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I'm given a AC to DC power supply with only the inputs and output specified. It was probably made after 2000, and the ENERGY STAR program mandate to add PFC correction to power supplies may or may not have been implemented.

Some of these are AC power bricks (e.g. laptops), others are PC case supplies.

We've a bench to set the supply on which has multimeters, an oscilloscope, plus parts (resistors, caps, chokes) to rig up some loads for the supply.

What can I do on the bench to determine if the supply probably does/does not add back a PFC?

I need to avoid hooking a newer PFC supply to an older/cheaper non-sine wave UPS (Uninterruptible Power Supply). A stepped wave form from a UPS on battery can blow the PFC supplies.

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    \$\begingroup\$ XY problem! What makes you think a PFC would be destroyed by a non sinusoidal input? I’ve tested all of mine with full square, trapezoid and saw wave during type testing to smoke out any design flaw. \$\endgroup\$
    – winny
    Commented Aug 22, 2019 at 14:44

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Hook up a current probe on the AC line, and look at the AC voltage and current simultaneously. If they're the same shape, then the supply has PFC (or, at least, doesn't inject harmonics of the voltage into the current).

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  • \$\begingroup\$ Duh! {slaps forehead} Thanks! Will try it out tomorrow if the Friday rush doesn't overflow. \$\endgroup\$
    – HiTechHiTouch
    Commented Aug 23, 2019 at 1:41

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