Dirty generator power

[Rufus2502]

I live off grid, and use a generator to top up my battery bank in the winter when my solar is not producing, my inverter generator died, and I don't have the money to replace it, I'm using a back up Chinese nasty capacitor run geny, I would like to know if there is any device I can buy to safely use cheap generators with dirty sine wave outputs with my digital battery charger that will protect it from being fried ?

 

[Pete999]

Voltage Stabilizer

 

[HandySparks]

Small inverter generators are pretty cheap nowadays if you don't care about the make. I expect that a device that will properly protect your charger is likely to cost as much:

Clarke IG950 800W Inverter Generator - Machine Mart - Machine Mart - https://www.machinemart.co.uk/p/clarke-ig950-800w-inverter-generator/

 

[Deleted member 105166]

I'm using a back up Chinese nasty capacitor run geny, I would like to know if there is any device I can buy to safely use cheap generators with dirty sine wave outputs with my digital battery charger that will protect it from being fried ?

Is your set diesel or petrol? (Forget about small petrol sets for anything other than perhaps site lighting or a power tool.)
As Pete suggested, you could fit an AVR module, however if the output is really erratic, that probably won't last too long.
You can pick up a 6kVa diesel set secondhand for not a lot and it will give a stable output. Look for a secondhand Stephill and put a new capacitor in it and you'll be good for a long time.

 

[dmxtothemax]

The trick with generators is to have a stable load,
The reason generator voltage fluctuates,
is because the loads are fluctuating.
Use a stable load of at least 50% of the generators capacity.
this will keep the output stable.

 

[Lucien Nunes]

It depends what you mean by dirty. Capacitor-excited generators tend to produce a distorted waveform especially with extreme load pf. But that isn't necessarily harmful and is unlikely to damage your charger. Most likely, the charger is based on a straightforward switched-mode power supply that rectifies the incoming mains, in which case the genny output can be as nasty as anything without causing harm or affecting the performance of the charger. Old ferroresonant chargers were touchy about waveform annd frequency but you describe it as digital.

If by dirty you mean unstable, and self-regulating generators without electronic AVR can be a bit wide on their voltage tolerance, then as Pete says you could post-regulate with a voltage stabiliser. You can't do much about the frequency regulation, and some cheap portables are rather poorly governed, but again, if the charger is SMPS based it's probably OK up to 254V and will accept a wide range of frequencies. So as long as you don't add lots of capacitive load that makes the genny over-excite, or set the governor too far off the mark, it's probably OK.