Nikon COOLPIX P520 Reference Manual page 201

C
The Charge Lamp
The following chart explains charge lamp status when the camera is connected to a computer.
Option
Flashes slowly (green)
Off
Flashes quickly (green)
Battery charging.
Battery not charging.
If the charge lamp changes from slow flashing (green) to off
while the power-on lamp is lit, charging is complete.
• The ambient temperature is not suited to charging. Charge
the battery indoors with an ambient temperature of 5°C to
35°C (41°F to 95°F).
• The USB cable is not connected correctly, or the battery is
faulty. Make sure the USB cable is connected correctly and
replace the battery if necessary.
• The computer is in sleep mode and is not supplying power.
Wake up the computer.
• The battery cannot be charged because the computer cannot
supply power to the camera, due to the computer's settings or
its specifications.
The Setup Menu
Description
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