Measuring Battery Power Manually

I have a project where a DHT11 and a SIM900 are connected to a Nano via the USB port. The USB cable is actually connected to a LiPo battery pack at 4.99V before plugging in the mcu project.

I want to know the V of the battery as it drains. Id like to measure it manually with my voltmeter.

So Im wondering if I could measure it on the usb connector of the mcu like at these green points:

usbnano.jpg

I don't think those are connected to the pins. I think those are just mounting pads.

I have a project where a DHT11 and a SIM900 are connected to a Nano via the USB port. The USB cable is actually connected to a LiPo battery pack at 4.99V before plugging in the mcu project.

Post a schematic showing your battery connections

Marciokoko:
I have a project where a DHT11 and a SIM900 are connected to a Nano via the USB port. The USB cable is actually connected to a LiPo battery pack at 4.99V before plugging in the mcu project.

I want to know the V of the battery as it drains. Id like to measure it manually with my voltmeter.

So Im wondering if I could measure it on the usb connector of the mcu like at these green points

A "LiPo battery pack" will always output ~5volt, because it has an internal boost converter.
No way to know the actual battery voltage, unless you open it.

The metal part of the USB socket is soldered to the board at those four green dots.
All connected to ground.
Leo..

This tabs (and indeed the entire shield) are normally connected to GND, they don't have to be for the USB to work but that's best practice. So measure away and if you get silly readings then the designer of that PCB didn't connect them.

That said you must have other GND connections to use as well.

@Wawa,
I think you are thinking of an ESC.
Lipo batteries don't have converters ( last time I checked)

Not sure, but I think OP means a 5volt USB battery pack like this one.
https://www.sparkfun.com/products/retired/11358

A picture/link should ofcourse have been included, to stop confusion.
Leo…

Unless someone has invented a new chemistry since I last looked a LiPo cell produces a nominal 3.7 V so a battery pack will be 3.7 V, 7.4 V, 11.1 V, etc., unless it includes a regulator or converter.

Russell.

Sorry, it's one of these. It yields 4.99V so it must have a regulator.

https://goo.gl/images/rpvXRQ