Measure USB Current without Tears - USB Power Meter

 Measure USB Current without Tears

To measure the current running through USB wires of devices we have to cut off the wire from the middle then connect DC ammeter or Digital Multimeter. This is not only tedious to do but ruins the device sometimes. 

Fortunately, there is a handy device called with several names on web "USB Monitor", "USB Doctor", "USB Power Meter", is available in the market. Anyway, I am gonna call it a USB Power Meter as it measures the power-related parameters of the USB. See Image1.

                                            Image1: USB Power Meter connected to power bank

 It measures voltage, current, time elapsed and power delivered as well. The most beautiful thing is that using this is a layman's job. Just insert it into the USB power supplier plug like charge adapter or PC port and insert USB device or cable into its port of the meter.

                                Image2: Parameters Measured

All the parameters are displayed on its screen. Voltage, Current, Time, and Power Supplied. See image2.

As we know +5V is the standard supply voltage for all USB devices, actual measured voltage is displayed on its screen

The other parameter we are most interested in which is current is displayed in milli-ampere, ma is displayed in real-time on its screen. This makes the USB Power Meter useful stuff for an electronics engineer or enthusiast. But you have to satisfy yourself at the 2A maximum current limit of the USB Power Meter.

There is another good parameter that measures power supplied in millliampHour, mAh, over time. This can be used to record how much power has been supplied to a device, while charging a phone battery with a charger we can measure how much power the battery stores and compare with labeled mAh, and judge battery aging and quality. As this parameter is recorded into the meter memory you need to Reset it before you another round of measurement. See image3 for connections

Uptime is also displayed in HH: MM format.  

                

                            Image3: Device Connections and Measuring Parameters

I am not posting any buying link as it is easily available from famous e-commerce sites. You can google it if you need one.

Do you like this device? Post your comments, views and any doubts, queries below in the comment box.

Thanks

Rajeev Mehndiratta

👾