HLK-PM01 power supply

The topic has come a few times and my general opinion is to stay away from mains, but now I need a small power supply that can go into the wall. I could gut a USB power supply, but those are not necessarily great regarding safety and opened and with wire hacked to it, it’ll probably not get better.

Attached is my design for a HLK-PM01-based supply. F1 is a 73°C thermal fuse glued to the HLK, F2 is a slow blowing fuse, VR1 is a 250Vrms MOV (I am on 240V).

I would appreciate some comments. It is supposed to go piggy back on various other PCBs, with a male pin header bridge at P2 soldered to both PCBs (so about 2mm air between the PCBs, not with a male-female pin header connection).
Any good idea for spacers for the AC side of the board? I would like to avoid making the board larger just for screw holes.

This is my first time using milled cutout for separating mains from 5V and phase from neutral. Did I do that right for services like itead or seeed?

Added an inductor and some so.e caps on the output side for denoising. I wonder if I should add a zener diode (10v or something) across the output. If a faulty HLK would send mains across to the low voltage side, this should blow the fuse.

@Elcaron, I think this is a great idea. Simply make the hlk-pm01 safer. This is discussed on the mysensors forum in great length. however I have not seen anyone produce a PCB. I would love this in a PCB and with the header you mentioned. Has this project evolved? Do you have a the PCB on dirtypcb?


I know the mysensors topic, linked it a few times whenever someone wants to kill himself with that thing.

I can absolutely send you the KiCAD files. Uncorrected issues I noticed: - Holes too close for both of my fuses, so I had to bend the leads together und them. - Holes for connector to mains too small, had to file the pins a little thinner.

Production worked fine though at Seeed, including v-cuts.

Hi, Why do you want to put an Unapproved mains power supply in a non-ventilated wall cavity?

Does you insurance company know you are doing this?

Tom... :)

Since my house is not made of cardboard, a big concrete cavity with a well made selfconstructed power supply including overheat protection, far away from anything flameable is most probably far safer than any ChinaExport catastrophe most other people have next to their wooden furniture.