Recalling my recent post about USB sticks not delivering the stated storage sizes, this tester looks pretty interesting for testing USB fast chargers. There are supposedly similar issues around USB fast chargers that chronically overheat and are not up to spec.
Most USB charger testers are just voltage and current measurers, but this device goes way beyond that. Not only does it test for the various USB-C charging modes, ripple and noise testing, eMarker detection, and lots more.
The device claims the ability to monitor 4-28V, 0-7A, 0-120W and can integrate capacity/consumption. Resolution is claimed to be 10uV/uA/uW. It supports USB-A, micro-B and type-C connections.
It also has PC and Android apps to obtain more advanced views.
I see many people complaining they don’t get full speed charges, or a device is not starting properly, and it is mostly due to the USB-C power output not being sufficient. With a device like this it is a lot easier to diagnose whether it is the charger or the cable at fault (an incorrect USB-C cable will negate advanced USB-C charging or power delivery).
See https://goughlui.com/2023/04/29/review-tested-fnirsi-fnb58-usb-fast-charge-tester/