Schneider System Issues

Telecom batteries were designed for high surge and few ( less than 50 cycles) so I would expect them to fail soon in a demanding RE application

96 Degrees in the shade wrote: »

Thanks for the heads up, I am saving for some batteries

It has been mentioned by Dave Angelini that 400ah is the minimum. I don't know if they ever changed the manual, but it used to read just 100ah for the XW6048, which confused many, many people, so obviously 400ah is much better.

But the key to the battery size is the array size. I have a 4.7kw array, and was able to get away with 357ah batteries by partially throttling the output down with the charge controllers on occasion.

Solar Guppy, a PV expert, advised people to get 100ah / kw of array size. So for a 6kw array for 96 Degrees in the shade, it would indicate about 600ah @ 48V for the battery bank. I'm thinking that even 400ah might be a bit too small, as that is just 2/3 the size recommended by Solar Guppy. Mine was about 76% of his recommended 470ah, and I still had to be extremely watchful. I was told part of the problem with an undersized battery bank was the ripple current that would hurt smaller batteries, but it might as well be quantum mechanics for how much I can understand it.

BB. wrote: »

More or less, a good starting rule of thumb (from Solar Guppy) is minimum of 100 AH @ 48 volt per 1 kWatt of inverter power (lead acid batteries).

And a maximum of 1 kWatt per 100 AH @ 48 Volt battery bank solar array sizing for lead acid batteries.

You can go into details and discuss when/why/how to vary those numbers.

-Bill

And it should be mentioned we are talking about the 20 hour rate at 400 AH. The Schneider XW6848 states this as all of the XW manuals have since Mr. Guppy tried to use the system with a smaller battery close to 10 years ago.