Author Topic: Mini power supply - legit or death trap?  (Read 2211 times)

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Offline Lucky-LukaTopic starter

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Mini power supply - legit or death trap?
« on: May 07, 2022, 08:09:51 am »
Hi all
I was looking for a power supply for my Arduino based PCB.
I have found this item:
https://www.az-delivery.de/it/products/copy-of-220v-zu-5v-mini-netzteil
There is its datasheet in that page and its marked as CE...
Any thoughts?
Memento audere semper.
 

Offline bd139

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Re: Mini power supply - legit or death trap?
« Reply #1 on: May 07, 2022, 10:12:26 am »
Probably fine.

The PCB design you use for it, if certain standards are not met such as creepage, termination etc, is likely to be more dangerous than the power supply module.
 
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Offline kripton2035

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Re: Mini power supply - legit or death trap?
« Reply #2 on: May 07, 2022, 10:23:26 am »
same modules here

https://www.aliexpress.com/store/group/Module-d-alimentation-ca-cc/4296027_513414642.html

half the price. you only have to wait 15-30 days for delivery.
I already bought some from this seller. they works fine.
 
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Offline elekorsi

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Re: Mini power supply - legit or death trap?
« Reply #3 on: May 07, 2022, 10:53:06 am »
You have them also from Meanwell, it is the IRM series
Here you have one that has the same power as the one on your link. https://www.tme.eu/si/en/details/irm-03-5/built-in-power-supplies/mean-well/
IRM-03-05 means 3W, 5V
You can choose between different power ratings, check their website...
 

Offline kripton2035

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Offline Lucky-LukaTopic starter

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Re: Mini power supply - legit or death trap?
« Reply #5 on: May 07, 2022, 03:40:21 pm »
What is TME? Is is legit?
Memento audere semper.
 

Offline elekorsi

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Re: Mini power supply - legit or death trap?
« Reply #6 on: May 08, 2022, 06:24:23 am »
One of the main suppliers in europe... i order from them 1-2 times per week. If i order before 13.00, it is delivered next day   :-+
 

Offline Ice-Tea

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Re: Mini power supply - legit or death trap?
« Reply #7 on: May 08, 2022, 07:06:11 am »
A brick like this just about burned down a mates house. I have been warning him about Alibaba special orders and he's always shrugged it off.

It was part of a fan controller he used for his server cabinet. A spike on the grid took out the module and burned the controller to a crisp. For good measure, it destroyed his UPS (which should not have been possible, but hey...).

The Alibaba special did not have any overvoltage protection on the PCB even though the datasheet for the module clearly listed it as a requirement.

Bottom line:
- get a reputable brand (such as the mentioned Meanwell)
- get one with a datasheet clearly indicating which external components are required (and follow the instructions rigorously)
 
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Offline janoc

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Re: Mini power supply - legit or death trap?
« Reply #8 on: May 08, 2022, 08:04:57 am »
What is TME? Is is legit?

https://www.tme.eu/

Originally Polish company but they have offices all over Europe now. Completely legit.
 
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Offline Ian.M

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Re: Mini power supply - legit or death trap?
« Reply #9 on: May 08, 2022, 10:30:39 am »
AZ-Delivery are a German company that seem to have at least *some* idea what they are doing with respect to safety.  e.g. their relay modules are only rated for max. 50V AC, not the 220V-250V that is claimed by most cheap Chinese relay modules, and they are unlikely to want to risk selling CE marked stuff under their own brand name that they don't have the compliance paperwork for.   


However I'm not sure whether I would trust their PSU modules if the output cant be grounded in your application, as even if the design is sound, there are so many ways for a Chinese contract assembler to screw you over and its very hard to inspect a potted module after assembly.   If it passes a HIPOT test and the output can be and *is* grounded to mains PE,  I personally would be reasonably happy with it.
 

Offline wizard69

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Re: Mini power supply - legit or death trap?
« Reply #10 on: May 09, 2022, 11:15:13 am »
Well first it depends upon your board and how you implement it.   Once you have line voltage on an Arduino you need to have the proper safety implementation.   That includes properly isolated line voltages and a cabinet or chassis that keeps you out of contact.

As for the power supply itself, I have no idea with respect to that brand.   Board mounted bricks like this are pretty common these days but you need to source from a reliable manufacture.   Cheaping out on a power supply is generally a bad idea with a microcontroller or something larger like a PC.

Another point; I generally prefer that a power supply be off board.   Power supplies are often the failure point and if you are left with replacing and entire PCB due to a power supply failure you will end up with a frustrated customer.   This especially in the embedded world where a board might run 20 years.   Obviously there are different requirements but if you put a power supply on board it ought to be a reliable one.

Hi all
I was looking for a power supply for my Arduino based PCB.
I have found this item:
https://www.az-delivery.de/it/products/copy-of-220v-zu-5v-mini-netzteil
There is its datasheet in that page and its marked as CE...
Any thoughts?
 

Offline TimNJ

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Re: Mini power supply - legit or death trap?
« Reply #11 on: May 09, 2022, 01:27:28 pm »
For any AC-DC power supply, intended for connection to mains, I’d like to see a UL or ETL mark printed on the housing or label. This indicates at least one 3rd party safety approval on the unit. It’s not an absolute guarantee of good quality, but it is a start. CE and double insulated mark mean pretty much amount to nothing.
 
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Offline mikerj

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Re: Mini power supply - legit or death trap?
« Reply #12 on: May 09, 2022, 06:17:12 pm »
Never mind the quality of the PSU module, I'm more concerned that they advertise it as "breadboard compatible".  Encouraging some noob to hook up 240v to their breadboard seems less than ideal.
 

Offline metrologist

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Re: Mini power supply - legit or death trap?
« Reply #13 on: May 09, 2022, 07:59:40 pm »
like a dream come true

 
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Offline Ian.M

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Re: Mini power supply - legit or death trap?
« Reply #14 on: May 09, 2022, 08:48:02 pm »
AARGH!  ZZZZZZAAAAAAPPPP!!!

Right, that "breadboard compatible" drops my confidence in AZDelivery PSU modules to  a pretty low level, though still slightly above the Chinese resellers cr@p.

I should however confess to having built mains powered circuits with similar PSU modules on stripboard, though I did strip tracks with the aid of an Xacto knife and a soldering gun to achieve more than adequate creepage and clearance distances.
« Last Edit: May 09, 2022, 08:50:52 pm by Ian.M »
 

Offline bd139

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Re: Mini power supply - legit or death trap?
« Reply #15 on: May 09, 2022, 09:34:51 pm »
like a dream come true



That's hilarious. Nearly spat my hot chocolate all over my laptop  :-DD
 

Offline tepalia02

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Re: Mini power supply - legit or death trap?
« Reply #16 on: May 14, 2022, 10:59:05 am »
I do not think there will be any problem if you do not touch the component with a bare hand. To be in the safe side, I prefer using some kind of enclosure.
 

Offline AndyBeez

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Re: Mini power supply - legit or death trap?
« Reply #17 on: May 16, 2022, 02:44:06 pm »
 ??? Seriously?

This looks like the kind of AliExpress module that YouTube's Big Clive does a video on: "Seriously lethal micro power supply module thing... with schematic"

I would feel safer reusing the un-switched mode power supply from a dead 240V LED light bulb and sticking the PCB inside a plastic TicTac box. After writing 'CE' on the outside, plus 'TUV' and 'UKCA' for good measure, I will fill the box with sand to absorb the arc/magic smoke for when the protection diode dies.

Let's keep power bricks off Arduinos! And Raspberry Pi's.
 
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Online ebastler

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Re: Mini power supply - legit or death trap?
« Reply #18 on: May 17, 2022, 06:50:43 pm »
bd139 said it in the very first reply, but I'll word it differently:

It does not really matter whether the power supply module is well-designed inside. For a rank amateur (like the OP, based on this and other questions he asked), there are just too many things one can get wrong when designing the PCB and enclosure around this module.

@lucky-luca -- please use a wall wart or other well-designed, fully encapsulated supply which only outputs extra-low voltage.
 
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Offline ConKbot

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Re: Mini power supply - legit or death trap?
« Reply #19 on: May 18, 2022, 04:13:06 pm »
+1, a module like that, regardless of supplier isn't a finished product. The rest of a power supply needs to go with it. Fusing, surge protection ,(see post above by Ice Tea), probably some EMI filtering, and an enclosure to keep people's grubby mitts away from mains.
 

Offline Infraviolet

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Re: Mini power supply - legit or death trap?
« Reply #20 on: May 20, 2022, 09:42:16 am »
For a quick 5V supply I'd tend to suggest getting a good quality mini/micro/C USB phone "charger" and buying an adapter board which breaks out USB to 2.54mm pins. Raspberry Pi branded power supplies are a good option, if a bit pricier, up to 2A and a fairly stable regulated  5V voltage, and no "smart" stuff which tries to cut off power if you draw too small a current and ignore the data lines entirely (some other USB chargers may need those pulled high or low to supply power).
 

Offline langwadt

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Re: Mini power supply - legit or death trap?
« Reply #21 on: May 20, 2022, 10:27:19 am »
For a quick 5V supply I'd tend to suggest getting a good quality mini/micro/C USB phone "charger" and buying an adapter board which breaks out USB to 2.54mm pins. Raspberry Pi branded power supplies are a good option, if a bit pricier, up to 2A and a fairly stable regulated  5V voltage, and no "smart" stuff which tries to cut off power if you draw too small a current and ignore the data lines entirely (some other USB chargers may need those pulled high or low to supply power).

USB standard "dedicated charger" identifies itself by having the datalines shorted together
 


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