I'll withdraw my other comment about not feeding back to the grid.

I do apologise. From the Xantrex blurb, it appears this unit does indeed feed back to the grid.

Grid-interactivity allows excess energy that is generated to be exported to the grid, and allows the grid to act as an additional energy source to charge the system's batteries.

Do your sums and look at the options and I'm sure we'd all love to hear about your experience!

Thanks for the information, it's certainly been enlightening for me

Ian

--- In SunGrid@yahoogroups.com, "Ian Ritchie" <scantec1@...> wrote:
>
> Sorry, I misinterpreted your requirements.
>
> If you have no desire to feed back into the grid, then there are many inverters that can do it, in fact a simple double pole changeover switch is all that is required.
>
> The Xantrex unit you showed, does not feed back to the grid, but it does power share (parallel) with the grid, so as reducing your grid consumption. They usually also have a power boost function, which is handy at times when the grid supply is limited (boats and RVs for example) which actually boosts the grid power for short durations by using battery power. There are a number of inverters on the market with these features (Mastervolt also has one). Remember, the quiescent current increases with all these "dinky" add-ons which usually are not necessary. Good design beats sparkles and glitter :-))
>
> Depending on where you live, you may also find the supply authority company may not let you use these inverters without registration with them first (which may also require testing and approval applications at a cost).
>
> Ian
>
> --- In SunGrid@yahoogroups.com, Iftikhar Khan iftikhar21@ wrote:
> >
> > Actually what I was looking for I found by accident. Xantrex makes this
> > inverter, more details here.
> > Please see figure 2, grid-tie system with backup power
> >
> > http://www.xantrex.com/web/id/25/learn.asp
> >
> > Just thought to share it with you guys.
> >
> > <http://www.xantrex.com/web/id/25/learn.asp>
> >
> > On Thu, Oct 15, 2009 at 2:30 AM, Ian Ritchie scantec1@ wrote:
> >
> > >
> > >
> > > You're asking about two (usually) different items. The common grid tie
> > > inverters aren't usually configured to 12Vdc (or 24Vdc).
> > >
> > > My best guess is your essential loads are fairly minor (assuming you aren't
> > > referring to refigeration), so a stand alone cheap inverter would be
> > > preferable unless you wish to go the way already suggested of a dc essential
> > > circuit.
> > >
> > > Also, since you are connected to the grid mostly, why use solar to charge
> > > the batteries, when you could charge them effectively from a night rate
> > > tarrif, whilst using all the solar to feed back at either the day tarrif or
> > > better still, a higher feed-in tariff.
> > >
> > > Food for thought!
> > >
> > > Ian
> > >
> > >
> > > --- In SunGrid@yahoogroups.com <SunGrid%40yahoogroups.com>, "iftikhar2121"
> > > <iftikhar21@> wrote:
> > > >
> > > > I've been looking at various big name brands and wasn't able to find what
> > > I'm looking for, so I decided to ask you guys, if you can tell me, if what
> > > I'm looking for exists and makes sense.
> > > >
> > > > I'm looking for an inverter, that's a "hybrid inverter", so it can take
> > > power from the grid, like a grid-tied inverter, and also work as an off-grid
> > > inverter. So basically it would be an inverter that can connect my PV array
> > > to my load, and also to the grid.
> > > >
> > > > If for some reason I don't have power from the grid for a few hours, I
> > > can still run my critical load, from the power stored in batteries (battery
> > > bank).
> > > >
> > > > Most inverters that I looked at, are only grid-tied, (can not connect to
> > > batteries), or off-grid (can not connect to grid), That's why I said, I need
> > > a "hybrid inverter". That can do both jobs with one machine.
> > > >
> > > > Thank you and I'll be very grateful for any help and guidance.
> > > >
> > >
> > >
> > >
> >
>