UL Registration Number

If the power supply you are trying to discover the real manufacturer isn’t 80 Plus-certified, then the second way to try to discover its real manufacturer is through its UL registration number.

On the label of almost all power supplies there is an Underwriters Laboratories (UL) record number, usually very small under a logo that looks like an “UR” seen in the mirror (we will show this logo on the pictures below, so you will know exactly how this logo looks like). With this number, you can go to UL’s website and check who is the owner of that record.

Click on the link above and enter it on “UL File Number” and then hit “Search.” Then you should see the name of the company that applied for the UL certification.

If the system returns the name of the power supply brand and you know that it is not the real manufacturer, this means that the company paid to have its own UL number, and you will have to use other methods for discovering the real manufacturer.

For example, consider the power supply shown in Figure 1, which is sold by OCZ. Researching this UL number the system returns “OCZ Technology” as the registrant and since we know OCZ doesn’t have factories, this means that they paid to have their own UL number.

OCZ Z Series 1000 WFigure 1: UL number for OCZ Z Series 1000 W (returns OCZ as the registrant)

But if you are lucky, you will be able to discover the real manufacturer. We give a few examples below. Try entering the UL numbers provided in the pictures below on the UL website to see how this works by yourself.

Our friend JonnyGuru has a complete list of all known UL numbers, with the real manufacturers, link to their websites and which companies sell relabeled power supplies from them.

Power Supply Real ManufacturerFigure 2: Antec Neo HE 550 is manufactured by Seasonic

Power Supply Real ManufacturerFigure 3: Thermaltake Toughpower 750 W is manufactured by CWT

Power Supply Real ManufacturerFigure 4: Cooler Master RS-500-ASAA is manufactured by AcBel Polytech

Power Supply Real ManufacturerFigure 5: OCZ ModStream 520 W is manufactured by Topower

Unfortunately power supplies that aren’t targeted to be sold in the USA may not have a UL number. And a few power supplies carry the UL logo but not the UL registration number. And we have even seen a couple of very low-end generic “Made in China” power supplies with fake UL numbers (numbers copied from another power supply)!

Gabriel Torres is a Brazilian best-selling ICT expert, with 24 books published. He started his online career in 1996, when he launched Clube do Hardware, which is one of the oldest and largest websites about technology in Brazil. He created Hardware Secrets in 1999 to expand his knowledge outside his home country.