Samlex America SCC-30AB - Manuel (Page 14)

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GENERAL INFORMATION: BATTERIEs
PERCENTAGE OF
FULL CHARGE
STANDING VOLTAGE OF
12V NOMINAL BATTERy
Cell Voltage (12V BATTERy
HAS 6 CELLS IN SERIES)
100% 12.63V 2.105V
90% 12.6V 2.10V
80% 12.5V 2.08V
70% 12.3V 2.05V
60% 12.2V 2.03V
50% 12.1V 2.02V
40% 12.0V 2.00V
30% 11.8V 1.97V
20% 11.7V 1.95V
10% 11.6V 1.93V
0% = / < 11.6V = / < 1.93V
Table 3.3. State of Charge versus Standing Voltage – 12V Battery
Check the individual cell Voltages. If the inter cell Voltage difference is more than a
0.2V, the battery will have to be equalized. Please note that only the non-sealed /
vented / flooded / wet cell batteries are equalized. Do not equalize sealed / VRLA type
of AGM or Gel Cell Batteries (unless allowed by the manufacturer).
Battery Efficiency
A lead-acid battery has an efficiency of only 75% - 85%. The energy lost appears as
heat and warms the battery. This means that the Ampere Hour (Ah) energy required
to charge a battery to its full rated capacity will be approximately 120% to 130%
higher than the Ah capacity rating of the battery.
Depth of Discharge and Battery Life
The more deeply a battery is discharged on each cycle, the shorter the battery life.
Using more batteries than the minimum required will result in longer life for the
battery bank. A typical life cycle chart is given in the Table below:
T able 3.4. Typical Cycle Life Chart
DEPTH OF DISCHARGE
% OF Ah CAPACITy
CyCLE LIFE OF
GROUP 27 / 31
CyCLE LIFE OF
GROUP 8D
CyCLE LIFE OF
GROUP GC2
10 1000 1500 3800
50 320 480 1100
80 200 300 675
100 150 225 550
It is recommended that the depth of discharge should be limited to 50%.