Kerry Wong did a teardown of an Array 3711A 300W electronic load:
I have made many electronic loads in the past. For instance this simple harddrive cooler housed small dummy load, this more sophisticated constant current/constant programmable load and this heavy-duty electronic load that is capable of sinking over 1kW under peak load. In this blog post though, I am going to take a look inside an Array 3711A DC electronic load I recently purchased on eBay. You can find a video of this teardown towards the end of the post.
See the full post on his blog here.
Check out the video after the break.