MPPT Charge controllers and Panel Connections

[Sunking]

What do you mean may never recover from?

Maybe you have more money than you know what to do with, but if it were me I would go broke buying batteries every year or two. Especially a $30,000 set. That is where you are heading.

[jflorey2]

Thanks for the info. Can you explain why this battery sizing causes problems for my install.

You will damage your batteries by overcharging them. You have 72kwhr of batteries; they can accept at most 9kw charging power. You can accomplish this by limiting output current of your charge controller - but that leaves you with unused solar capability.

[Wy_White_Wolf]

Thanks for the info.
Can you explain why this battery sizing causes problems for my install. By my calculations 1200ah is more than enough for my requirements. I have upsized the panel capacity to cope with bad weather etc.
2x 8kva inverters are to cope with short high load requirements only.

310 amps into a 1500Ah battery bank puts you at about a C/5 charge rate. That'll destroy FLA batteries by being to high. AGMs can handle that high of a charge rate occasionally but doing it every day will also destroy them.

So how did you calculate the 1200Ah? Is that what you calculated you need? How did you calculate for the 1500Ah battery bank?

If your daily need is 1200Ah you need a 6000Ah battery bank as you should not use more than 20% of it daily. That also gives you 2.5 days autonomy before reaching the 50% limit that you should avoid going below.

WWW