Nikon D500 - Manual (Page 152)

152 Menu Guide
Choose whether the battery in the camera or the batteries in the
battery pack are used first when an optional MB-D17 multi-
power battery pack is attached. Note that if the MB-D17 is
powered by an optional AC adapter and power connector, the
AC adapter will be used regardless of the option selected.
A w icon is displayed in the camera
control panel when the batteries in the
MB-D17 are in use.
Battery Order
G button
➜ B setup menu