Any electrical engineers? A couple of DC-to-AC power inverter questions...

[JasonSnake]

Alright, so I am researching to see which inverter to buy. So far I am leaning towards buying an inverter that uses "pure sine wave" - which is what I would want to use to provide clean power to all my devices and small appliances I will use when I go on a road trip, camping, etc. I've also read that the cheaper "modified sine wave" inverters will shorten the life of electronics.

Question 1: Why is it that on mod. sine wave inverters, they come with 120v outputs, but on pure sine wave, they come with just 110v output? Does it have to do with efficiency?

Question 2: pure vs modified, same output wattage rating, which will draw more power from the battery powering the same devices?

Question 3: Which brands do you recommend I buy, something that is at least 2000 watts?

 

[VerySneaky]

I'm not electrical, but have some experience with selection of these:

Question 1: Why is it that on mod. sine wave inverters, they come with 120v outputs, but on pure sine wave, they come with just 110v output? Does it have to do with efficiency?

Yes, I believe this has to do with efficiency, you can get more peak power out of a modified, but the pure is a more fluid waveform that doesn't make things run funny (i.e. that buzz in a cheap stereo)

Question 2: pure vs modified, same output wattage rating, which will draw more power from the battery powering the same devices?

Pure will probably draw more power, since if you hook both up to an O-scope, a pure inverter will give you a fluid sine wave, where a modified will be a square wave with multiple peaks. Mathematically, if you remember high school calculus, to find the area under a curve (in this case, would give you the amount of power/wattage) you can either integrate the known function, or sum multiple areas at different points over the curve with a given base length. Given that the pure wave is a continuous function, the area will always be greater than a modified wave signal. At least until the number of square waves per period increases to a high enough number that the difference in area is negligible.

Question 3: Which brands do you recommend I buy, something that is at least 2000 watts?

Pure inverters are usually more expensive. That being said, you can never go wrong with Tripp-Lite.

 

[Mr. Mach-ete]

Get yourself a true RMS electrical meter and test the outputs.

 

[JasonSnake]

I'm not electrical, but have some experience with selection of these:


Yes, I believe this has to do with efficiency, you can get more peak power out of a modified, but the pure is a more fluid waveform that doesn't make things run funny (i.e. that buzz in a cheap stereo)

Pure will probably draw more power, since if you hook both up to an O-scope, a pure inverter will give you a fluid sine wave, where a modified will be a square wave with multiple peaks. Mathematically, if you remember high school calculus, to find the area under a curve (in this case, would give you the amount of power/wattage) you can either integrate the known function, or sum multiple areas at different points over the curve with a given base length. Given that the pure wave is a continuous function, the area will always be greater than a modified wave signal. At least until the number of square waves per period increases to a high enough number that the difference in area is negligible.

Pure inverters are usually more expensive. That being said, you can never go wrong with Tripp-Lite.

Sweet, thanks for the info! After looking through Amazon, I have my eyes set on this one:
http://www.amazon.com/dp/B0065M5NU4...UTF8&colid=9DBBQOBZGTWY&coliid=I3V0EZAD7RDS1X

Looking at some youtube videos on it, I am impressed by it.
https://www.youtube.com/watch?v=11QDoG3s3ro

Get yourself a true RMS electrical meter and test the outputs.

Being that everything is made in China, even "Heavy Duty" inverters, will need to do this for sure