Samplex Europe SEC-1245E, Owner'S Manual

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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 cycle life chart is given at Table 2 below:
Table 2. – Typical Cycle Life Chart
Depth of Discharge Cycle Life Cycle Life Cycle Life
% of AH Capacity Group 27 / 31 Group 8D 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 %
LOSS OF BATTERY CAPACITY AT LOW TEMPERATURES
Batteries lose capacity at low temperatures. At 0º C, a battery will deliver about 70 to 80
% of its rated capacity at 26,7 º C. If the air temperature near the battery bank is lower than
26,7º C, additional batteries will be needed to provide the same usable capacity. For very
cold climates, an insulated / heated battery compartment is recommended.
SERIES AND PARALLEL CONNECTION OF BATTERIES
Series Connection
Fig 1. Series Connection
When two or more batteries are connected in series, their voltages add up but their AH
capacity remains the same. Fig. 1 above shows 4 pieces of 6 V, 200 AH batteries connected
in series to form a battery bank of 24 V with a capacity of 200 AH. The positive terminal of
Battery 4 becomes the positive terminal of the 24 V bank. The negative terminal of Battery
4 is connected to the positive terminal of Battery 3. The negative terminal of Battery 3 is
connected to the positive terminal of Battery 2. The negative terminal of Battery 2 is
connected to the positive terminal of Battery 1. The negative terminal of Battery 1 becomes
the negative terminal of the 24 V battery bank.
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24V Charger
6V
Battery 1 Battery 2 Battery 3 Battery 4
Cable B
Cable A
6V 6V 6V