Looks like it switches different ranges. ST makes something similar that has similar dynamic range without switching. They use analog circuitry (op amps and junk) to compensate for the resistor drop, so the path is uninterrupted. I've had systems where the auto-ranging on a bench meter is enough to cause it to reset. I can't find a schematic for the PPKII (haven't looked too hard though) but if it's actually switching the supply, that can cause issues to devices downstream. Especially if that switching causes a voltage drop change.