@JohanH - thanks for your reply! I also hope and think people who build commercial products have knowledge of this :) But as a hobbyist, there are two ways to go - either you dont have to care or go bare minimum, if something happens its your own fault, or you can try to make is as safe as possible. My idea was never to make this thread a information source for a commercial product. I wanted to try to make my own products as safe as possible since I have children around. With that in mind, i want to be on the safe side of things so some things i use from here might be exaggerated. But my PCB (HLK-PM01 breakout) is working great, and I feel safe. I have had it outdoors (under roof covered in IP5* box, -20 to +30 aprox) and its been working for me for a couple of years now. Better than I had before, when i just stripped an old fake samsung charger. /Andreas

The updates have been applied to Rev 2, below we have a list of everything that has been added/modified; Modification footprint for 3 items to make it easier to mount (Slow blow fuse, Thermal Fuse and Voltage Regulator) when hand soldering. Modification to nRF24L01+ Module to remove the short to ground on VCC line. Added the additional silkscreen labeling that was missed off by accident. This should be all that is needed for Rev 2 to be a successor to the Rev 1. We still have the issue with having to use pogo pins to program through the ISP connection, or to temporarily solder jumper wire into the 6 pin connection while uploading, then everything else can be programmed through the on-board FTDI connection. Will get the gerber files generated ASAP and then get them sent off for testing production runs.