Product Manual

88 | SAMLEX AMERICA INC.
5.7.1.1 Bulk Charge Stage
In the rst stage, known as the "BULK" Charge Stage, the charger delivers the maximum "BULK
CURRENT" (“Io”) that has been programmed using optional Remote Control EVO-RC-PLUS (Refer
to Section 4.4.2.1 of EVO-RC-PLUS manual). Range and Default value are shown at Table 6.2. This
current is delivered to the batteries until the battery voltage approaches its Gassing Voltage i.e.
Absorption Voltage which is typically around 14.4 volts for 12 volt batteries and 28.8 volts for 24
volt batteries. The desired value can be programmed using the optional Remote Control EVO-RC-
PLUS (Refer to parameter "ABSORP VOLTAGE" in Table 6.2 and at Section 4.2.2.2 of EVO-RC-
PLUS manual). The Bulk Charge Stage restores about 75% of the battery’s charge. The Gassing
Voltage is the voltage at which the electrolyte in the battery begins to break down into Hydrogen
and Oxygen gases. Under normal circumstances, a battery should not be charged at a voltage
above its Gassing Voltage (except in the manually selected Equalization Stage) since this will cause
the battery to lose electrolyte and dry out over time.
This stage is displayed as "X-Bulk Stage" in the 2
nd
line of the Charging Mode screens
in the Remote Control EVO-RC-PLUS. Character "X" denotes code for one of 6 of the
Charging Proles that is active. (For details, please see Table 3.2 at Section 3.6.4.2 of the
Owner's Manual for EVO-RC-PLUS).
15
14
13
12
11
10
0
30
28
26
24
22
20
0
Charger Voltage, VDC
TIME
To T1 10 Days
CURRENT (%) of set
BULK CURRENT “Io”
100%
60%
0%
BULK
ABSORPTION
FLOAT
V
Absorp
- 0.3V
Io
(Displayed as
“X-Bulk Stage”)
(Displayed as
“X-Absorption Stage”)
(Displayed as
“X-Float Stage”)
24V Battery 12V Battery
Fig 5.1 Charging Curves for 3 Stage Charging Prole
LEGEND for Fig 5.1
Voltage Curve
Curr
ent Curve
NOTE 1: The voltage curve shows the voltage output of charger. The intrinsic battery voltage
may be different and will be proportional to the state of charge.
The value of the "BULK CURRENT" (“Io”) depends upon the total Ampere Hour (Ah) capacity
of the battery or bank of batteries. A battery should never be charged at very high charging
current as very high rate of charging will not return the full 100 percent capacity as the
Gassing Voltage rises with higher charging current. As a general Rule of Thumb, the BULK
CURRENT “Io” should be limited to 10% to 20% of the Ah capacity of the battery (20
Hr Rate). Higher charging current may be used if permitted by the battery manufacturer.
Programmable range and Default values of "BULK CURRENT" (“Io”) are shown in Table 6.2.
The units are shipped with the "BULK CURRENT" set at the Default Value of 20A for EVO-
1212F / EVO-1212F-HW and 15A for EVO-1224F / EVO-1224-HW.
SECTION 5 | Battery Charging in Evolution
TM
Series