Samlex Solar SCC-30AB Owner's Manual page 12

3
GENERAL INFORMATION: BATTERIEs
then recharged. If an SLI battery is used for this type of deep discharge application,
its useful service life will be drastically reduced.
This type of battery is not recommended for the storage of energy for DC powered
devices like lighting, radios, inverters, etc. However, they are recommended as
starting battery for the back-up generator.
Deep Cycle Lead Acid Batteries
Deep cycle batteries are designed with thick-plate electrodes to serve as primary
power sources, to have a constant discharge rate, to have the capability to be
deeply discharged up to 80% capacity and to repeatedly accept recharging. They are
marketed for use in recreation vehicles (RV), boats and electric golf carts – so they may
be referred to as RV batteries, marine batteries or golf cart batteries.
Units of Battery Capacity – Ampere Hours (Ah) and Reserve Minutes (RC)
Battery capacity is the measure of electrical energy the battery can store and deliver
to a load. It is determined by the amount of current any given battery can deliver
over a stipulated period of time. The energy rating is expressed in Ampere Hours (Ah).
Normally, Ah capacity is rated at 20 Hour discharge rate i.e., the number of Amperes of
current the battery can deliver for 20 Hours at 80ºF (26.7ºC) till the voltage drops to 10.5V
for 12V battery and 21V for 24V battery. For example, a 100 Ah battery will deliver 5
Amperes for 20 Hours.
Battery capacity is also expressed as Reserve Capacity (RC) in minutes. Reserve capacity
is the time in minutes for which the battery can deliver 25 Amperes at 80ºF (26.7ºC)
till the voltage drops to 10.5V for 12V battery and 21V for 24V battery. Approximate
relationship between the two units is as follows:
Capacity in Ah = Reserve Capacity in RC minutes x 0.6
Typical Battery Sizes
The Table below shows details of some popular battery sizes:
BCI* GROUP
27 / 31
4 D
8D
GC2**
* Battery Council International
12
BATTERy VOLTAGE, V
12
12
12
6
** Golf Cart
Table 3.1. Popular Battery Sizes
BATTERy CAPACITy, Ah
105
160
225
220