SamplexPower SEC-1250UL Mode D'emploi page 8

seCtIOn 4 |
For example, when SEC-1250UL is in the Bulk Charge Stage 1, its output voltage is set
at 13.5 VDC. When a battery discharged to say 10.5V is charged, it will try to draw very
large current = (13.5V - 10.5V) ÷ Internal resistance (0.02 Ω) = 150A. SEC-1250UL will,
however, limit this current to 50A.
cHARGinG StAGeS
The battery is charged in 3 stages:
• STAGE 1 -BULK STAGE ("I" Phase),
• STAGE 2 - ABSORPTION STAGE ("U
• STAGE 3 - FLOAT STAGE ("U" Phase)
The 3 charging stages and associated Charging Curves for SEC-1250UL are given at Fig-
ure 4.1 and for SeC-2425UL at fig. 4.2
14.4V
15
14
13.5V
13
12
11
10
9
55 50A
8
50
7
45
6
40
35
5
30
4
25
3
20
15
2
10
1
5
0
0
AMPS VOLTS
8 | SAMLEX AMERICA INC.
Principle of Operation
Stage 1
"I Phase"
B1
A1
B2
A2
80% of
current
capacity
of charger
(40 Amps)
Time, Hours
Figure 4.1 Charging Curve - SEC-1250UL
" Phase) and
o
Stage 2*
"Uo Phase"
Voltage
D1
curve
C1
C2 D2
10% of
current
capacity
of charger
(5A ± 0.5A)
Stage 3
"U Phase"
E1
Current
curve
E2
* Stage 2 time for 4 or 8 hours.