Safe In-Wall AC to DC Transformers??

[dbemowsk]

@soloam I too had great trouble with this. The best trick that I found was to have the side of the board with the fuse on it resting on a frozen gel pack while soldering. As long as you keep the fuse cold it should not blow. It is called a thermal fuse for a reason. I have talked to others that have had some success with aluminum heat sink clips like these that you would clamp on the lead that you are soldering to pull the heat away before it reaches the fuse.

I still prefer the gel pack solution though. If you set yourself up right with the gel pack, you can have the cold pack pressing the thermal fuse against the power supply module as you solder which is where you want it anyway.

[Soloam]

@dbemowsk are you talking about this:

I'll try it out.

where can I find that clamps? To try out also?

Thank You

[dbemowsk]

@soloam Those are the type I am talking about. Put them in the freezer for a bit. They should still be pliable when they come out.
https://www.amazon.com/CLIP-HEAT-SINK-KIT/dp/B0032UYTV6

[TD22057]

You don't really have to buy anything - lots of things will work to keep the temperature down. A wet paper towel wrapped around the fuse or submerge it in a small cup of water (easy for through hole components when the board is upside down) or wrap with 2 wet sponges and some rubber bands, etc etc.

[jeremushka]

@sundberg84 I am building an efficient AC/DC power supply to avoid using the HLK-PM01. I design the power supply with flyback topology with high safety as it is fully isolated.
in the current design i selected the component BF1550. It is a high performance AC/DC power supply control
device which is operating in primary side sensing and regulation. It includes an internal power BJT and is designed for off-line power supplies within 6W output power.
Based on that, i designed the transformer. I need to find a factory to produce it.
My goal is to introduce in any nodes this AC/DC power supply for safety reason and efficiency DC regulation.

[beic]

I know it's an old topic, but I need to ask...

I read all this things mentioned on this topic, but at the end I did not find any answer to the fuses and for the varistor.

So, I wonder what values was used:

1. for fuses on mains 230v and for the 5V DC side?
2. I don't see any varistor values like 10D271K, 10D471K or 10D561K?

And also one suggestion about that thermal fuse, it would be better to use KSD-01 (normaly closed type) at 65C degree.

[Omemanti]

For anyone interested, and to correct my mistakes, I just put up an NRF52 node that is powered by an off the shelf ac/dc converter to be used as a repeater node.. feel free to comment

https://www.openhardware.io/view/613/NRF52-Wall-Node-ACDC

This topic did most of the research for me, so thank you :)

[rmh]

Received some hilink transformers today from QIMEI Electronics Network Technology Co., Ltd in China; Compared to the posts above, the 3.3v ones look genuine, but not sure about the 5v ones.

The side the pins come out of does not have the central hole and feels 'squigy' so I lifted it off one of them and the space inside is not completely filled with the encapsulation stuff, but it does feel slightly rubbery like the real ones...

Maybe a new variant of the real thing? Or fake?

These are destined for being outside in waterproof boxes, so I'll let you know if any catch fire....

Richard

(

[Yannik Mündler]

anything new @rmh ?
I just received five of them looking the same like yours.
bought from user 7856632 from ebay

[TomG]

I recently ordered 10 HLK-PM01s from WAVGAT Store on Aliexpress.com. The photo on their advertisement is the same, and looks like you expect, for a genuine Hi-Link product. The products I received recently were the same as @rmh received. The last time I ordered these in July 2018 from WAVGAT Store, I received the same product as their photo. I think I am going to open a dispute and see what happens.

[TomG]

@dbemowsk I tried a similar clip, but it didn't work (the fuse still blew when I soldered it). A small piece of wet sponge and a small clip to hold it around the wire lead work the best for me.

[TomG]

I emailed Hi-Link about the HLK-PW01 power supplies that @rmh, @yannik-mündler and myself purchased. These are the power supplies with a removable bottom.

I sent the following email to Sunny at Hi-Link (contact info: http://www.hlktech.net/contact.php).
++++
Hello,

Are the two HLK-PM01s in the attached images genuine Hi-Link parts? A major difference is the part on the right has a bottom cover that is easily removable.

I bought the part on the left from an Aliexpress seller in July 2018. The part on the right was bought from the same Aliexpress seller in May 2019.

Thank you very much for your help.
++++

Here is Sunny's reply:
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Now all of our module are use new version .

The one you bought on 2019 is the new version, the old version is not used yet.

By the way,May I know you are the final user or the reseller?

If you are worried about it,you can buy from our website www.hlktech.net or our Aliexpress store https://hlktech.aliexpress.com/store/211069 directly.
++++

I went to the Aliexpress page in their email and found the HLK-PM01 page. On that page they say:
++++
Recently,there are many fake module in the market,in order to Standardize the market environment,keep benifit for the customers,We,Hi-Link,changed our module to the new but more quality version,the back of new version is show as the following picture,currently,the old version and new version were sent random,please pay attention to that!thank you very much!
++++

They also show images of the previous version (which we are all familiar with) and the new version (with the removable bottom).

So, it appears the HLK-PW01 power supplies with the removable bottom, from a reliable vendor, or directly from Hi-Link, are genuine Hi-Link power supplies.

Below is my two images of the bottom of the two genuine power supplies (old on the left, new on the right).