Samlex America SEC-2425UL - Manuel (Page 9)

8 | SAMLEX AMERICA INC. SAMLEX AMERICA INC. | 9
seCtIOn 4 | Principle of Operation
Voltage
curve
28.8V
27V
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
0
27.5
25.0
22.5
20.0
17.5
15.0
12.5
10.0
7.5
5.0
2.5
0
AMPS VOLTS
Fig xxx - SEC-2425UL Charging Curves (Absorption 28.8V, Float 27V)
B1 C1
D1
E1
B2 C2 D2
E2
25A
A1
A2
* Étape 2 temps de 4 ou 8 heures.
10% de la
capacité
actuelle
du chargeur
(3A ± 0,5A)
80% de
la capacité
actuelle du
chargeur
(20 ampères)
Temps, Heures
Étape 1
“Phase I”
Étape 3
“La Phase U”
Étape 2*
“La Phase Uo”
Fig. 4.2 Charging Curve for SEC-2425UL
i
inFo
Please note the following important information related to the charging curves
shown in Figs 4.1 and 4.2 above:
1.1 terminal Voltage reading on no load and on load: The output terminals of the
charger consist of one common Negative terminal (3) and two Red Positive terminals
(1, 2) for charging two banks of batteries. Each of the two Positive terminals of the
two banks has Schottky Diode in series for isolation. These isolating diodes have a
current dependent forward voltage drop Vf ranging from 0.2 to 0.3V (at 0.1A) to
0.6V (at 50A). In addition, there will be additional forward drop Vb across the bulk
resistance of the diode and this drop will also increase with increase in charging
current. Please note that the forward voltage drops Vf and Vb occur only when cur-
rent flows through the diode.
1.2 The Float and Absorption voltages are tightly regulated before the isolating
diodes. However, the voltages available at the terminals of the two banks will vary
with the value of the charging current because of the current dependent forward
voltage drop Vf and bulk resistance drop Vb. The Float Voltage before the diodes is,