Power Inverter A/C Power Voltage Quality - Oscilloscope Display

[emiddio]

I was curious about my 2023 jeep gladiator back seat Power Inverter Voltage; when I used simple V measurement tools,
a multimeter or a LED V only meter I saw strange results;

So hooked up oscilloscope - pics of no-load V shape, and 200W light bulb load V shape

;

No mention of Voltage quality in the owners manual - this is about as high a total harmonic distortion inverter as one could design;

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[ttn333]

I would't be charging my sensitive electronics from those outlets.

 

[jav_eee]

what does this mean for us dummies?

 

[evoarie]

Are you testing only the outlet? Would the usb ports be any different?

 

[chorky]

what does this mean for us dummies?

the opposite of a pure sine wave inverter. In other words, very bad news for sensitive electronics. If I knew this I would not have used that inverter to test my starlink mini. Hmm.... Pretty surprising, but also not surprising. I wonder if the one in the bed is any better for those who have that. But the factory inverter can be had for a couple hundred bucks I think which is very cheap compared to a high quality unit.

 

[ShadowsPapa]

Most "sensetive electronics" will have their own power supply. It would be fine for a laptop, phone, tablet, even many small TVs that have their own power supply that can handle that sort of thing (because they deal with DC anyway)
You don't feed electronics directly and once it's stepped down and filtered, they see DC - although likely not ripple-free.
Not sure what anyone would be using it for that would be all that critical anyway - most of our electronics will be 12v powered from the vehicle and not an inverter.

Has anyone shown any electronics to be damaged, or that would simply not operate off these cheap inverters?
Just curious.

 

[Radio Guy]

the opposite of a pure sine wave inverter. In other words, very bad news for sensitive electronics. If I knew this I would not have used that inverter to test my starlink mini. Hmm.... Pretty surprising, but also not surprising. I wonder if the one in the bed is any better for those who have that. But the factory inverter can be had for a couple hundred bucks I think which is very cheap compared to a high quality unit.

I see 400w “pure sine wave” inverters new under $70. There is no excuse for a square wave piece of crap considering what we paid.

 

[Mr._Bill]

It's not the greatest, but most items will run off the power it supplies with no issues. I use it to charge the compressor that I use to power the fridge (and fill the tires).

1200 Peak Amp Automotive Jump Starter, Portable Power – 10W USB Port, 500W Inverter, 120 PSI Air Compressor https://a.co/d/0fCcnFCs

I have an inverter I bought 11 years ago for $33. I used it to run my laptop in the truck. It was the 400 watt version of this.

Wagan EL2401-5 150W SmartAC USB+ Inverter with 5V 2.1A USB https://a.co/d/01zEU6fj

 

[MrBones]

Wouldn't be concerned unless I wanted to run a 120 V AC motor or something powered by a 60 Hz conventional transformer (Like a wall wart). The first thing most laptop or phone chargers will do is convert to a square wave before filtering to DC.

 

[Master_Cylinder]

Oh boy, is that dirty!

 

[emiddio]

In October 2023 I bought a 500 watt pure sine wave inverter from Amazon for close to $50;
That's 100 watts more than the gladiator 400 watt;

Attached is a Oscilloscope image of the Voltage - look at the Yellow plot, ignore the purple/blue - was testing something not

relevant to this discussion;

 

[ShadowsPapa]

or something powered by a 60 Hz conventional transformer (Like a wall wart).

Those are fine as well because it's not just a transformer. I've plugged in those "conventional transformers" and been fine - laptop, tablet, and so on)
They are more inside than a transformer. Show me one that puts out AC.
I even ran a cheap "tire inflater" from mine - it's got a motor in it that drives a small, cheap compressor (I use it for the air bags) and my mattress inflater works fine from it.

There's so very little that run on low voltage AC these days - your "wall warts" put out DC.

I go back to my original question - and all I get is speculation, nothing concrete - has anyone actually had any trouble or had anything damaged or not work?
So far it's just "no, but............" and that doesn't count.

 

[emiddio]

Are you testing only the outlet? Would the usb ports be any different?

I was testing the 115 V AC inverter 60 Hz output only; USB is not related to this discussion;

 

[fourfa]

has anyone actually had any trouble or had anything damaged or not work?

certainly - Ecoflow River 2 Max power station goes haywire with error codes and needs to be rebooted every time I try powering it from either the cab or bed outlet. Learned not to do that pretty quick

 

[ShadowsPapa]

In October 2023 I bought a 500 watt pure sine wave inverter from Amazon for close to $50;
That's 100 watts more than the gladiator 400 watt;

Attached is a Oscilloscope image of the Voltage - look at the Yellow plot, ignore the purple/blue - was testing something not

relevant to this discussion;

For 50 bucks, I question how long or how well it would actually handle 500 watts. You truly get what you pay for.
What does your pattern look like with a true load on it- say 400 watts or better?

I have a double-conversion pure sine wave UPS for my wife's quilting and embroidery machines - research into that topic led me straight away from low cost units. (dealing with the power for our network equipment before I retired gave me a head start into that research, and what was quality vs. - yeah, it's fine without a big load types of equipment.
My finding was - a quality inverter isn't cheap and a cheap inverter isn't quality when under load.
So I'd be interested in seeing how that pattern looks, the clean peaks and valleys, under heavy load. That's the tell.

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