Setolite SETO POWER LED Gebrauchsanleitung Seite 27

Explanation of the charging function
The Alpha is the ideal charger for both cyclic and standby charge of rechargeable Lead Acid
Batteries.
The charger works in three different modes. A LED-indicator with three different colours shows the
mode that the charger is in (see more detailed illustration / explanation on next page). Unlike so
called <<taper chargers>>, this model charges with a constant current in the first mode. When the
battery voltage during charging rises to the maximum cycle voltage (e.g. 14.7V), the charger does
not immediately change to standby mode. Instead the charger starts a timer and remains in cons-
tant voltage mode (e.g. 14.7V) until the selected time (e.g. 2h) has elapsed. When the timer starts,
the battery is normally charged to 80-95% of full capacity and can be used at this point if desired.
The timed boost period ensures, however, that the battery will receive the remaining 10 to 20%
capacity in a very short time compared to chargers not having this feature.
The LED indicator changes from red to yellow when timer starts, and changes to green when the
timer period is out. At this point the constant voltage level is reduced to a safe value where the bat-
tery can be left for an unlimited time without risk of overcharge (e.g. 13,8V). This is the float charge
or standby mode.
A primary switch mode technology based on a high efficiency (>80%) flyback topology, allows an
output power as high as 40W. The low leakage current (<100uA) makes it possible to leave the
battery connected to the charger, without mains connected, for more than 6 months, without losing
more than approx 0,4Ah capacity into the charger. A new charging cycle starts when the charging
current rises to the constant current level (e.g. 2.7A). This will happen if the battery voltage drops
because of a load on the battery. The charger will therefore automatically recharge batteries used
in backup systems to their maximum capacity.
14.7V
13.8V
2.7A
CHARGING DIAGRAM
Timer Mode
Red
Yellow
80%
Green
100%
Capacity
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