Samlexpower PST-1500-48, Руководство пользователя

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TABLE 7.2: DISCHARGE CURRENT RATES - “C-RATES” (continued from Previous page)
Hours of discharge time “T” till
the “End Point Voltage”
"C-Rate" Discharge Current in Amps =
Capacity "C" in Ah
÷
Discharge Time
"T" in Hrs.
Example of C-Rate
Discharge Currents
for 100 Ah battery
8 Hrs. (UPS application) C/8 or 0.125C 12.5A
10 Hrs. (Telecom application) C/10 or 0.1C 10A
20 Hrs. (Automotive application) C/20 or 0.05C 5A
100 Hrs. C/100 or 0.01C 1A
NOTE:
When a battery is discharged over a shorter time, its specified “C-Rate” discharge current will
be higher. For example, the “C-Rate” discharge current at 5 Hour discharge period i.e. C/5 Amps will
be 4 times higher than the “C-Rate” discharge current at 20 Hour discharge period i.e. C/20 Amps.
7.7 CHARGING / DISCHARGING CURVES
Fig. 7.1 shows the charging and discharging characteristics of a typical 12V / 24V / 48 Lead
Acid battery at electrolyte temperature of 80°F / 26.7°C. The curves show the % State of
Charge (X-axis) versus terminal voltage (Y-axis) during charging and discharging at differ-
ent C-Rates. Please note that X-axis shows % State of Charge. State of Discharge will be =
100% - % State of Charge. These curves will be referred to in the subsequent explanations.
Lead-Acid Battery Chart - 80˚F / 26.7˚C
Battery V
oltage in VDC
Battery State of Charge in Percent (%)
0 10 20 30 40 50 60 70 80 90 100 110 120 130
16.5
16.0
15.5
15.0
14.5
14.0
13.5
13.0
12.5
12.0
11.5
11.0
10.5
10.0
9.5
9.0
C/5
C/40
C/20
C/10
DISCHARGE
CHARGE
C/20
C/3
C/5
C/10
C/100
33.0
32.0
31.0
30.0
29.0
28.0
27.0
26.0
25.0
24.0
23.0
22.0
21.0
20.0
19.0
18.0
66.0
64.0
62.0
60.0
58.0
56.0
54.0
52.0
50.0
48.0
46.0
44.0
42.0
40.0
38.0
36.0
24V 48V 12V
Fig. 7.1: Charging / Discharging Curves for 12V / 24V / 48V Lead Acid Batteries
SECTION 7 | General Information on Lead Acid
Batteries