5KVA Pure Sine Wave Inverter Generator

[gavinwibrow]

Has anyone bought one of these iTech Redback generators? WA company that has been around for a while and with some good looking camping and backup options.

Listed at $2,300 but regularly advertised at $1,899 - even on their site. Redback RB4 5KVA Pure Sine Wave Inverter Generator | Remote Start | LC | iTechworld (https://itechworld.com.au/products/redback)

Would love any feedback

[Toxic_Avenger]

Camping... maybe if you want something small quiet, and somewhat portable.
Backup ... well 4000W AC ain't gonna get you far.
There comes a time when it's folly to have a big engine driving a small alternator then inverting it up to 240V, when you could have a 240V alternator doing the same work for you without the losses of the inverter/rectifier.

But yeah... there are some experts here that will give you proper advice.

[Homestar]

Machines like this exist because the engines have quite bad load acceptance so using them as an inverter works quite well but there are decent loses involved. That's not a bad thing as you keep a nice clean waveform, and by running the engines slower in 'eco' mode allow lower noise output.

As for the unit listed, no help sorry - it's just one of the hundreds of Chinese units flooding the market. Most work fine for intermitant use but from what I've experienced the engines get hard to start after a few years, but maybe some of the newer stuff is better.

Check to see if parts are available for it - most Chinese units have zero spares available.

There's a reason we only use Honda Inverters at work - have several hundred of varing sizes. Yes, they are expensive but we have units with 1000's of hours on them with no issues. When they get damaged and on the odd occasion one does stop, parts are easy to get hold of.

Just my 2 cents - chances are the one shown would provide good service for a few years. Would I personally buy one if I was in the market? No, I'd save my money buy a Honda.

[Toxic_Avenger]

Why buy Honda, when you could buy CHonda... Twice [thumbsupbig][bigwhistle]

[gavinwibrow]

Camping... maybe if you want something small quiet, and somewhat portable.
Backup ... well 4000W AC ain't gonna get you far.
There comes a time when it's folly to have a big engine driving a small alternator then inverting it up to 240V, when you could have a 240V alternator doing the same work for you without the losses of the inverter/rectifier.

But yeah... there are some experts here that will give you proper advice.


Should have clarified, its camping I'm interested in, so yes 5KVA is plenty, and the weight and noise are within acceptable levels, at least for free camping.

[dirvine]

Interesting it says its 5KVA then later only 4KVA with a continuous load of 3.6! I looked at generators in detail for my caravan and the specs mentioned for this unit just seem too good to be true. Noise quoted must be at idle not under load, and it needs 95+ RON fuel! I ended up with a Cromtec Outback which is 2.6 nominal and 2kw continuous. This has good back up support around Aus (not as good as Yamaha and Honda) but is about 1/2 the price of them. I viewed that using it for about 2 months max a year, when off the grid and needed 240V, the cost of the well known brands was just too much

[trout1105]

I bought a generic brand 2.4kva inverter genset a couple of years ago for about $700 and it hasn't missed a beat so far, It can run an air conditioner or even an electric kettle.
It weighs 28kg and will run for 10-12hrs on 5l of petrol more if it is only running a fridge or freezer on economy mode.
I am toying with getting a 5kva unit But at the moment the 2.4kva is doing the job.

[Toxic_Avenger]

Interesting it says its 5KVA then later only 4KVA with a continuous load of 3.6!

I've sold the occasional genny at work (not well, admittedly!), but there is a bit of confusion with watts and kVA.

If you have a 5000W genset, the kVa rating is the wattage multiplied by the power factor (the OP's example has power factor of 0.8)
So 5000x0.8 = 4000 = 4kVa.
Then on top of that, there is probably some limiting factor at which the generator can maintain that load, to give you a continuous rating.


I work / supply to industrial customers, mainly the welding and fabrication trades. The weapon for choice for these guys is a Honda petrol motor driving a 240V alternator, with a minimum of 9kVa for welding applications for a small 'inverter' style MIG or similar. To an extent, it's a folly using petrol to create a 12V output via the alternator, then invert it up to a 240V output. Trade level generators are all 240V single or 3 phase alternators paired to a suitable engine.

When you start talking larger welders and high amperage draw applications (air-arc gouging for example), you can't go past something like a Lincoln Air Vantage engine drive... good for simultaneous welding, generator and air compressor output. It's a workshop on wheels... but with a $65K price tag.

[Dorian]

Camping...
There comes a time when it's folly to have a big engine driving a small alternator then inverting it up to 240V, when you could have a 240V alternator doing the same work for you without the losses of the inverter/rectifier.
........

"without the losses of the inverter/rectifier" while absolutely true 10 years ago, not so much now. Still losses but no where near as much. I can see this in industrial inverter drives, heat sinks are now way smaller and you can put more drives in the same space because they generate so much less heat.

They probably use an alternator and generate at + 300 VAC + , then rectify it to 300 ish DC and then finally convert it to 240 VAC. The reason for this is that you wouldn't have to worry about the the frequency or the wave quality of the Alternator, this is handled at the inverter end. The 12V DC would be generated with a switched mode power supply. I'm pretty sure all of the brands use a similar method.

With all of the solar inverters on houses these days this tech has come down massively in price. Can't comment on the motor but all of the electronics would be similar as there are only a few source factories for the base components. The difference though may be the manufacturing quality of the circuit boards.


....... Noise quoted must be at idle not under load, ......

It quotes noise under load and at idle " producing only 56dB on full load and 49dB with no load at seven metres. " however it is at 7 meters and may or may not be to good to be true.

I'd think that 5KVA peak would be more than enough to bring in a domestic fridge and freezer and maybe a few lights, although probably not a water pump on top of that.

No experience with this brand but it's got an 18 Mth warranty and from what I see so many of our major brands have Chinese stuff in them anyway.

Cheers Glen.

[gavinwibrow]

So, what would be ideal, is a reasonably priced, lightweight diesel pure sine wave able to run a caravan a/c ie about 4K watts startup/5KVA. Then I can have one fuel source for cars and genset.

Then again, according to the pundits, aren't we supposed to be phasing out diesel, especially for urban? Not so much of a problem in the great outback, providing the fuel price doesn't go through the roof.

[goingbush]

I was looking for a 240V 15A / 3 phase generator to carry in the back of my Electric LandRover which would be required to pump out 3.3 kw for 6-8 hours , One that is quiet and also be able to lift it into the back on my LandRover unaided.

That would be 100km for approx 6 litres of diesel . Even with all the efficiency losses seems more efficient than running the vehicle on diesel, that would be more like 12L/100k instead of 6L/100k. my head hurts again.

I bought a Tandem trailer with my generator money instead.

[Homestar]

So, what would be ideal, is a reasonably priced, lightweight diesel pure sine wave able to run a caravan a/c ie about 4K watts startup/5KVA. Then I can have one fuel source for cars and genset.

Then again, according to the pundits, aren't we supposed to be phasing out diesel, especially for urban? Not so much of a problem in the great outback, providing the fuel price doesn't go through the roof.

Well there is a product that meets 1 out of your 3 wishes - you can buy a pure sinewave diesel 6KVA genset, but it aint light nor cheap...😁

[Homestar]

If you have a 5000W genset, the kVa rating is the wattage multiplied by the power factor (the OP's example has power factor of 0.8)
So 5000x0.8 = 4000 = 4kVa.
Then on top of that, there is probably some limiting factor at which the generator can maintain that load, to give you a continuous rating.

Tis other way around mate - 4000W is 5KVA - KW/PF.

Also worth noting that most single phase loads are close to unity as far as PF goes. Exception would be the AC units in vans but these sit around 0.9 so for calculating most loads it's better just to use watts. If it says 3,600 watts continuous, I'd just assume that as far as what it can run.



When you start talking larger welders and high amperage draw applications (air-arc gouging for example), you can't go past something like a Lincoln Air Vantage engine drive... good for simultaneous welding, generator and air compressor output. It's a workshop on wheels... but with a $65K price tag.

Got several at work - awesome units. 👍

[Toxic_Avenger]

Got several at work - awesome units. 👍

/me makes the Tim the Tool man Taylor grunt

https://www.aulro.com/afvb/images/imported/2018/04/436.jpg