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This charger features user selectable 2 or 3 stage charging. The charging profile is selected by
turning the switch on the front panel to 3 stage or 2 stage charging.
A two-stage charger provides a constant current until the battery reaches its rated capacity
and then switches to a “float” voltage. The current then reduces as necessary to maintain
the battery at the float voltage. The charger can be connected to the battery indefinitely and
will provide the appropriate profile. A two-stage charger is recommended in most instances
since it is the most versatile and can be permanently connected to attenuate the characteristic
discharge of unused batteries. A load can be put on the battery or batteries without altering its
ability to keep the battery at optimal charge.
A three-stage charger is the fastest charger. It charges the battery at a constant current until
the battery voltage reaches a slightly elevated level. The battery is maintained at this voltage
while the charging current diminishes to a low value, and then the battery is switched to the
float voltage where it can be maintained indefinitely. However, the charger cannot differentiate
between a current going to a load on the battery, or being absorbed by the battery, so it can
overcharge a battery supplying current to a load. A two-stage charger is preferred for “loaded”
batteries and a three-stage for idle or unloaded batteries during recharging.
All of Analytic Systems’ chargers include adjustable output voltage for charging standard or
deep cycle lead-acid, VLRA or gel type batteries.
2 or 3 Stage Charging
100%
75%
50%
25%
0%
Bulk
(Constant Current)
Maintenance
(Constant Volts)
Time
Two Stage Charger
Volts
Amps
100%
75%
50%
25%
0%
Bulk
(Constant Current)
Absorption
(Constant Volts)
Maintenance
(Constant Volts)
Time
Three Stage Charger
Volts
Amps
