user32464: I've been trying to make a wattmeter using arduino but cannot find the shield I need to buy to put onto my arduino to make it. There are no such parts in the Arduino Store and online the best I could find is this. This measures the arduino's energy consumption, however, not other things. I am really new at this and thoroughly lost. I would be really glad if someone could help me with this problem :)

user19013: You will need an Ampere meter and a Voltmeter. Watts is Volt * Ampere.
There are logic level compatible units out there for ampere meters ranging from a few mA to at least dozens of Amperes.
Also for voltmeters there are several logic level compatible units available, to plug in your project.
The rest is math. (Watts = A * V ) 

32464: <p>I've been trying to make a wattmeter using arduino but cannot find the shield I need to buy to put onto my arduino to make it. There are no such parts in the Arduino Store and online the best I could find is <a href="http://www.robotshop.com/en/energy-monitor-shield-arduino.html?gclid=CJD6jtrgiNMCFQmqaQody_0CPQ" rel="nofollow noreferrer">this</a>. This measures the arduino's energy consumption, however, not other things. I am really new at this and thoroughly lost. I would be really glad if someone could help me with this problem :)</p>
 19013: <p>You will need an Ampere meter and a Voltmeter. Watts is <code>Volt</code> * <code>Ampere</code>.</p>

<p>There are logic level compatible units out there for ampere meters ranging from a few mA to at least dozens of Amperes.</p>

<p>Also for voltmeters there are several logic level compatible units available, to plug in your project.</p>

<p>The rest is math. (Watts = A * V ) </p>
