I need some information on power dissipation of metal chassis resistors. I have 47 ohm, 50W resistors. (digikey part #A102169-ND) I hooked them up to 24V. So current flowing is about 0.51A But the resistors get too damn hot to touch(48-55 deg C, just after a few mins(~5mins). The power dissipation is 12W. But these are rated 50W, 4x more. This is not the first time I am using these. But I am surprised by how hot they get. Any guidelines or app note on these resistors and power dissipation? The ambient temp is 25 deg C. Resistor datasheet says 50W at 25 deg C, without heatsink.