track connecting the wire to the MOSFET had burnt out. This then happened on 3 other RAMPS boards as well. On the first board (green in the picture) we attempted to swap out the MOSFET but that had not worked. There was too much damage to the board.

flickr link

The boards are from different suppliers, (2) reprapdiscount, lulzbot and ultibots?.


Bot type + setup
Mandel
Marlin firmware
Jhead extruder
4 stepper motors
Heated build platform
240w power supply
Software: Slic3r & Pronterface

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Edited 1 time(s). Last edit at 07/04/2013 08:11AM by coreformula.

So then you concluded it's not the RAMPS boards that are the problem.


So what heater is it that is causing the MOSFET's to fail? The extruder heater?

What are you using as a heater on the J-Head? Cartridge? Resistor?

What's the resistance? (Calculate the current it's pulling)

Do you have a fan blowing on the hotend causing the heater output to be on too much?

Is there a heatsink on the MOSFET?

Do you have cooling on the RAMPS board?

So what heater is it that is causing the MOSFET's to fail? The extruder heater? Extruder heater

What are you using as a heater on the J-Head? Cartridge? Resistor? Resistor

What's the resistance? (Calculate the current it's pulling) Will not be back near the bot till Monday. Will check it then.

Do you have a fan blowing on the hot end causing the heater output to be on too much? No

Is there a heatsink on the MOSFET? Yes

Do you have cooling on the RAMPS board? No

I will be moving to a cartridge heater. Just did not have the time to hook one up.

Hello and sorry for refloating the post, but I'm having the exact same isue and I was wondering if you found a solution.
Thanks in advance.