Manufacturer | BESTEK |
---|---|
Brand | BESTEK |
Model | MRZ3011HU |
Item Weight | 1.4 pounds |
Product Dimensions | 8.1 x 5.3 x 2.6 inches |
Item model number | MRZ3011HU |
Is Discontinued By Manufacturer | No |
Manufacturer Part Number | MRZ3011HU |
Voltage | 12 Volts |
Wattage | 300 watts |
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BESTEK 300Watt Pure Sine Wave Power Inverter Car Adapter DC 12V to AC 110V with 4.2A Dual Smart USB Ports
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Free returns are available for the shipping address you chose. You can return the item for any reason in new and unused condition: no shipping charges
Learn more about free returns.- Go to your orders and start the return
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Return this item for free
Free returns are available for the shipping address you chose. You can return the item for any reason in new and unused condition: no shipping charges
Learn more about free returns.- Go to your orders and start the return
- Select the return method
- Ship it!
Return this item for free
Free returns are available for the shipping address you chose. You can return the item for any reason in new and unused condition: no shipping charges
Learn more about free returns.- Go to your orders and start the return
- Select the return method
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Purchase options and add-ons
Brand | BESTEK |
Recommended Uses For Product | Vehicle |
Power Source | 110v,Corded Electric |
Wattage | 300 watts |
Model Name | MRZ3011HU |
About this item
- BESTEK 300W PURE SINE INVERTERS designed for your devices that require careful protection, provide 300W continuous DC to AC power and 700W of peak power featuring 2 AC outlets and 2 USB charging ports, great for Christmas gift, charging string lights, laptop, speakers, camera, nebulizer, game console, kindle, iPad and other
- Equipped with 2 Smart USB charging ports, which detects your devices automatically to deliver its fastest charge speed up to 2.4 amps per port/4.8 amps max, and you can charge most phones and tablets simultaneously
- Unique vents and smart fan design make our 300W power inverter easier to dissipate heat, and cigarette lighter plug is easy to plug into a cigarette lighter socket
- Built-in 40 amps fuse and full protection against overheating, under and over voltage charging, short circuiting, overloads, and overcharging
- What You Get: 1*BESTEK 300W Pure Sine Power Inverter, 1*User Manual, 18-month warranty and customer service
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This Item BESTEK 300Watt Pure Sine Wave Power Inverter Car Adapter DC 12V to AC 110V with 4.2A Dual Smart USB Ports | Recommendations | dummy | dummy | dummy | |
Try again! Added to Cart | Try again! Added to Cart | Try again! Added to Cart | Try again! Added to Cart | Try again! Added to Cart | |
Price | -13% $49.99$49.99 Typical: $57.74 | -15% $39.99$39.99 Typical: $46.99 | -10% $26.99$26.99 Typical: $29.99 | $57.74$57.74 | $35.99$35.99 |
Delivery | Get it as soon as Sunday, Mar 31 | Get it as soon as Sunday, Mar 31 | Get it as soon as Sunday, Mar 31 | Get it as soon as Sunday, Mar 31 | Get it as soon as Sunday, Mar 31 |
Customer Ratings | |||||
Charging power | 4.3 | 3.6 | 4.1 | 4.3 | 4.5 |
Value for money | 4.5 | — | 4.1 | 4.5 | 5.0 |
Noise level | 4.3 | 5.0 | — | 4.3 | 4.1 |
For traveling | 4.5 | — | — | 4.5 | 3.6 |
Sold By | BESTEK. | E-POLAR | BESTEK. | BESTEK. | BESTEK. |
power outlets | 4 | — | 4 | 4 | 4 |
output voltage | 120 volts | 110 volts | 110 volts | 120 volts | 110 volts |
input voltage | 12 volts | 12 volts | 12 volts | 12 volts | 11 volts |
output power | 300 watts | 300 watts | 300 watts | 300 watts | 300 watts |
weight | 1.4 pounds | — | — | 1.4 pounds | 480 grams |
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Product Description
Designed for your devices that require careful protection
BESTEK Advantage
America's leading power inverter brand. Provides 300 watts continuous DC to AC power and 700 watts of peak power.
- Pure Sine Wave Power Inverter
- 2 AC Outlets
- 2 Smart USB Charging Ports
- Smart Cooling Fan
- Built-in 40 Amps Fuse
- High-quality Plastic Housing
BESTEK 300W Pure Sine Wave Power Inverter
[Pure Sine Wave] BESTEK Power Inverter with 2 USB ports and 2 AC outlet.For charging your iPad, please use the 2.1A USB port and keep the other USB port free. 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 cigarette lighter ports are rated for 150W. Do not use to power high power electric devices such as hair dryers, electric heaters, which might blow a fuse.
- Designed for your devices that require careful protection
- Detects your devices automatically
- Top Speed Charging
- Built-in fuse, Full protection
- Easier to dissipate heat
- Isolation Voltage Protection
- Durable Cigarette Lighter
- Ultra Compact
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Pure Sine WaveDesigned for your devices that require careful protection.Provides sine wave output which is more stable and can be applied to the curling iron,hair straightener and the electric toothbrush within 300W designed for your devices. |
2 AC Outlets And 2 USB Charging PortsEquipped with 2 Smart USB charging ports, which detects your devices automatically to deliver its fastest charge speed up to 2.4 amps per port/4.8 amps max, and you can charge most phones and tablets simultaneously. |
Smart Cooling FanSmart cooling fan system makes the car power inverter very silent when operating,and the fan runs faster when the device gets warmer or output power exceeds 70W. It's normal for the inverter to become warm to the touch while you are using it, avoid placing the inverter in direct sunlight. |
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Durable Cigarette LighterDouble durable springs each side for tight mount stable and electrical safety.The lighter socket is resistant to up to 5000 times of insertion and extraction, can plug into almost all vehicles. |
Isolation Voltage ProtectionSafe charging design provides protection against, overheating, under and over voltage charging, short circuiting, overloads, and overcharging. |
Car Becomes RVWith our car power inverter, you can use most of home appliances in your car in the open air, such a watching TV, playing games, give you the experience like being in an RV. |
BESTEK 300W power inverter(red) | BESTEK 300W Car Power Inverter, with USB-C PD 20W | BESTEK 200W power inverter(black) | BESTEK 500W Pure Sine Wave Power Inverter (Red) | BESTEK 75W power inverter(black and silver) | |
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Customer Reviews |
4.5 out of 5 stars
31,600
|
4.5 out of 5 stars
174
|
4.5 out of 5 stars
4,187
|
4.5 out of 5 stars
2,759
|
4.4 out of 5 stars
4,359
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Color | Red | Red | Black | Red | Black and silver |
Power | 300W | 300W | 200W | 500W | 75W |
Feature | Smart cooling fan | Smart Coling Fan | ETC and Smart cooling fan | Smart cooling fan | Smart cooling fan |
isolation voltage protection | ✓ | ✓ | ✓ | ✓ | ✓ |
USB Port | 4.2A Dual USB | 4.2A Dual USB | 4.2A 4 USB | 4.2A Dual USB | 3.1A Dual USB |
Dimension | 4.8 x 3.1 x 1.9 inches | 5.5 x 4.6 x 2.2 inch | 6.2 x 3.3 x 1.4 inches | 8.7 x 4.3 x 2.4 inches | 5.5 x 2.4 x 1.6 inches |
Product information
Technical Details
Additional Information
ASIN | B07KQ4Q2L5 |
---|---|
Customer Reviews |
4.5 out of 5 stars |
Best Sellers Rank | #4,687 in Automotive (See Top 100 in Automotive) #19 in Power Inverters |
Date First Available | September 21, 2018 |
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Customer reviews
Customer Reviews, including Product Star Ratings help customers to learn more about the product and decide whether it is the right product for them.
To calculate the overall star rating and percentage breakdown by star, we don’t use a simple average. Instead, our system considers things like how recent a review is and if the reviewer bought the item on Amazon. It also analyzed reviews to verify trustworthiness.
Learn more how customers reviews work on AmazonCustomers say
Customers like the performance and appearance of the power inverter. For example, they mention it works great, it charges their laptop and it looks awesome. Some are happy with the value and size. That said, opinions are mixed on noise, quality, charging power, and temperature.
AI-generated from the text of customer reviews
Customers like the performance of the power inverter. For example, they say it works great, barely uses any power, and has no issues. Some say the battery worked fine for simple dc loads. Overall, most are satisfied with the performance and recommend the product to others.
"...Works really well at powering my xbox and tv so I can game in the truck. Worth the price." Read more
"...so all I need is an inverter of modest capacity but this one works like a bigger one...." Read more
"...A week later it is working great. We use the fan overnight. The inverter seems to have plenty of power for my application...." Read more
"...my initial impression is that the inverter is a perfectly serviceable pure sine wave inverter that is far superior to modified sine wave inverters..." Read more
Customers have mixed opinions about the quality of the power inverter. Some mention that the build quality seems very good overall, and it holds up well. They also say it's very reliable and strong enough to run laptops. However, others say that it malfunctioned and completely failed to perform as advertised. They say that the unit is not serviceable, and not good for the longevity of the unit.
"Only inverter I have had ever that lasts and doesnt give up. Works really well at powering my xbox and tv so I can game in the truck. Worth the price." Read more
"...output is strong and (apparently, as judged on my Kill-A-Watt meter) stable and clean...." Read more
"...owning this product for a few months, when I tried to use it, it was malfunctioning...." Read more
"...surprised and impressed with this unit’s design excellence and manufacturing quality...." Read more
Customers like the appearance of the power inverter. They say it looks sleek and is quiet. Customers also appreciate the good design and form factor. However, some customers have reported that the inverters draws too much current at idle.
"...The power it outputs is quite acceptable and makes my home UPSs (which are normally very sensitive to power quality) happy...." Read more
"...; just pleasantly surprised and impressed with this unit’s design excellence and manufacturing quality...." Read more
"Perfect." Read more
"was an awesome simple little unit,I have an older ride with a loose cigarette connector ,wiggled the cigarette connector too many times in a row..." Read more
Customers like the value of the power inverter. They say it's a good value, especially if you can get it on sale, and a huge cost savings.
"...Worth the price." Read more
"...Worth every penny...." Read more
"...This is a quality product at a reasonable price." Read more
"This thing is worth every penny… We go camping all the time and use this to charge all our devices and run any electronics needed… It’s probably the..." Read more
Customers like the size of the power inverter. For example, they say it's perfect for their application, small for its capacity, and super portable. Some mention it'll run a small TV in an RV. That said, most are happy with the size and design.
"...The 12V plug is spring-loaded and fits snugly into the receptacle.A small fan comes on as needed and isn't terribly loud...." Read more
"...It's also compact, solidly built, and very reasonably priced...." Read more
"...The inverter is behind the display but not enclosed and has plenty of room all around it. The fan isn't choked for air...." Read more
"..."The 12V plug is spring-loaded and fits snugly into the receptacle...." Read more
Customers are mixed about the noise of the power inverter. Some mention that it runs pretty quiet, almost not noticeable. The buzz noise is not bad, and the fan isn't too loud. They like that it did not make their TV hum. However, others say that it's a bit noisy, but it really doesn't bother them much. Some say that the little fan is louder than expected to be, and that it might generate RF noise at higher frequencies. The inverters did not give an audible alarm for low voltage, and are incredibly inconvenient.
"...power hogs; this one with its pure-sine wave output appears smooth and quiet (electrically and sound-wise) and appears to use very little power..." Read more
"...and preferably accessible from the outside of the unit is incredibly inconvenient...." Read more
"...Quiet and does not get very hot. I used it to power an oxygen concentrator in my Tesla - it worked well...." Read more
"...The Bestek 300W inverter fits the bill nicely. It's quiet (some inverters emit a high pitched squeal), and the fact that it's PSW..." Read more
Customers are mixed about the charging power of the power inverter. Some mention that the power it outputs is quite acceptable, has plenty of power, and seems clean. However, others say that the high no load current, and the low voltage under any load.
"...The output is strong and (apparently, as judged on my Kill-A-Watt meter) stable and clean...." Read more
"...though it can technically do 300w, it's of no use if the voltage doesn't stay above 100. But not sure if i just received a bad unit or something...." Read more
"...We use the fan overnight. The inverter seems to have plenty of power for my application...." Read more
"...The power it outputs is quite acceptable and makes my home UPSs (which are normally very sensitive to power quality) happy...." Read more
Customers are mixed about the temperature of the power inverter. Some mention that it doesn't seem to get hot, while others say that it runs a little warm. The fan is heat activated and cycles on and off.
"...it runs quietly and stays cool as a cucumber. Make that a fresh refrigerated cucumber from where?..." Read more
"...4/5 stars due to the fan issue...." Read more
"...Working great and nothing gets hot." Read more
"...this before I bought it on Amazon where others said the cooling fan is a weak spot in this inverter. Now I know why...." Read more
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It seems to do everything right. I like it.
A week later it is working great. We use the fan overnight. The inverter seems to have plenty of power for my application. I will keep updated if the inverter quits or damages my fan controller. It says it is pure sine wave... I have no way to test, but I trust it is.
This inverter is just such a "pure sine wave" model, and outputs a rather nice sine wave (see attached photos). It's a pretty typical sinusoidal wave with a frequency of 59.5 Hz (utility power in North America is 60 Hz, and 59.5 Hz is perfectly acceptable). The peak-to-peak voltage of my unit was 158 V, which corresponds to an RMS voltage of 111 V. This is within the nominal range of 110-120V found in North America, and should be universally compatible with any device.
If one zooms in on the waveform, one can see the 24.3 kHz switching steps of about 10 V that the device produces. This is an unavoidable consequence of converting DC to AC, and it's at such a high frequency that it should have no effect whatsoever on any device connected to it. Ideally, I'd like to see some sort of low-pass filter applied to the output of the inverter to filter that 24.3 kHz noise, but then I remembered that this is a $40 item and that such noise isn't going to affect anything.
The 12V cord is thick and looks to be the 11 AWG (4mm^2) cable Bestek uses for their battery clamps-to-lighter-socket set. This is perfectly fine for this power level. The 12V plug is spring-loaded and fits snugly into the receptacle.
A small fan comes on as needed and isn't terribly loud. Still, it comes on periodically when the unit is idle with no load attached, for which I'm deducting one star from "noise level".
The quality of the circuit board on my unit looked fine, with no assembly problems, bad solder joints, etc.
There's two small downsides that I've noticed:
1. The fuses are inside the unit, require its disassembly (pop off the rubber feet, unscrew the four screws there, then unscrew the circuit board inside from the supporting posts), and the fuses (two 25A automotive "Mini" size fuses wired in parallel) are soldered to the board. Again, I realized it's built to a price point, but having the fuses soldered to the board rather than being in sockets and preferably accessible from the outside of the unit is incredibly inconvenient. Having an in-line fuse in the cord or 12V lighter plug would be fine as well, but having them be internal and soldered down is annoying.
2. The cord is not detachable. While Bestek offers a nice battery clamps-to-lighter-socket set, it sure would be handy to simply be able to unplug the lighter cord and replace it with a cord with battery clamps that's connected directly to the unit. It'd also make the unit more compact for storage.
In short, my initial impression is that the inverter is a perfectly serviceable pure sine wave inverter that is far superior to modified sine wave inverters at only a slight price premium. While it's bulkier than some other inverters for its power level, it's not excessively large. The power it outputs is quite acceptable and makes my home UPSs (which are normally very sensitive to power quality) happy. The lack of easily-replaceable fuses is annoying enough to warrant the deduction of a star; it wouldn't be hard for them to have a higher-rated internal fuse that's there to prevent fires in the event of a major fault and a fuse for the rated current in-line with the cable or in the plug to prevent overheating in the event of a normal overload. Other than the fuse issue, I'm perfectly happy with the unit so far.
Reviewed in the United States on May 16, 2019
This inverter is just such a "pure sine wave" model, and outputs a rather nice sine wave (see attached photos). It's a pretty typical sinusoidal wave with a frequency of 59.5 Hz (utility power in North America is 60 Hz, and 59.5 Hz is perfectly acceptable). The peak-to-peak voltage of my unit was 158 V, which corresponds to an RMS voltage of 111 V. This is within the nominal range of 110-120V found in North America, and should be universally compatible with any device.
If one zooms in on the waveform, one can see the 24.3 kHz switching steps of about 10 V that the device produces. This is an unavoidable consequence of converting DC to AC, and it's at such a high frequency that it should have no effect whatsoever on any device connected to it. Ideally, I'd like to see some sort of low-pass filter applied to the output of the inverter to filter that 24.3 kHz noise, but then I remembered that this is a $40 item and that such noise isn't going to affect anything.
The 12V cord is thick and looks to be the 11 AWG (4mm^2) cable Bestek uses for their battery clamps-to-lighter-socket set. This is perfectly fine for this power level. The 12V plug is spring-loaded and fits snugly into the receptacle.
A small fan comes on as needed and isn't terribly loud. Still, it comes on periodically when the unit is idle with no load attached, for which I'm deducting one star from "noise level".
The quality of the circuit board on my unit looked fine, with no assembly problems, bad solder joints, etc.
There's two small downsides that I've noticed:
1. The fuses are inside the unit, require its disassembly (pop off the rubber feet, unscrew the four screws there, then unscrew the circuit board inside from the supporting posts), and the fuses (two 25A automotive "Mini" size fuses wired in parallel) are soldered to the board. Again, I realized it's built to a price point, but having the fuses soldered to the board rather than being in sockets and preferably accessible from the outside of the unit is incredibly inconvenient. Having an in-line fuse in the cord or 12V lighter plug would be fine as well, but having them be internal and soldered down is annoying.
2. The cord is not detachable. While Bestek offers a nice battery clamps-to-lighter-socket set, it sure would be handy to simply be able to unplug the lighter cord and replace it with a cord with battery clamps that's connected directly to the unit. It'd also make the unit more compact for storage.
In short, my initial impression is that the inverter is a perfectly serviceable pure sine wave inverter that is far superior to modified sine wave inverters at only a slight price premium. While it's bulkier than some other inverters for its power level, it's not excessively large. The power it outputs is quite acceptable and makes my home UPSs (which are normally very sensitive to power quality) happy. The lack of easily-replaceable fuses is annoying enough to warrant the deduction of a star; it wouldn't be hard for them to have a higher-rated internal fuse that's there to prevent fires in the event of a major fault and a fuse for the rated current in-line with the cable or in the plug to prevent overheating in the event of a normal overload. Other than the fuse issue, I'm perfectly happy with the unit so far.
Output voltage regulation is excellent; I tested it from 10 VDC in to 14.4 VDC, and it sags only a little, from 114 VAC RMS down to 110 VAC RMS. Your attached appliances will never know the difference.
Mine clocked in at 59.99 Hz from 14V in, 60.02 Hz at 10V in; again, your appliances will never know the frequency difference, as frequency regulation is excellent. I ran FFT on the sinusoidal output to check harmonics; the highest was the 4th at 40 dB down. The sinusoidal output is very pure, very clean.
Ever the curious one, I took a look inside. Four TO-220 nicely heat-sinked switching FETs (presumably) operating in tandem to drive a series toroidal inductor/capacitor low-pass (shaping) filter. The switching frequency is right at 25 kHz, and pulses range from 760 nS up to whatever width is required to maintain the waveform, depending on load and phase angle. I measured this on the driven side of the L/C output filter, see pics.
This unit does generate some hash in the AM radio band, no surprise. It might generate RF noise at higher frequencies including the HF bands (I didn’t test that; hey, this is a free product review), but if you’re a ham radio operator, you’re probably running off of batteries if you need low noise. It’s probably within FCC Part 15 unintentional radiator limits; I didn’t test conducted or radiated emissions either.
I bought this unit because my DJI drone battery chargers (3 different drones, 3 different chargers) refused to recognize my older “modified” sine inverters as providing useful AC power. I don’t blame them; whoever named it “modified sine wave” definitely worked in marketing, not engineering. And they’re rude. All of my DJI chargers work fine with this Bestek Sine unit, and why wouldn’t they? They’re being fed a swell, 60-Hz sine wave, just like at home.
I highly recommend this unit. It’s internally fused, so you’ll have to do some soldering if you pop the fuse. You need to remember that 300 watts at 120 VAC is only 2.5 amps, but at your 12V input, it’s 25 amps assuming 100% conversion efficiency. Assuming a realistic conversion efficiency north of 80%, that’s 30 amps.
Many automotive cigar lighters are fused at 10A. Never replace a 10A fuse with a 30A fuse to keep it from popping. There’s a reason auto manufacturers made that a 10A fuse, and it’s the wiring between your battery/charging system and the cigar outlet. Don’t turn your car into a crispy critter by upping any fuse, certainly not this one. If you need 300W, either make sure your car or truck cigar lighter fuse can handle the 30A, or buy some healthy alligator clips and attach this unit, via dual inline 30A fuses, directly to your battery. It’s also worth noting that most automotive alternators will produce about 50 amps at idle.
I plugged three 100W incandescent bulbs to my Bestek 300 W Sine Wave inverter and read 253 watts on my handy Kill A Watt P3 test instrument. I attached it to my 36 AH fishing-motor battery and ran it for several minutes with no discernible heating of the inverter casing or the air at its vents. I also attached my iPhone to the USB output, and the USB outputs on this unit are indeed wired to charge iPhones (proper resistor-divider values on the USB data pins). It measured 1.56A into my iPhone, probably current limited by the phone, for a nice fast charge.
The fan seems to have two speeds: modest and off. When operating, it’s fairly quiet. As you might expect, whether the fan runs or not is not so much affected by load; most of the power dissipated in switch FETS is related to moving charge and intermediate resistance value during transitions, not to Rdson losses. Assuming these are FETs (highly likely).
I tested low-voltage and overvoltage cutoff points, and found that the unit had hysteresis at both ends, as any good design would. The unit I examined would cut off at 9.77 volts and would stay off until voltage rose to 10.994 volts. For overvoltage, the unit would trip off at 15.57 volts and start back up when voltage dropped below 15.000. Unlike another reviewer, I did not note any beeping sound from the unit when input voltage dropped too low. Note that common wisdom for lead-acid batteries and gel cells says not to take them below 11.6 volts/no load. I’m not sure how that translates to loaded voltage, but exercise caution if running this thing at full load for an extended time repeatedly from a battery that is not being charged.
I’m going to give this unit an A+, and I’m a hard grader. And $45.99? At that price point, you may not expect much: you’ll be pleasantly surprised with this Bestek unit. Worth every penny. And no, I’m not on the company’s payroll; just pleasantly surprised and impressed with this unit’s design excellence and manufacturing quality. That and I was a little bored today, thought I would take some measurements and share my insights. Can you tell? :)
Reviewed in the United States on March 15, 2021
Output voltage regulation is excellent; I tested it from 10 VDC in to 14.4 VDC, and it sags only a little, from 114 VAC RMS down to 110 VAC RMS. Your attached appliances will never know the difference.
Mine clocked in at 59.99 Hz from 14V in, 60.02 Hz at 10V in; again, your appliances will never know the frequency difference, as frequency regulation is excellent. I ran FFT on the sinusoidal output to check harmonics; the highest was the 4th at 40 dB down. The sinusoidal output is very pure, very clean.
Ever the curious one, I took a look inside. Four TO-220 nicely heat-sinked switching FETs (presumably) operating in tandem to drive a series toroidal inductor/capacitor low-pass (shaping) filter. The switching frequency is right at 25 kHz, and pulses range from 760 nS up to whatever width is required to maintain the waveform, depending on load and phase angle. I measured this on the driven side of the L/C output filter, see pics.
This unit does generate some hash in the AM radio band, no surprise. It might generate RF noise at higher frequencies including the HF bands (I didn’t test that; hey, this is a free product review), but if you’re a ham radio operator, you’re probably running off of batteries if you need low noise. It’s probably within FCC Part 15 unintentional radiator limits; I didn’t test conducted or radiated emissions either.
I bought this unit because my DJI drone battery chargers (3 different drones, 3 different chargers) refused to recognize my older “modified” sine inverters as providing useful AC power. I don’t blame them; whoever named it “modified sine wave” definitely worked in marketing, not engineering. And they’re rude. All of my DJI chargers work fine with this Bestek Sine unit, and why wouldn’t they? They’re being fed a swell, 60-Hz sine wave, just like at home.
I highly recommend this unit. It’s internally fused, so you’ll have to do some soldering if you pop the fuse. You need to remember that 300 watts at 120 VAC is only 2.5 amps, but at your 12V input, it’s 25 amps assuming 100% conversion efficiency. Assuming a realistic conversion efficiency north of 80%, that’s 30 amps.
Many automotive cigar lighters are fused at 10A. Never replace a 10A fuse with a 30A fuse to keep it from popping. There’s a reason auto manufacturers made that a 10A fuse, and it’s the wiring between your battery/charging system and the cigar outlet. Don’t turn your car into a crispy critter by upping any fuse, certainly not this one. If you need 300W, either make sure your car or truck cigar lighter fuse can handle the 30A, or buy some healthy alligator clips and attach this unit, via dual inline 30A fuses, directly to your battery. It’s also worth noting that most automotive alternators will produce about 50 amps at idle.
I plugged three 100W incandescent bulbs to my Bestek 300 W Sine Wave inverter and read 253 watts on my handy Kill A Watt P3 test instrument. I attached it to my 36 AH fishing-motor battery and ran it for several minutes with no discernible heating of the inverter casing or the air at its vents. I also attached my iPhone to the USB output, and the USB outputs on this unit are indeed wired to charge iPhones (proper resistor-divider values on the USB data pins). It measured 1.56A into my iPhone, probably current limited by the phone, for a nice fast charge.
The fan seems to have two speeds: modest and off. When operating, it’s fairly quiet. As you might expect, whether the fan runs or not is not so much affected by load; most of the power dissipated in switch FETS is related to moving charge and intermediate resistance value during transitions, not to Rdson losses. Assuming these are FETs (highly likely).
I tested low-voltage and overvoltage cutoff points, and found that the unit had hysteresis at both ends, as any good design would. The unit I examined would cut off at 9.77 volts and would stay off until voltage rose to 10.994 volts. For overvoltage, the unit would trip off at 15.57 volts and start back up when voltage dropped below 15.000. Unlike another reviewer, I did not note any beeping sound from the unit when input voltage dropped too low. Note that common wisdom for lead-acid batteries and gel cells says not to take them below 11.6 volts/no load. I’m not sure how that translates to loaded voltage, but exercise caution if running this thing at full load for an extended time repeatedly from a battery that is not being charged.
I’m going to give this unit an A+, and I’m a hard grader. And $45.99? At that price point, you may not expect much: you’ll be pleasantly surprised with this Bestek unit. Worth every penny. And no, I’m not on the company’s payroll; just pleasantly surprised and impressed with this unit’s design excellence and manufacturing quality. That and I was a little bored today, thought I would take some measurements and share my insights. Can you tell? :)
Top reviews from other countries
This charges my lap top super fast!
Doesn't make any weird electronic noises and doesn't get hot.
The "on/off" switch is just for the 12v plug ins. So the usb port charges the whole time the inverter is plugged into ur vehicle.
Reviewed in Canada on July 25, 2023
This charges my lap top super fast!
Doesn't make any weird electronic noises and doesn't get hot.
The "on/off" switch is just for the 12v plug ins. So the usb port charges the whole time the inverter is plugged into ur vehicle.
Keeping this in my vehicle as a backup when I need power conversion. Even though the instructions specify a 40 amp fuse is built in to prevent overheating/overloading, keep in mind how much wattage your 12 volt vehicle port can handle just in case. Too bad it does not have any clamps so that I can connect it directly to my battery.
Reviewed in Canada on July 6, 2023
Keeping this in my vehicle as a backup when I need power conversion. Even though the instructions specify a 40 amp fuse is built in to prevent overheating/overloading, keep in mind how much wattage your 12 volt vehicle port can handle just in case. Too bad it does not have any clamps so that I can connect it directly to my battery.