Batteries

"20 amp hour rate 215
5 amp hour rate 157
6 amp hour rate 156"

It's the 20 Hour rating is 215 amp hrs
Means it can supply 10 amps for 20hrs 45 mins
To reach 10.5v

The 5 hrs rate is 157 amp hrs
That is discharging at a rate roughly 30 amps load
3x the load for 1/4 the time period and less total capacity

2oldman wrote:

wolfe10 wrote:
Both pairs together (your battery bank) is 550 AH @ 12 VDC.

-100

Some incorrect math in this thread.
-120
For a total of 430 AH @ 12VDC :B

wolfe10 wrote:
Both pairs together (your battery bank) is 550 AH @ 12 VDC.

-100

Duracell 225?

Try 208

Trojan T-105 are 220

The most commonly used rating is the 20 amp hour rating

"The amount of amp-hours (AH) a battery can deliver when discharged at a constant rate at 80°F (27°C) and maintain a voltage above 1.75 V/cell."

1.75 V/cell is past the typical amount you would discharge a battery to and, if done repeatedly, will shorten the life of the battery. For maximum life, do not discharge past 80% "state of charge" (SOC) which is 2.08V/cell. (12.48V for a 12V battery bank.)

Minutes at 25 amps (also referred to as Reserve Capacity) is another good reference, but not all manufactures publish this.

Yours are 215 amp-hours, typical for most 6V golf cart batteries. If they are wired 2 in series and then 2 in parallel, you have 430 amp hour @ 12V.

ON EDIT: Thanks to all who posted below who corrected my "BAD MATH". Concept correct, math not so much. Rather than leave questions, I will edit to supply, as others have done the correct answer: 430 AH @ 12 VDC.



The 20 hour rate is the most common rating.

So, each of your batteries is 215 AH @ 6 VDC. So each pair wired in SERIES is 215 AH @ 12 VDC.

Both pairs together (your battery bank) is 430 AH @ 12 VDC.