Safe In-Wall AC to DC Transformers??

[Moshe Livne]

@Didi it is cheaper to buy better fire and life insurance :wink:

[Didi]

@Moshe-Livne said:

@Didi it is cheaper to buy better fire and life insurance :wink:

That´s a good point :joy:

[scalz]

@Moshe Livne: it is ordered, I have not them yet. I hope it will be good quality.I don't know.
I agree with you for fire and co. But I think in commercial products they don't use big things.
As we can see on some picture here : http://www.aliexpress.com/store/product/Free-Shipping-Livolo-Luxury-White-Crystal-Glass-Switch-Panel-EU-Standard-VL-C701-11-110-250V/500715_512886492.html
Sure it is maybe not top quality, but I think in fibaro or other it's near the same thing. but I am not sure as I have none. And of course they have enclosure (maybe flame retardant).
Maybe I am not enough paranoid...or you can for example put an onboard temperature sensor for additional security.
But of course, ac is very dangerous, you must know what you do if you don't want to die. You have to take all securities like you said.

[petewill]

Thanks for the quick replies! I am torn. The ones @Didi posted look great but they are large and expensive. The ones @Moshe-Livne and @scalz ordered look appealing because of cost and size but I don't want to sacrifice safety for cost. It looks like they have temperature protection but I don't know enough about electronics to test for safety. Hmm...

[BulldogLowell]

@petewill

I wonder if you could open one of these and solder to the USB power leads...

[petewill]

@BulldogLowell Yeah I was thinking about that too. I'm really trying to keep costs down though. When I hit the $25 price point it's almost as much as a standard z-wave switch when all the other parts and time are included.

[RJ_Make]

My only recommendation; (if you are going to put this in side a utility box, in the wall) might want to find a solution that has the 3 standard safety features. (OTP, OVP, SCP)

These work well, but you need to follow the data-sheet for noise and ripple control.

[petewill]

@ServiceXp Thanks! I wonder if I can steal one of those from an existing device. Any idea what those would be used on?

(OTP, OVP, SCP)

Also, is that Over Temp Protection, Over Voltage Protection and Short Circuit Protection??

These say they are certified and have temp, voltage and short circuit protection. Think it can be trusted?
http://www.ebay.com/itm/351418782712?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

[sundberg84]

This post is deleted!

[Moshe Livne]

@petewill @ServiceXp here is the datasheet http://www.hlktech.net/product_detail.php?ProId=54

it seems to have SCP and OCP but the OTP part seems to be left to the elements. I don't see OVP. I understand nothing of this.... Again, these looks well made, none of the crude soldering and flimsy elements you can see in the other converters (including the ones you get from wall warts). However, it being fully enclosed hides most of the details.

[Didi]

@Moshe-Livne said:

@petewill @ServiceXp here is the datasheet http://www.hlktech.net/product_detail.php?ProId=54

I will give them a try and order some for testing in a flush box.

[Moshe Livne]

@Didi Shame you won't be able to get them for the 4th of July :-)

[petewill]

@Didi said:

I will give them a try and order some for testing in a flush box.

Great! Let us know what you find. Thanks for doing this!

[RJ_Make]

@petewill said:

@ServiceXp Thanks! I wonder if I can steal one of those from an existing device. Any idea what those would be used on?

(OTP, OVP, SCP)

Also, is that Over Temp Protection, Over Voltage Protection and Short Circuit Protection??

These say they are certified and have temp, voltage and short circuit protection. Think it can be trusted?
http://www.ebay.com/itm/351418782712?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT

Yes that is correct, and I don't think the HLK-OM01 has OTP, so for me, it's out. You looking for a 1 off transformer, or do you have some projects in mind?

[petewill]

@ServiceXp I was thinking about replacing a wall switch. So far all my projects have been outside a wall and I want to make sure I don't do anything stupid with this one. So, one off for now but I may make more in the future.

[DrJeff]

I'm seriously thinking it skipping all of these and build a transformerless circuit directly to the board like a true in wall switch, Pete do you want to share this project. I've been playing with this for a little while but haven't had time to put it all together. I can point you to all the places but a board will need to be designed for the switch, that's almost where I'm at! 😀

[sundberg84]

Just à thought... I have these cheap 1$ 240 to 5 v USB power adapters charging 5-6 different equipments every day. These was sent with the equipment as standard so why are they not be safe?

[tbowmo]

@sundberg84

Some of the aftermarket wallwarts on ebay are very flimsy builds.. Lot's of teardown videos around, describing the different problems with them (like isolation distances not being kept at correct sizes etc).

[Moshe Livne]

@tbowmo @petewill @didi @ServiceXp I think I found the perfect one!!!!
http://www.jameco.com/webapp/wcs/stores/servlet/Product_10001_10001_2155823_-1
http://www.mouser.com/ds/2/260/GS05U-USB-spec-33533.pdf

it is made by meanwell, so not flimsy. has all protections. 8$ at jameco and mouser and I am sure my meanwell supplier on aliexpress can get it for me at half price... it is a shame that they do not sell the inside separately but nothing is perfect.
the only problem might be breaking it apart. Meanwell really make sturdy enclosures.
let me know what you think...

[Moshe Livne]

@sundberg84 I am using these as well, but not enclosed in a box or in the wall. Big difference.... when enclosed, the temp builds up and all the warning signs are hidden so its too late when you see smoke coming out of the wall. If a wall-wart combust on the outside of the wall chances are nothing serious will happen. If it does that inside the wall, with wooden frame nearby its a bit of a worry.