# Measuring Power and Capacity

If you’re measuring power or battery capacity,  measuring current will likely be one of the measurements you include.   Fortunately, there are several devices on the market to help you to accomplish this.

I’ve played with a few and the articles listed below will introduce you to them.

## ACS712 Current Module User Manual

This manual for the ACS712 Current module provides an overview, specs, connections and the datasheet for the Allegro chip upon which is based.

The module comes in three flavors: 5A, 20A and 30A.

Its not an overly complicated device. You just need to know how to interpret it.

## ACS712 Current Module Arduino Tutorial

Using an ACS712 Current Sensor with your Arduino is really simple stuff.

## AC Current with an ACS712 Tutorial

If you’re interested in how much power your AC powered widget is using, you will need to measure the current.

This tutorial shows you how to use your Arduino with and ACS712 to do just that.

There’s a little basic theory here, but not too much. Just enough to get you started.

## INA219 Arduino Current and Voltage Sensor Tutorial

This little device measures both current and voltage. It therefore gives you the ability to measure power.

The current range is up to 3.2A.

Voltages up to 26 volts can be measured as well

## TA12-100 Arduino AC Current Sensor Tutorial

You are able to measure AC current by passing a wire through the center of the current transformer and measuring the voltage across a resistor place at the transformer output.

This device is good for up to 5A.

The tutorial shows how to hook it up and make use of it immediately.

## MAX471 Arduino Current Sensor Tutorial

Learn how to put this 3 amp current sensor to us in your next project.

The MAX471 is a high side sensor that is easy to implement in code.

Includes drawings, tutorial and sketch.

## MAX471 Arduino Power Meter

Measuring power requires at least two of the three variables found in Ohms law.

The MAX471 measures both current and voltage.

With these values, you can measure power