Bestek 300w Pure Sinewave invertor review

[barryd]

With nothing much better to do this morning while away in the van I thought I would review this little invertor from Bestek we bought before coming away on this trip.

Never really used invertors before believing them to be an inefficient use of power apart from an old one Don Madge gave me which was useful for charging old phones etc but I bought this one as Mrs D has a new laptop which I couldnt get a 12v adaptor for and also she knackered her electric tooth brush on the old invertor so as this one is pure sinewave it should have been safe for charging laptops, or other sensitive electrical items like tooth brushes, mobile phones etc.

This is it. https://www.amazon.co.uk/BESTEK-Pow...0CCJ9W9Z4D5&psc=1&refRID=63726TSK50CCJ9W9Z4D5

Cheap I thought for a Pure Sine wave.

Anyway we are on our fourth week away and Im pretty impressed. She has a fast charge 65w 240v charger which really charges the laptop up fast from low to fully charged in about an hour where it then gives about eight hours usage. This does use a fair bit of leisure battery power but here is the thing, charge it early on then there is loads of sun to top the battery back up again. It does cause the invertors fan to kick in which is a bit annoying but not that bad but it goes off once her laptop reaches 90%.

The two USB ports seem to be powerful as well and charge mobile phones much quicker than the cheapy cigar socket plug usb chargers you can buy for a couple of quid.

I think the main advantage when you are relying on solar is speed of charging stuff here and this is perhaps where the invertor wins. This time of year the leisure battery thinks its fully charged by 11am so you can fill your boots with stuff charging or running of 12v early on in the day and its soon tops it back up again.

Good bit of kit and it also means I never really need to worry about finding 12v chargers again although I still use mine on my Lenovo thinkpad.

 

[trevskoda]

Charge you phones and l tops of the van electrics, no requirement for inverter unless to run a 230v fridge, good to read your findings mind you.

 

[barryd]

Charge you phones and l tops of the van electrics, no requirement for inverter unless to run a 230v fridge, good to read your findings mind you.

The problem with Michelles new laptop is I could not find a suitable 12v charger for it. There were a few USB C type chargers and someone had a thread going about one on here but doing the maths they would take hours and hours to deliver a full charge. This one allows us to use the full 240v 65w original laptop charger so it whacks in a charge in no time. It also charges other stuff much faster than off the 12v but generally I would agree. 12v is better. She has a habit of sitting up the front of the van as well when using it where I have to use a long extension to the 12v socket in the back (two much hassle to fit a socket up there) so she always runs on its battery. I use my laptop up the back so its always plugged in to its dedicated Lenovo 12v charger and always fully charged.

What you also find if there is a long lead to the device with a 12v charger is there is voltage drop so I tend to work near the back of the van with short leads straight off the vans 12v sockets near the leisure battery. All the sockets, solar charger etc are all down the back but her ladyship likes to sit up front

 

[wildebus]

The problem with Michelles new laptop is I could not find a suitable 12v charger for it. There were a few USB C type chargers and someone had a thread going about one on here but doing the maths they would take hours and hours to deliver a full charge. This one allows us to use the full 240v 65w original laptop charger so it whacks in a charge in no time. It also charges other stuff much faster than off the 12v but generally I would agree. 12v is better. She has a habit of sitting up the front of the van as well when using it where I have to use a long extension to the 12v socket in the back (two much hassle to fit a socket up there) so she always runs on its battery. I use my laptop up the back so its always plugged in to its dedicated Lenovo 12v charger and always fully charged.

What you also find if there is a long lead to the device with a 12v charger is there is voltage drop so I tend to work near the back of the van with short leads straight off the vans 12v sockets near the leisure battery. All the sockets, solar charger etc are all down the back but her ladyship likes to sit up front

Having an Inverter means you don't have either the faff or expense of finding dedicated 12V versions of mains chargers for a Laptop. And then repeating the process when you change the laptop for a different model.
Much easier.

I have a little semi-Amazon branded 300W MSW inverter which is actually Bestek and I think it is very good. Use it to provide a constant discharge load for battery testing (plugging in standard 240V lights for the draw) and it is rock solid for hour after hour.

 

[barryd]

Having an Inverter means you don't have either the faff or expense of finding dedicated 12V versions of mains chargers for a Laptop. And then repeating the process when you change the laptop for a different model.
Much easier.

I have a little semi-Amazon branded 300W MSW inverter which is actually Bestek and I think it is very good. Use it to provide a constant discharge load for battery testing (plugging in standard 240V lights for the draw) and it is rock solid for hour after hour.

It was always my belief that they use more power and maybe they do but so far so good and the fast charging Is for us at least a benefit.

 

[Nabsim]

Very low overhead on the 300w Bestek in my opinion. Running 32” 230v tv through my modified sine wave came in around 2.5 amps.

 

[wildebus]

It was always my belief that they use more power and maybe they do but so far so good and the fast charging Is for us at least a benefit.

There is an overhead for sure.
And if you had a big inverter supplying a smallish load, the inefficiency is greater as there is a minimum amount of overhead - so if you had say a 2000W inverter for arguments sake and you turned it on to provide a low wattage, it would be more wasteful than using a 300W inverter for the same purpose.
(and if that inverter was already on anyway, the extra load of the charger has little extra waste over the power used as the overhead is already present, if that makes sense).

I was using my Laptop in the motorhome last couple of days and it was drawing just 24W, supplied by my 1300W inverter, but the fact I can just take my normal 'house' charger with me and plug in it compensates for the wasted power IFAIAC.

 

[jagmanx]

Looks a good choice.
For me powering the inverter off a standard 12v socket suits.
300 watt divided by 12(v) means a 12v draw of 25 amps or am I neing stupid. Time is not the problem just cable size ?
As posted provided you use during the day the battery bank will be topped up. I would be worried about fuse and melting wiring and so would prefer it hard wired to the battery bank with a dedicated switch and fuse.

 

[wildebus]

Looks a good choice.
For me powering the inverter off a standard 12v socket suits.
300 watt divided by 12(v) means a 12v draw of 25 amps or am I neing stupid. Time is not the problem just cable size ?
As posted provided you use during the day the battery bank will be topped up. I would be worried about fuse and melting wiring and so would prefer it hard wired to the battery bank with a dedicated switch and fuse.

I can't recall if it is the case with the Bestek, but quite a few of the good smaller inverters come with both 12V Plug cables and hard-wired connection - and self-limit the power when the Plug is used for protection for the reasons you say.
300W on a 12V socket would likely blow the supply fuse to the socket as they are often rated at 120W and fused at 10/15A

I am intrigued now and think I might compare the load of my Victron Multiplus 12/1600 (1300W) inverter compared to the little 300W Amazon/Bestek when all I want for 240V is Laptop power

 

[jagmanx]

Speak on Tueday !
I do not need/want an inverter but !?

 

[Tezza33]

I also have a Bestek 300W pure sinewave inverter, it is very useful and I have never had a problem with my 12V socket

 

[Stanski]

..... 300 watt divided by 12(v) means a 12v draw of 25 amps or am I neing stupid. ....

Morning everyone. An interesting discussion as this has been frequently on the forum in previous years.
Can I throw a cautionary tale in the mix - just recently my Unc had a problem with running his 750W microwave using a 1500/3000Watt max inverter after he had changed his leisure batteries from 1 large coach style to 2 medium 110A types and fitted a second solar panel for extra charging.
Cautionary Tale of the Unexpected If you own an Inverter
Soon after the fit modification he found things did not work correctly and from advice he changed to larger cables joining the batteries and repositioned the connectors to the inverter - seemed to work OK until 2 weekends ago when he experienced the inverter warning alarm every time he tried to use the microwave.

A planned visit was used to investigate and what I discovered was a little alarming (Not a pun).

WARNINGS
- Ensure inverter is disconnected from all sources and not connected to any external items
Advice - On this inverter a capacitor holds a charge on the alarm circuit so even after disconnection switch the output on - this will sound an alarm for few seconds until the capacitor discharges fully - you may also see a green LED show on for a few seconds.
Initial Investigation -
Internally the inverter was pristine which after 4.5 years use was good to see - except for one component "The input Fuses"
The circuit had been designed to use 3x 30amp spade fuses on both the negative and positive supply feeds (6 in total).
These basic car fuses had plastic coverings that had melted severly, as well as the metal spades also slightly corroding causing a failure in the physical connection.
Probable Cause
The input current flow had been high/excessive in my judgement, thus generated high heat to melt the plastic fuse covers in a way that caused the metal of both the fuse and its terminal to distort.

The inverter could not "Pull" enough current to function so went into an alarm state.

Repair was achieved by replacing the fuses with new and so far the inverter behaves correctly - time will tell.

Conclusion - using high wattage equipment on inverters for long periods may cause you problems such as described above.
An annual check of the inverter might be worthwhile - if you feel capable of doing it it would take about 30minutes to remove the upper cover inspect and replace cover.

hope the story helps someone

 

[trevskoda]

Thats why many folk use gas for a oven and plates.

 

[barryd]

Looks a good choice.
For me powering the inverter off a standard 12v socket suits.
300 watt divided by 12(v) means a 12v draw of 25 amps or am I neing stupid. Time is not the problem just cable size ?
As posted provided you use during the day the battery bank will be topped up. I would be worried about fuse and melting wiring and so would prefer it hard wired to the battery bank with a dedicated switch and fuse.

I think for us it's fine off the Kontikis original Hab 12v socket. The maximum draw will be a laptop charger at 65 watts. So far so good and the inverter itself doesn't get warm. I did read on the reviews that if you plug it into a low power car cig socket it will sense that and limit it's supply to about 100 watts. Still more than enough for me.

Interestingly I plugged my laptop into the load socket on my mppt controller today using its dedicated 12V charger just the see what it draws and it was between 18-20 watts while already fully charged and watching Iplayer. It went up a few watts when I plugged my phone into a usb port.

I guess I could plug the inverter into this load socket and then power Michelles laptop to see how much it draws. The only worry is I fitted it so it might blow up