Building a constant current/constant power electronic load


Kerry Wong built a DIY constant current/constant power electronic load.  It can sink more than 200W of power:

A while back I built a simple constant current electronic load using an aluminum HDD cooler case as the heatsink. While it was sufficient for a few amps’ load under low voltages, it could not handle load much higher than a few dozen watts at least not for a prolonged period of time. So this time around, I decided to build a much beefier electronic load so it could be used in more demanding situations.
One of the features a lot of commercial electronic loads has in common is the ability to sink constant power. Constant power would come in handy when measuring battery capacities (Wh) or testing power supplies for instance. To accommodate this, I decided to use an Arduino (ATmega328p) microcontroller.

Check out the video after the break.

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  1. Hello.
    Very interesting design. But I have not arduino and it would like to complete schema with MCU. And program in hex​​.

  2. Sorry to say this, but if you’re not able to find a a schematic of an Arduino clone and can’t add that into the schematics yourself this project might be a bit too advanced for your current level of electronics knowledge. This constant current load handles voltages and powers well into both (almost) lethal range as well as having the capability to make parts burn and/or explode if not handled correctly.

    You might want to look into the re:Load made by a guy here from Dangerous Prototypes.

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