Heatbed unable to heat upto 60 Deg cel.

I am using 12v SMPS power supply and MOSFET for heating my heatbed.

1) without using MOSFET , my heatbed was not able to heat up
2) now I am using MOSFET, and now after 5-10 min my heatbed heats upto 25-28 Degree Celsius. After that it beeps and gives heating error.

What could be the reason for this? What shall I do now?

1) check your power supply voltage is really putting out 12v
2) check 12v is actually getting to the heated bed (measure on bed terminals)
3) is your bed actually a 12v heated bed? some are 24v. Some are configurable. Disconnect the heated bed and measure its Resistance. A average 200x200 pcb heated bed is 130 watts. At 12v it should have a resistance of about 1.1 ohms. at 24 volt it is 4.4 ohms
4) check your thermistor plugs are not swapped. so your heating the bed but reading the hotend heating up due to the bed heating up.

Edited 1 time(s). Last edit at 06/23/2021 02:53AM by Dust.