problem whit sanguinololu card

[cadfinger]

thank you for your help. Is the resistance value what you will need to determine what mosfet I will need to replace the damaged component or is this a standard component on the sanguinololu 1.3a? if this is a standard kind of component im pretty sure i can find it locally if i know what to ask for at the electronics shop. my meter is at work so i will have to post the resistance of the bed tomorrow.

[zhangxueyou]

Generally, it is hot bed with lower resistance that caused the MOSFET burnt, so I want to check if the hot bed is qualified. It should be 1.2 ohm or more.

[cadfinger]

I checked the resistance and am getting 1.0 - 1.1 at the contacts on the heated bed. is that close enough to work. I ordered the mosfet to replace on the board but I would hate to replace it and burn it board again. Any suggestions, maybe adding a resister to the circuit or replacing the bed?

[zhangxueyou]

If the cooling is working and the MOSFET is near to fan, it can not be burnt.
Adding a resistor is not reliable.

[johnz]

Did you find out what the problem was?? I'm having the same problem!! Mine burnt out at the same place as yours!!