Using a 300w Sine Power Inverter

Trying to use this 300w power inverter to get a faster charge in my car. The inverter charges my Jackery just fine at a higher rate than normal. When I try to charge the Bluetti EB3A in the car with this inverter it runs up to 80-110w and then resets to 0 and starts again. It keeps doing this over and over. I watched a guy on You Tube charging an EB3A with this same Bestek inverter working just fine. Not sure what the problem might be.

You may want to start with determining what type of inverter you have. There are 2 types of inverters, Pure Sine (wave) and Modified Sine. Pure sine inverters are more expensive and give a near perfect 60hz sine wave. Most electrical/electronic devices will never know the difference between the main power grid at 60hz and a pure sine inverter. A modified sine inverter however is a less expensive alternative to the pure sine, its cheaper to produce and has a more “Noisy” 60hz signal. Power bricks can sometime be finicky about noisy 60hz sine waves. its possible that the Bluetti power brick just wont work with that particular inverter. I have also seen cheap chinese knockoffs that claim to be pure sine inverters but they aren’t.

To add to what doecliff said, heres some images of a Pure Sine wave, compared to a modified sine (The industry calls it a modified sign wave, but it’s actually a modifed square wave).
A lot of electronics depend on the smooth signal seen by a pure sign wave. The modified square wave can be harsh for some electronics. I have a couple of Bestek inverters, but mine are Pure Sign wave, but I know they also sell modified sign wave also.

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The main reason it won’t charge may be the unstable output of your inverter.
Please try to set EB3A to silent mode without any loaded devices and try to see if it will improve.

This is the inverter I bought. It was recommended by a guy on You Tube who tested it on a Buletti EB3A. But he had better results. It works with a Jackery I have. I will try your suggestion and see what happens. Thanks for the help. So it doesn’t specify “pure” sine, is that a bad indication? I tried the silent mode and it did work longer, anywhere from 10 seconds to 33 seconds. It seems to reset at around 107 watts input every time. I guess the only way to test it would be a different inverter, possibly a different manufacturer. ?? I am going to buy a 400W pure sine inverter. Should be here tomorrow and I will do some testing and let you know how it goes.

I have a small Bestek I’ve keeped in my truck for 4 or 5 years, just in case. Other than a initial quick test, I’ve seldom used it, if at all. The colors are swapped, but it’s the same model number as yours.
I tried it with my EB3A at 50% capacity. In silent mode it worked. I ran it for a few minutes with no issues. The input on the EB3A showed it bouncing between 100 and 108 watts.
However, when I switched to standard mode, it would try to start, then stop, repeatedly. Sounds similar to your issue.
I also have a 500W Bestek I seldom use. When I tried it, I got the same results. Works only in silent mode.
The 300W is 110v AC, which at first I thought might be the issue since it would drop down as low as 108.2v, however, the 500W is 120v AC, and while it dropped, not as much as the 300W.

The only other small inverter I had for testing is a Ryobi 300W that uses the 40V batteries. It charged the EB3A in both silent (~100w) and standard (~150w) mode just fine.

I don’t think I’ll be buying any more Bestek inverters.

Here’s the Ryobi inverter. I use the 40v batteries for my weed eaters, chain saw, pump, etc…

Here’s my 300W Bestek. Same model as yours.

I’m using a Victron PSW 375W inverter from my 4x4 aux battery (engine on) to charge both my AC70 & AC180 on silent setting which is below 300W of power draw. Both work very well and you definitely need to use a PSW inverter. Longer to charge than from grid, but heaps better than the 8A from a cig socket. P.S. I already had the inverter and the extra capacity also means the Victron doesn’t work as hard as it’s around 75% of it’s rated output.

The size inverter I am using only works on the lower charge mode as standard Bluetti charge rates for bigger units exceed the capacity of the inverter. The EB3A is < 300W max charge, therefore a reasonable quality 300W PSW inverter should work.

I bought this Cobra 400w inverter. It is highly rated and more expensive, which possibly means nothing. Tried it with the same results. It seemed to run a little longer with the Bluetti in silent mode, but not much. I am done wasting money on this. It has been a very sunless winter her in Oregon and I was just trying to charge the Bluetti a little faster in the car. Back to regular slow charging now. Sun is supposed to be out next week, possibly. I can charge my cell phone faster in my car with this inverter.
Both of these inverters are supposed to be Pure Sine Wave inverters. I will try charging my Jackery 1500 in the car with the new inverter. I tried the Cobra on the Bluetti on more time and I set it to silent and then turn ECO on and it reset a couple times and then continued to charge for 8 minutes and I turn it off. I will work with it some more tomorrow.