Unable to get Heatbed to 100 C temp . Using computer SMPS 450 W . Even insulated heatbed from back side . What might be reason ?? Anyone can help?
Measure the current draw to start, assuming you have 2 or 3 voltmeters capable of 10A each you would tie the VMM leads together in parallel then stick that in series of the power to the bed.
That way you don’t blow out the VMM.
Then add up the readings of each meter for a total amperage draw.