Samlex America SCC-1208L - Manuel (Page 7)

6 | SAMLEX AMERICA INC. SAMLEX AMERICA INC. | 7
SeCtIOn 2 | Features of the SCC-1208l
Voltage to ensure that the battery is fur-
ther charged to the full capacity without
overcharging. The Absorption Stage
restores the balance 20% of the capacity.
As the output voltage of the controller
is held constant, the battery absorbs the
charge slowly and the current reduces
gradually till all of the soft Lead Sulfate
(PbSO
4
) crystals have been converted to
Lead Dioxide (PbO
2
) on the Positive Plates
and Sponge Lead (Pb) on the Negative
Plates.
In SCC-1208L, the Absorption Stage
is a constant voltage stage of
14.8 V +/- 0.2 V for Flooded Battery and
14.5 V +/- 0.2 V for Sealed AGM battery
(at 25° C).The constant current from
the Solar Panel is not fed to the battery
continuously but in pulses of varying
pulse width at frequency of 30 Hz. This
technique allows the current to be ef-
fectively “tapered” as the battery gets
charged and the result is equivalent to
constant voltage charging. For a battery
entering the Absorption Stage at around
80% charged state, the “On Time” pulses
would be very long and almost continu-
ous. As the charge state approaches the
end of Absorption and beginning of the
Float Stage, it may just “tick” and send
very short pulses to the battery.
When the battery reaches the Absorption
Voltage, the PWM begins to hold the volt-
age constant. This is to avoid over-heating
and over-gassing the battery. The current
will taper off to safe levels as the battery
becomes more fully charged.
This stage will remain active for around 1
Hour and then the controller will transi-
tion to the Float Stage.
Stage 3 – Float Stage
When a battery becomes fully charged,
dropping down to the float Stage will
provide a very low rate of maintenance
charging while reducing the heating and
gassing of a fully charged battery. When
the battery is fully recharged, there can
be no more chemical reactions and all the
charging current is turned into heat and
gassing. The purpose of the Float Stage
is to protect the battery from long-term
overcharge. From the Absorption Stage,
charging voltage is dropped to the Float
Stage voltage of 13.8 V ± 0.2. During this
stage, PWM pulses are of very short dura-
tion at frequency of 30 Hz.
In the case the battery voltage drops
below 12.5 VDC, a new cycle of Bulk,
Absorption and Float will start.
night Light Function
This unit has a facility where DC loads
that are connected to the Load Terminals
will automatically be switched on at night
(Solar Panel voltage ≤ 3 V for at least
10 min) and switched off during day time
(solar Panel voltage ≥ 4 V for at least
10 min.) This type of load generally
consists of night lighting. The continuous
load capacity is 8 A maximum (10 A for
5 min). In case the load is higher than
12 A, the load will be switched off and
will reset automatically once the load
current is reduced. It will reset automati-
cally 2 times* and after that, a manual
reset will be required that will involve
disconnecting the Solar Panel and the
battery connections (*Note: time interval
between the 1st auto-reset and the 2nd
auto-reset is around 1 minute).