PROTOTYPE: Heated bed mosfet relay V3

youmagine

Important note: There's a critical flaw in the design! It doesn't function as described here! Please hold tight until I find the time to fix it. Thanks. NOTE: This is an untested prototype layout. I've got limited time available and won't be able to build and test one myself in the next few weeks. However, I wanted to release this because I know some folks have been waiting for it for a long time now. Disclaimer: UNTESTED DESIGN! Please experiment responsibly and be prepared to face problems with this. I believe it will work just fine. It's a simple layout and I'm confident there are no errors. If you don't think you're the right person to test this out, then please wait for someone to confirm that it's working smoothly. Some crucial documentation is still missing, but you should be able to build and use this using the information from the old design. About the improvements: Version 3 uses an optocoupler to isolate the input voltage from the output voltages. This makes it universally compatible with any 3D printer electronics platform and lets you use one power supply unit for everything, or separate units. Performance is identical to V2 - this thing shouldn't get hot during operation, at least not in "bang bang mode". PWM mode isn't recommended for the heatbed. You could try, but keep track of the mosfet's temperature.