BESTEK 300W Power Inverter DC 12V to AC 110V Pure Sine Wave Inverter with 4.2A Dual Smart USB Ports Car Adapter

by people ...

BESTEK Advantage: America’s leading power inverter brand. Provides 300W continuous DC to AC power and 700W of peak power with 2 AC outlets and 2 USB charging ports
Smart Charging: the power inverter is equipped with 2 Smart USB charging ports, automatically detect your devices to deliver its fastest charge speed up to 2.4 amps per port/4.8 amps max
Most Compact and Lightweight: travel-sized and smart cooling fan makes it silent when running. The 26 inch cigarette lighter plug is convenient for you to plug directly into a cigarette lighter socket
Mufti Protection: built-in 40 amps fuse and full-protection with short-circuit, low-voltage, over-charge, over-voltage, over-load, over-temperature protection
What You Get: BESTEK 300W Power Inverter, User Manual, Our 18-month warranty and friendly customer service

Color:Pure Sine Wave BESTEK America’s Leading Power Inverter

• The highest average review rating of any power inverter brand. • Designed as a portable power inverter to power up multiple items and most major household appliances.

Upgraded 300W DC to AC Power Inverter

•A must-have for your road trips, vacations, outdoors, emergency kits and more. •Enjoy 4.8A dual Smart USB ports and 2 standard plug outlets for convenient charging on the road. Product Specification :

• Power (2 AC Outlets): 300W Rated, 360W Max, 700W Peak • Input Voltage: 12V DC, Output voltage: 110V~120V • Dual USB Port Output: DC 5V, 4.2A rated, 4.8A Max. Auto 0~2.4A*2 • Indicator: Green-operation, Red-shutdown • Over Voltage Shutdown: DC 15V-16V, Low Voltage Shutdown: DC 10V-11V • Dimensions are: 4.92 x 3.39x1.93 inch Optimal Use and Precautions:

• For DC12V ONLY, not applied for DC 24V and airplane use. • Please do not leave the Power inverter in the ON position while your car is off. • If the rated input of any connected AC devices exceed 150W, please use battery clamps to directly connect to your vehicle’s battery as most vehicles 12V ports are rated and fused for 150W. • Avoid placing the inverter into sunlight directly or next to heat-sensitive materials to protect inverter from getting too warm. • Caution! Not designed for high power electric devices such as hair dryers, electric heaters, curling irons, etc. Package List :

• 1 x 300W Power Inverter • 1 x User Manual

Product Reviews

Noisy output

The inverter has a fan that is always on. It’s ridiculously loud. You are not going to be sleeping in the same room with this thing on and running. When the inverter is on, it uses about 6 watts even if nothing is plugged into it. I tested the efficiency with a 43 watt load and got a 12 V side power reading of 61 W, efficiency of about 70%, which is not great.The output is 110 V which is OK for most applications.Then I decided to test how clean the output waveform actually is. And it turn out it’s extremely noisy. I made a 100 to 1 voltage divider (100kOhm to 1 kOhm) and hooked up my scope to it. It has crazy voltage spikes that are ginormous: (6V x 100 = 600 V) at a frequency of about 50 to 100 kHz.I’ve attached the scope traces of what my mains power outlet looks like and the waveform output of this piece of junk inverter.When you look at those traces remember that they were run through a 100x voltage divider.Also, i have not tested the USB outlets, but they must be noisy as well because they caused my phones touchscreen to go crazy when it is connected to them and charging.

BESTEK 300W POWER INVERTER.

3-1-15. I just received this inverter a few days ago! The ac outlets work great! I will definitely try it out on my next power outage! The only two things that I don’t like are the cigarette lighter plug has the cord directly wired without a fuse and the 40 amp fuse the unit has is inside soldered to it’s pc board. (see picture) That will make it hard to replace the fuse. Other than that the inverter is a great price and was shipped to me in 8 days! Update 11-5-16 (Warning) : The two USB plugs stay powered up all the time even if the power button is turned off. That could leave you with a dead car battery if you don’t unplug the inverter.

Almost good! Poorly thought out design.

Fan noise is too loud (probably about 65dB at 6 ft). I don’t understand Bestek’s design concept. Probably they tried to cut cost too much and ended up with a product with little value.1) Using plastic enclosure, very small heatsink inside. It cost just a little more to use metal enclosure for better heat dissipation. I think people would pay $60 or more for a quiet 300W pure sine inverter.2) Fan is running continuously off 12V, no temperature-speed control. Fan is much louder on 14V, i.e. while the car is running and charging battery.3) It draws 900 MA @ 12V (or 11W) without any load on the AC output.4) Why bother with USB ports? This is all about Pure Sine Inverter. I just want a good Inverter.5) This is a PWM high frequency design. Sine wave looks clean enough, but you can still see high switching frequency riding on the 60Hz on the Oscilloscope.

Not what it claims.

The cigarette lighter-only connection limits this to about 150 W without jerry-rigging the wires, which are too small for continuous 300 W, indicating that its true max operating design is closer to 150 W. Bypassing the connector and plugging in a 250 W light bulb the unit immediately tripped off, again a sign of it’s true design. When I looked at the output on an oscilloscope it looked like a slightly softened modified sine wave. The price and size are a bit high for a 150 W MSW inverter, regardless of what it claims. The color scheme looks racy though.

Considering the price I did not expect the AC output to be very “pure” but hoped it would at least be better than the “modified

Note: there are many models of BESTEK 12 VDC to 110 VAC inverters. This review covers only the BESTEK “300W Sine Power Inverter”, model MRZ3011HU-US.Distortion: This inverter is advertised as “pure sine wave inverter”BESTEK 300W Power Inverter DC 12V to AC 110V Pure Sine Wave Inverter with 4.2A Dual Smart USB Ports Car Adapter. Considering the price I did not expect the AC output to be very “pure” but hoped it would at least be better than the “modified sine wave” from most inexpensive inverters. I was quite surprised to see that the output is a very clean sine wave (see photo) with total harmonic distortion plus noise measuring less than 3.5% at 100 W output. The actual distortion may be considerably better than 3.5% as the measurement was the limited by the noise of the test equipment used. Distortion was only measured at 100 W output but the shape of the sine wave did not appear to change from no load up to 280 WattsStart-up: The AC output is very well behaved on start up when the inverter is powered on (see photo). There are no large transients and the AC output voltage ramps up smoothly over a period of approximately 400 ms. The start-up waveform is the same regardless of the load on the inverter.Regulation: The output voltage of the inverter was very well regulated. With 14 VDC input, the output voltage varied from 109.9 VRMS at no load to 108.9 VRMS with a load of 285 Watts. With a 100 Watt load the output voltage varied from 109 VRMS with 12 VDC input to 109.4 VRMS with 14.5 VDC input (see plots).Efficiency: With 14 VDC input and a 100 Watt load the efficiency of the inverter measured 88.4%. That is very good for an inverter with true sine wave output. Efficiency at full load drops slightly and measured 86.4% with a 285 Watt load and 13.1 VDC input.AC ground: The inverter AC output floats relative to the DC input. Neither the neutral or the ground of the AC outlet connects to the negative lead of the DC input. The ground pins of the two AC outlets are not connected to chassis ground or to each other.Sound level: The inverter has a fan that runs continuously when the inverter is on. I did not find the sound level objectionable when the inverter was on the floor of the vehicle and fan was facing away. For comparison, the fan in the inverter was approximately the same sound level as the vehicle heater/AC fan when it is set on “medium” speed.Other features: The inverter has a “NO/OFF” switch (see photo). It appears to function the same as an “ON/OFF” switch.Summary: the performance of the inverter is very good and it’s a great value for the price ($32.99).

A great value pure sine wave inverter, runs motors great!!

Great pure sine wave inverter! I have been using this with my solar set up for a couple of months now and it has worked out better than expected.

Five Stars

Works great!

Four Stars

it works my small devices with no problems

Five Stars

Well made. Would buy again. Came fast.

Good

Works on everything I have tried. The plug in with the cord is good, so that it will probably fit in any outlet.

Great product!

It works very well!! I use it all the time to charge my phone and laptop when on the road.

Works Very Well

I bought this to power up Christmas lights on my Corvette for the Christmas parade in our small town. The unit ran the lights and a tree mounted on the rear of the car very well.