according to the microsoft website:
The power supply has several built-in safeguards to help prevent damage to either the console or to the power supply itself. The power supply can turn itself off when there is too much current, too much voltage, or too high a temperature. Under these conditions, the light on the power supply will turn from green to orange or to red. Or, the light will turn off. When the power supply light is green, the power supply is working correctly.
To help the power supply work correctly, always try to use the following best practices:
Make sure that all ventilation openings in the power supply are free to ventilate.
Do not put the power supply on a bed, on a sofa, or on any other soft surface that may block ventilation openings.
Do not put the power supply in a confined space, such as a bookcase, a rack, or a stereo cabinet, unless the space is well ventilated.
Do not put the power supply on a stereo speaker, an amplifier, or a heat source such as a radiator or a heat register.
Plug the power supply directly into a wall outlet. In other words, do not use extension cords or power strips.
Basically, feel if it is overheated. if it is let it cool down. If not try a different wall socket. If that doesn't work you probably have a problem with your power brick or console. Try borrowing someone else's power cords.