ADDITIONAL INFORMATION
November 2004 / Masterlink MICC / EN
29
Discharge rates in A:
Charge
5
10 16.7
25
50
75 100 150 200 250 300 400 500
100 100 100 100 100 100 100 100 100 100 100 100 100
100
93
88
85
79
76
74
71
69
67
66
64
63
100
87
78
72
63
58
55
51
48
46
44
42
40
100
84
74
67
56
51
47
41
40
37
36
33
32
100
81
69
62
50
44
41
36
33
31
30
27
25
100
76
61
52
40
34
30
26
23
21
20
17
16
100
71
55
45
32
26
22
18
16
14
13
11
10
Table 3: Percentage of available capacity from a 100 Ah battery at different discharge rates and different
values for “n” (= Peukert exponent).
Example 1
Suppose you have a 200 Ah battery. Now
discharge at a 50 A rate until the battery
reaches 1.75 V per cell (10.5V for a 12 V
battery). This would be equivalent to a
discharge rate of 25 A for a 100 Ah battery.
If the battery delivered 67% (134 Ah) the
appropriate Peukert’s exponent would be 1.25.
Example 2
A 100 Ah battery with a Peukert’s exponent of
1.3 will deliver only 41 % of its capacity (41 Ah)
when supplying a 100A load.
11.2 Time Remaining, CEF, & History.
The Charging Efficiency Factor (CEF) takes into
account the fact that batteries are not 100 %
efficient. You have to put in more energy than
you take out.
All our meters learn the
efficiency of the battery system
. The CEF is
used to correct the rate at which Amp-hours are
counted back during charging. The CEF is also
displayed; a falling CEF is an indication of a
failing battery. Additionally, the historic data
available in the Meter includes the number
battery cycles, and the deepest discharge.
