Campbell Scientific PS200/CH200 12 V Charging Regulators - Manual (Page 58)

PS200/CH200 12 V Charging Regulators
fully charged battery was swapped in replacing an old battery which suffered
from a significant Qloss. During cycle charging if the battery charge current
falls below C/100, then cycle charge will be terminated and Qloss will be
zeroed.
0 5 10 15 20
12
12.6
13.2
13.8
14.4
15
0
0.24
0.48
0.72
0.96
1.2
Time in Hours
Battery Voltage (Volts) Battery Current (Amps)
14.743
12.332
Vbatt
1.013
0.029
Ibatt
19.667 0 Hours
FIGURE 7-1. 2 step constant voltage battery charging by
PS200/CH200
7.2 Maximum Power Point Tracking
The current and power versus voltage for a 70 W solar panel are illustrated in
FIGURE 7-2. As can be seen from the figure, a Maximum Power Point of
operation exists for solar panels. Adjusting the load on the solar panel so it
operates at this Maximum Power Point is referred to as Maximum Power Point
Tracking (MPPT). MPPT is beneficial when insufficient power is available
from the charge source, which is the case during current limited charging. The
somewhat noisy charging current and voltage observed in FIGURE 7-1 during
the initial current limited charging stage is due to the MPPT algorithm of the
PS200/CH200 searching for the maximum power point of the associated solar
panel.
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