PortaPow USB Power Monitor Version 2 (Multimeter/DC Ammeter for Solar Panels, Mains Chargers, etc)
All new improved version 2 released October 2014
This multi-meter plugs directly into any USB socket and allows you to connect any USB cable into it for charging and data transfer. It displays on screen the voltage, current and wattage which is being output, acting as both a volt and amp meter. All three are shown simultaneously, there is no need for the display to change between what is shown on screen. It is powered inline so no battery is needed, and uses low resistance components with <2mA (10mW) power consumption for the most accurate readout.
Unlike other designs, this uses an LCD display which uses less power and can be easily seen even in bright conditions, making it suitable for use outdoors to test solar chargers. If you ever need to use it in the dark, push the button to activate the backlight.
A built in flexible extension cable means you can turn the screen to face you - it won't be fixed facing the floor/wall regardless of how the USB socket is oriented and it won't block other USB sockets nearby. When its not being used the cable snaps back into the main body for tidy storage.
The meter is useful to test different USB chargers and cables to see which charges faster, how much power your device consumes during use/charging, and for solar panels with USB outputs, since it will then allow you to position the panel to maximize the energy it outputs, see what factors affect the panel's performance, and also to see when the output is too low to be worth using the solar panel.
The monitor is suitable for 0-2.5 Amps, and 3-7 Volts and has an accuracy better than 1%. For a wider range of measurements and improved precision consider our Premium Power Monitor instead - search for B00LZ07BG0.