Have you ever been curious what your generator or inverter waveform looks like? I have and the question has been asked on this forum several times. I have a new to me, recently calibrated Fluke 41B power analyzer. I will be testing various sources and posting them here. The first picture will be my test setup. Following that will be wave form of utility power mainly for reference. Others will follow as time permits. Recently add at bottom of page: Onan 5500Test Setup:Utility Waveform/THD/Text:More to follow.

Next up is a Xantrex ProWatt SW2000Wave:THD:TextThis is a very good waveform and low THD!

What is load on the Prowatt? Space heater, microwave, air conditioner?What a great little tool :)

Several years ago (Well more than 2) the American Radio Relay League Inc published an article on just this in QST. You need membership or a subscribing library to read the article. It showed several differnet generators including some nice inverter jobs (Nice clean sine waves) some "Contractor" MOdels (Scary) some reduced (1200 or 1800 RPM engine models (Nice) They also did inverters (MSW v/s TSW and assorted models there too)Interesting to look at the 'scope traces.

smkettner, the load was 600 watt resistive heater. The numbers didn't change much with or without the resistive load.

AC (alt current) Waveforms and THD for gens and inverter

MEXICOWANDERER
Explorer
Jul 18, 2016
Kudos!
CJW8
Explorer
Jul 18, 2016
Next up is a Xantrex ProWatt SW2000
Wave:

THD:

Text

This is a very good waveform and low THD!
time2roll
Nomad
Jul 18, 2016
What is load on the Prowatt? Space heater, microwave, air conditioner?

What a great little tool :)
wa8yxm
Explorer III
Jul 18, 2016
Several years ago (Well more than 2) the American Radio Relay League Inc published an article on just this in QST. You need membership or a subscribing library to read the article.

It showed several differnet generators including some nice inverter jobs (Nice clean sine waves) some "Contractor" MOdels (Scary) some reduced (1200 or 1800 RPM engine models (Nice)

They also did inverters (MSW v/s TSW and assorted models there too)

Interesting to look at the 'scope traces.
CJW8
Explorer
Jul 19, 2016
smkettner, the load was 600 watt resistive heater. The numbers didn't change much with or without the resistive load.
pianotuna
Nomad III
Jul 19, 2016
Hi CJW8,

Thanks for taking the time to do this!
CJW8
Explorer
Jul 19, 2016
This a Kipor Generator. It is a 2000 watt inverter generator, about 8 years old. It is mostly used as a backup to the installed RV generator if I want to charge the batteries via the converter and don't want to run the main generator for less than a 1100 watt load. This generator was purchased as a less expensive alternative to the Honda and has served me very well. It has a very good waveform and low THD.
Waveform:

THD:

Text:
time2roll
Nomad
Jul 19, 2016
Yes resistive load is easy.
LittleBill
Explorer
Jul 19, 2016
if you can get that meter on a harbor freight 7k genny i would be thrilled to see it.
MEXICOWANDERER
Explorer
Jul 19, 2016
My KATO provides the least distortion I have ever seen in a generator. A good voltage regulator like a Delco H9000 suppresses field feedback ringing and KATO's secondary exciter winding includes a fourth phase. The secondary stator has about 150% of the laminations and double the wire. Even with all the chargers going, and then field collapse when switching off (500 amperes), THD is less than I measured with Southern California Edison 300 ampere 480 volt three phase service. Their generators are great but transmission and distribution transformers coupled with other user's line noise degraded the signal. But then again I am fussy.