Well, I must say, I am very happy with the result. Thanks for the testing.
So, I am already planning to use it in a number of devices. To avoid too high temperatures in confined boxes, it might be a good idea to glue a temperature fuse to it and wire it in series with the live mains wire. When the temperature rises above, lets say 75 degrees celsius, the fuse breaks down.

Looks very nice, but you cannot use it for sensors or actuators that can be touched by hand and do not comply with the insulation standards, since parts of it will be connected to mains.

Is there any news from the test guy?

@petewill I think this is a wise decision.
I liked the discussion on this thread, so I have to thank you too.

Now it is waiting time. Waiting until the hlk-s arrive at the lab of the test guy.
My Chinese friend said, the package is on its way.

@rvendrame said:

@Atomfire said:

Not a big fan of soldering SMD components and I cannot find standard components, how essential is the 2nd fuse and varistor on the 5v side?

We are trying to make it as safer as possible... Assuming such modules will stay in a wall box, very close to wires and/or other potential fireable materials, we should try to mitigate risks as much as possible.

As I mentioned above --- This is DIY, also means 'risk it yourself'. Don't tell your insurance company ;-)

That is why I prefer to use fuses that blow, like the ones I mentioned earlier.
The resettable fuses also get warm. Can't wait for the package from Conrad to arrive. I am dying to do some further testing.

With respect to the brave HLK ... it is on for some three days and it is stable.

Short update ... yesterday I asked or Chinese friends from Alie to send a HLK module to our test friend.
I also did an insulation test with 1000 Volt. The test shows more than 1000 MOhm between ac and dc. So far so good.

@aproxx This is a different kind of notation, but when I look the device up in de Bourns catalog, I see it is rated for 250 Vac. That should be good.

link text

@aproxx The only varistor I see in your list is 5.5 Volt.

@aproxx I would say that the 50 mA fuse is too weak. The HLK draws between 0.1 and 0.2 Amp and can surge 10 Amp. So, I think the 1A version is good for both situations input and output. The varistor is only good for the output.
One thing to consider though. This is also chinese stuff ... is it really safe or are we introducing a new problem? :smile:

@rvendrame said:

@Moshe-Livne said:

@rvendrame Considering cost of postage and logistics involved it would probably be cheapest to just order two units from Ali to him? its 8$ including shipping if i remember correctly

Yes, it makes all sense. The only downside is that if we buy all at same time probably he will get all from the same lot, but in my opinion it by far doesn't invalidate the testing.

So, myself, @Bertb , @Didi = 3 PSUs, better than 2. I will share with you both the ship-to address ok? Thanks a lot!

:+1:

I managed to borrow a Megger (high voltage resistance measurement device). This weekend I will test the insulation of the MLK.
The only drawback is that the Megger reaches to 1000 Volt.

As you please ...

voeding.pdf

... it must be friday ...

voeding.doc

@rvendrame said:

Hey guys, I wrote to the owner of the site suggested by @Moshe-Livne. He replied saying that he can test the HLK.

He mentioned that usually he takes at least two units (so if one burn he can continue the testing). I will send one from my lot, perhaps we have a brave guy to gave up one more? (a sacrifice of few to save many ) ;-) Let me know and I will share the address via PM (Denmark).

I am in for this.

Something went wrong with uploading the file, I think.
Herewith a new schematic with a suggested bill of material.
It is highly experimental still, but I ordered the components yesterday.

I am specially interested in working with the PTC fuse.

I hope the proposed circuit works for you. Please keep the maximim continuous output power in mind. It is only 3 Watts (600 mA).
In some cases you might need to add C1's (rule of thump 1 per chip or chip VCC) and/or need to increase the value of C2. This depends on the fluctuations in the power demand.

With the proposed values for C1 and C2, the ripple remained below 50 mV at 500 mA.
Also keep in mind that a remaining oscillation frequency residue appears in the output of some 60kHz.. If capacitors are not able to filter that out, a small coil might be needed.

Well it is experimenting that makes this fun, isn't it?

@petewill The schematic is just a simple draft. It can be seen with IE.

@Atomfire I will come back to that tomorrow.

@ThinkPad Well its your desk, so its fine with me.
Is there a way to get your address without shouting it from the rooftops?

@ThinkPad I am not sure it is still safe to operate.

Just to be sure everybody understands the schematic, hereunder a schematic.
I am not a fan of blowing mains fuses ...

Draft schematic