Will this circuit work for a 3A load?

Hi, I found this over-voltage protection circuit on the web and I was wondering if this would be able to drive a 3A load? I'm building a LM1085 based regulator which inherently has some current limiting protection and I was hoping to use this for over-voltage protection. Any help would be appreciated. Thanks.

No, it will not work for 3A load.

The circuit shown operates the MOSFET in the linear region; it is a series pass regulator. One potential issue with this circuit is that the load can not be GND referenced. Also note that the 1N4007 diode (which serves no useful purpose and can be eliminated), is rated for only 1 amp.

_The LM1085 will supply 3 amps_ and being that it is a voltage regulator, why add over-voltage protection? If you are protecting against the LM1085 failing, an SCR shunt over-voltage circuit is the most common way to provide protection. It shorts the output to GND and a fuse opens.