PV Gap

Tara Said:

Can anyone recommend a inverter they currently use in their home for solar?

We Answered:

if you are going to attempt to run a 4 ton a/c unit on batteries you might wish to rethink this whole solar scheme .a few facts :a 4 ton unit will draw a constant 36 amps (give or take 8.75 amps )depending upon the ambient temp (4500 watts @125 volts )and half of that for 250 volts ,thats your running current then there is the starting surge which can go as high as 12 times the running load (54000 watts at 125 volts) this kind of a surge will kill most inverters ,and as the temp outside climbs the running current will rise higher as well.look for the "locked rotor current on your unit and also the code letter ,the code letter in a grouping of units that operate at a certain locked rotor current and the higher this value is the more it will cost to get an inverter that will put up with that kind of starting amps ,secondly in order to run that size of load you world need a capacity of 33000amp/hours at 12.5 volts d.c.as the inverter will draw 333 amps per hour to run this a/c unit at 4500 watts ,so then your battery banks will have to consist of twenty six group "8-D" batteries per bank for an 8 hour rate and at 200 bucks a pop this will get quite spendy as you will require at the very least six and possibly eight banks ,this is roughly $1,200 just for batteries and then comes the solar collector panels ,the most powerful ones I have seen come in at about 225 watts each which meand you would need at the least 1834 such panels at a cost of nearly &1,182,499.90per bank of batteries ,now you are thinking "how can I do this for less >get a solar driven absorption type air conditioner ,it will be cheaper i the short haul and in the long run as well as for the rest of the appliances in this house learn to get by on the bare minimum number of current intensive units that you possibly can ,although solar power IS green It still takes a lot of green to get there running an electric 4 ton a/c unit on total solar is at best expensive if not altogether foolish ,find other ways to cool your abode with the sun

Carrie Said:

I have a Usha Zentra home inverter and my original battery has given me good service, time to replace battery?

We Answered:

That's 750 - 800 watts, of course...

I'd say, if the old battery gave good service, get the same kind again. I'm not sure what is meant when a battery is advertised as "solar" - maybe that just means deep cycle.