inverter sizing

BFL13 wrote:
There is little difference if any between 1000w inverter and a 400w inverter for draw while running TVs etc. (you do see a diff if you do it with a 2000w though)

It is all about inverter efficiency curves which are best at say 3/4 the wattage. So if your load is going to be 150w you want a 200w inverter. But if you use a 1000w inverter it's nearly the same AH out of the batteries.

The difference is the wiring and fusing for the inverter based on what the inverter could do. But you can wire it up only for what you will do with it, so if you are certain of the max load, then you could use the same wiring for the 1000 as for the 400.

I only needed a 400, but some 1000s came up on sale and I grabbed one. I only use it as though it were a 300, but I do have a nice back-up for the 2000w for running up to 100a loads like the kettle or toaster. Still need the 2000 as it is the only one that will run the microwave.

So the lesson is, you don't lose any AH by running the 1000w instead of a 400w for the TV/DVD but you gain some redundancy for running the kettle and toaster.

I whole heartedly agree with BFL. I went what I thought was "overboard" got a good deal on a 1000W Xantrex PSW inverter for TV etc. Pretty soon DW said "will it run the hairdryer" one of those travel ones. Yup, but a 400W wouldn't. How about the toaster?? Yup.

And finally after her commenting that the micowave would be nice at lunchstops at rest areas, I put in a $100 panasonic "inverter" microwave that will run just fine on 1000W if you set the power level to 50%. And at 50% power, it only adds about 25% or so to the time it takes to warm stuff up. And we can run the microwave when dry camped without going out and firing up the generator.

so, after two years, the 1000W isn't "overboard" it's "adequate" and had I done a 400 or 600 W I'd have decided it was "almost adquate" not to be confused with "barely adequate".

BTW I've been very happy with the Xantrex.