Generator

[JohnW2]

Since any switch mode power supply or inverter drive turns all power to DC then back to AC there should not be a problem with simulated sine wave with any units using that technology.

Come on, Eric - you know that's simply untrue. Many cheap inverters put out something which barely resembles a sine wave. And therein lies the problem.

I have to say that my inclination is to largely agree with eric on this one. You are right that "many cheap inverters put out something which barely resembles a sine wave", but I would have thought that, as eric suggested, this would not be much of a problem with most SMPSs. I would have thought that they would probably usually work (at least, after a fashion) with a DC input or a square-wave AC input, or anything in between.

Kind Regards, John

 

[ban-all-sheds]

Ah - I think I misread what he said - I thought he was saying that because inverters turn DC into AC then they are bound to put out a good sine wave.

 

[JohnW2]

Ah - I think I misread what he said - I thought he was saying that because inverters turn DC into AC then they are bound to put out a good sine wave.

Ah, again! No, as I implied, I think he was saying that since the first thing an SMPS (as in TV, computer, phone charger, ELV lighting etc. etc. etc.) does is turn the input voltage into DC, the waveform of that input supply shouldn't really make any difference to it. If the output of the SMPS is AC, then it's output waveform will be as bad as it always has been - but the load (lighting or whatever) would presumably be used to that! ... i.e. he was not talking about the inverter of an inverter generator but, rather, SMPSs supplying end-loads.

Kind Regards, John

 

[ban-all-sheds]

Looks that way.

 

[a546345]

I have a 2 year old Samsung inverter fridge freezer, and it ran fine on both the 2.2kVA site generator and the 2kVA inverter generator. The normal compressor chest freezer, and separate freezer we had before the Samsung also worked fine on both gens. The gen would also have been powering another 0.5kW of load at the time (ch, tv, lighting, PCs etc.)

I do find though that during power cuts, we immediately have the urge to eat and drink, which means the fridge gets opened more than normal!

Before I got a generator, I used to run a 150W modified sine wave inverter from the car, and plug the boiler in to it for an hour or so to give a bit of heat. The CH takes about 80W.

Do you get regular power cuts BAS? Or is this for "just in case"?

 

[ban-all-sheds]

The latter. I fear the former will become more common.

 

[oldbutnotdead]

If its just occasional, the machine mart invertor gennie seems OK. Don't try and run a MIG welder off it but it does handle my little compressor (B & Q thing, about 600W but more on startup) and the microwave and the laptop, phone charger etc. I've never looked at the waveform but I think it is probably fairly shoddy- it runs florrie tubes OK but the fan on the caravan central heating doesn't run at full speed properly without a nice fat resistive load on the gennie (eg tyre warmer @ 500w or a sunflood with a real tube in it).

Used to have a Kipor 3kw inverter gennie- that would run the MIG. Shame some git nicked it.....