240v vs 120v,,,

[Dexter]

Hello - question for you experts.  Is it better to connect my generator to my inverter using 240v or 120v?  I can do either.  It might just be my imagination, but I get much better charging performance when I'm plugged into 120v house supply versus 240v generator supply.

For one, the inverter seems to perk right up.  When using 120v, the internal fan comes on and it seems like it's working more.  The fan never seems to come on with 240v.

Is that because there is lower current with the 240v?

How do all of you do it?  Which is best?

thanks!

[Flux]

It is fairly normal for small generators to perform badly compared with mains supplies with most battery chargers. It is due to the comparatively high source impedance of a generator compared with a stiff grid.

When using the generator choose whichever voltage gives best results ( probably 240)

Flux

[Off grid in Tonopah]

Putting the load of the charger on the generator at 220V is better for the generator and keeps the load balanced. This would be especially beneficial for a small gas gen set. If you still want to use 110V input to the inverter Outback makes a load balancing transformer that works great. I have one installed in my system on the generator output just for load balancing but it will do 220v to 110v or back the other way. All and all a real cool and versatile little piece of equipment.

                                                 Bob

[Nando]

240 is the preferred voltage because the efficiencies are better and the generator is load balanced.

If you need to have 120 volts, as well, then a balancing transformer to transfer power from one side of the 120 to the other side of 120, Xantrex sells a transformer but it is expensive.

A cheaper version is to get an auto transformer 230/115, open it and get the three leads,

220. line,
     
115. line and
     
     

(neutral),

take the center lead = 115 volts and connect it to neutral of the load wiring,

then the 230 line goes to one 115 volts

and the (neutral) of the transformer goes to the opposite 115 volts,

Make sure that the (neutral) of the transformer is not connected to the body of the transformer, if it does you need to separate the connection.

The same size KW auto transformer than the Xantrex will cost much less than half their price.

Nando