Right choice of USB Power Supply for product

[Twistx77]

Hi everyone,

I want to sell some furniture that has some electronics on it and I have some doubts about the power supply and regulation. 

At the moment I have a different prototypes working and I need to decide on a USB PD wall brick supply to go through EMC Testing. I guess I will need to test my electronics with a certain USB PD power brick and a certain cable so I can sell the furniture with those included.

For that, I need to find a manufacturer of this USB PD wall bricks since I don't want to design my own. The thing is that I can't seem to find a EU or US manufacturer that would sell them to use in my product. All I could find are Chinese websites and Alibaba. I have had good experiences with Alibaba so far but I am worried about the actual legality of their "CE / FCC / UL, etc" certifications and the fact that maybe next month the seller wont be there anymore and I would need to change my supply.

Does anybody not respectable companies selling these? If I go for Alibaba and  pick one charger with the CE / FCC / UL certification, do I have to actually include the supply for the EMC test with my device or can I just include any "certified" supply with my product? This last thing would actually allow me to use any other supply that meets my requirements without doing any revision on the certification of my product.

Any information about these topics are greatly appreciated. It is hard to find clear information about this topics on the web.

Thank you

[mon2]

Hi. Been attending the numerous electronic fairs in Asia for the past ~20 years in HK. They are a must visit and should be on your list of things to do, after this covid nightmare slows down. Pending a clean slate, hope to visit the fair this October but the dates are not yet announced so it may be virtual again.

In the past, have absolutely seen firms with pre-built modules for use in furniture. Looked like a massive Staples office store with clean tables with assorted mounted power widgets.

You can start with this vendor:

https://xjynew-epoch.manufacturer.globalsources.com/homepage_6008851511454.htm

Do review their # of years in the business. If they sell toys along with these goods, I would give them a pass. Have seen some that will just be 'traders' and flip anything for a dollar. It is the way of the east. If it is popular, sell it today and next week it will be something else.

You only want to deal with the manufacturers.

You can, at your expense (which is not much and ~200 USD / day) - perform an onsite audit from ISO certified inspectors. They will act as your agent and inspect the company; visit them; supply you with an audit report for your review. Global Sources along with others offer such services.

Many / most of these companies are real. They want your business while others are looking for the next 'Apple'. This week, we were frowned upon on our forecast of 10k-50k pc buy of AMOLED displays - seriously Been in the business for ~40 years and the vendor is being selective on who to sell to when just about everyone has these displays ? Found 3 backup vendors (real mfrs) we can use for our pending designs.

It is a large field of suppliers for just about anything you can dream of. Start with the above and consider Global Sources and/or Alibaba to broadcast out a RFQ. Your emailbox will be flooded but then you can weed through to find a proper business partner.

DO NOT prepay for large volumes of anything. Paying for samples and shipping is normal practice. Do consider to buy with escrow services if there is that option. Alibaba has a link to the vendor reviews and $$ of sales to date, they cannot fudge those values.

Be sure that the modules you select are able to meet your requirements and they can back up their claims.

Good luck.

[Twistx77]

Hi Mon,

Very useful information! Thank you very very much. I will put those in practice. Still I have the certification part of the supply which is not clear to me and if one of the things that is more out of my knowledge.

Regards,

Alex

[mon2]

Each portal - Global Source and/or Alibaba offer inspection services. Not to knock the idea, but some vendors also work with other factories and they can source a pre-certified widget on your behalf. If you want private markings on the product, then likely a tooling fee + larger MOQ will apply vs. off-the-shelf designs that are neutral in packaging / nameplates, etc.

Check the credentials of the certifications and you can cross check them against the body they claim to be compliant with. For example, if UL approved, you should be able to locate these details on the UL database and their website. For us, as an example, had volumes of MFI compliant USB cables - we paid for the approval process but before starting, confirmed that Apple indeed recognized the firm to be a MFI partner. In the end, our company name, with our new batch of USB cables are listed on the Apple website. All legit as all parts were blessed by Apple in the process and they also have samples of our final products.

I am assuming that the USB products you are after are generic in nature so many vendors should offer these. The vendors in Asia are not shy to drop names of who they supply - I recall many threw out 'Walmart, Home Depot, ACE Hardware, etc." at the trade fairs. I bumped into the buyers from Mouser (they had branded T-shirts on so hard to miss) in HK. If you really are happy with a vendor, consider to hire one of the many audit companies so you can receive a full view of pending business partner. They will take pics; inspect their facility and let you know if the small details that you may miss.

Want to repeat a small story - during one of my visits to HK, a good vendor overseas stated that we should exchange business cards and have each other's contact details on our business card for future dealings. That is, we will then have a 'HK office' and vice-versa for us in Canada. In addition, if any customer wants to visit the HK / Shenzhen factory - the entire staff will greet myself as the CEO for the day. He stated this is very common practice. Lots of smoke & mirrors in the act. With enough dialogue and research, you will know the real manufacturer as compared to a trading company who may not be around tomorrow.

Want to throw out a name for USB power devices and that is LVSUN. They are a solid company and we have bought products from them. They are always at the fairs and have put out product under other private labels. They have true approvals which they can back up with documents. You can always send off samples of any of these goods to TEST labs that will do just that, inspect the quality & perform EMI / electrical tests on your behalf. We have done this for the military, Dell, HP, Foxconn, etc. for their demands.

[Twistx77]

Hi Mon,

This information is gold for me. Thank you very much. I think with this I have a better idea on how to proceed at least for now.

Seems incredible that they can fake you being the CEO of you fake HK office for a day... But if I think about it, does not surprise me that much.

I will check LVSUN and if they have what I need I will go for them if the price is good enough.

If you ever come to Switzerland, drop me a PM I can show you around Zurich and invite you a beer or a coffee.

Have a great day

Alex

[dawnclaude]

I have seen plenty of adapters from Chicony for laptops, monitors etc. Seems like a reliable Chinese supplier ( My MSI laptop power adapter is still going strong after 6 years of abuse  )
Not sure about minimum ordering quantities. Perhaps you can buy right off the shelf?

[Kean]

Having been down this path before, do not source power supplies off Alibaba or AliExpress unless you are a masochist.  It will potentially cause grief when doing EMC testing, may require expensive certification for sale, and even more pain for ongoing supply of a consistent product.  I find it amazing that a potential supplier can send you a sample for testing which not only doesn't meet specifications, but when opened for inspection the build quality is horrendous - and yet I've seen it several times when companies I've worked with have sourced the PSU.

Stick to a known brand that has been around for a while, can supply clear documentation of safety and EMC certifications for your sales region, and is carried via various distributors.  I am a fan of the Phihong wall warts and power bricks, and can recommend them as a good compromise between price and quality.  You can get samples from Mouser and Digikey, and buy via other channels as your volumes increase.  Another brand to look at is CUI.  I've seen LVSUN on Amazon and other sites, but not sure of their quality.  They are listed on the line card of TME in Europe which is promising.