k1vsk...that's a fairly normal house bank with all parallelled. Mine is 1000+ with 4x8d's.
group 27's are generally around 90-100ah's each and 110 is actually quite high. I would simply use 90-100 ah's as my amount per battery IF they are new. It doesn't hurt to err a bit on the low side as extended battery life will be the result of charging before you reach 50% discharge.
SOLARE...you are correct...do NOT do what Xantrex suggests. If you are not content with estimates then you can do the following.
1. EQ the batteries.
2. Fully charge the batteries.
3. You have approximately 400ah capacity at the 20 hour rate which means that at a 20 amp load you should get 20 hours before you reach 10.5 volts. 4. Get a 20 amp test load and run the batteries down to 12.2V. (50%). They SHOULD last 10 hours before reaching 12.2V. If they only last 8 hours...you have 80% of rated capacity...5 hours is 50% etc.
5. Again...if the batteries are new...no need to go through this.
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