2 batttery system...

Brian_L

Sorry. Dumb question In think.  Can1 have 1 12v battery with a 1000 watt inverter, run a conventional AC battery charger to charge a second 12v battery, ( also can I use charger in fast charge or boost?). Thanks in advance. 

BB.

Yes you can... The AC battery charger needs to be less wattage than the inverter rating. However, the battery charger design can be an issue too...

There are "modern" chargers that are full electronic that are pretty efficient, and there are older transformer type that can be pretty inefficient (power factor issue, and such). I would suggest that as a starting point, that the charger be 1/2 the rating of inverter (or less). for example:

• 1,000 Watts * 1/2 = 500 Watts (or VA--Volt*Amps)
• 500 VA / 15 VDC battery charging voltage = 33.3 Amps maximum suggested battery charger output--Or smaller

More or less, a good charging current would be around 10-20% of the battery capacity. For example, a typical "car battery" is around 80 Amp*Hour:

• 10% battery rate of charge * 80 AH = 8 Amp battery charger.

A "loo large" battery charger can be "hard" on Lead Acid batteries and wear them out faster (overheating of battery). 

-Bill