Dell Latitude 810 Laptop and its 19.5V AC-powered charger: The charger plug seems to have three coaxial connections, the outer sleeve, the inner sleeve, and a center pin (see pix).
When plugged-in, 19.5Vdc appears between the outer sleeve and the inner sleeve, with no definite voltage on the center pin, measured with respect to either outer or inner sleeve.
Is the center pin some sort of feedback input to the charger? Is it even connected?
When plugged-in, 19.5Vdc appears between the outer sleeve and the inner sleeve, with no definite voltage on the center pin, measured with respect to either outer or inner sleeve.
Is the center pin some sort of feedback input to the charger? Is it even connected?