In order to find out if his Fluke 12E+ multimeter ... checking if the hidden features had received their EOL calibration by hooking the meter up to a waveform generator. Apparently, it reads ...

“With demand for calibration growing every year, Fluke 5560A [right] defines a new class of multi ... which can calibrate 4.5 digit DMMs All can deliver 30 A continuously for calibrating clamp meters ...

In the process of tearing down a Fluke 77 meter for another reason entirely ... Annoyingly, there doesn’t appear to be any way to just calibrate the AC measurements, for example.