Specialty Concepts ASC-Plus - Manual (Page 11)

O P E R A T I O N
The operation of the ASC-Plus is completely automatic. No user interface is required
after installation. This controller will regulate the charging of batteries during conditions
of heavy usage, or when left unattended for long periods of time.
SWITCHING SHUNT, PULSE CHARGE REGULATION: - When in the charge mode,
the ASC-Plus allows maximum available array current to flow into the battery through
a blocking diode, lighting the "CHARGING" light. As the battery charges, the voltage
will rise slowly until it reaches about 14.3 volts. At this point, the "CHARGING" light
goes out and battery charging stops. When charging stops the battery voltage will
fall, and when the battery voltage drops to about 13.5 volts, the ASC-Plus will resume
charging.
A TYPICAL DAY: - A typical daily cycle will be as follows. As the charging starts for the
day and battery capacity is low, charging will be continuous. As the battery charges
up, current will pass into the battery for a while and eventually stop. Later, charging
will resume and the system will continue this cycle throughout the day. During the
course of the day, the duration of the charging period of each cycle will get shorter
(cycling on for shorter periods and staying off longer). When the battery is close to
full charge, it will pulse current into the battery to achieve and maintain full charge.
This pulse charging is indicated by the "CHARGING" light occasionally turning on
and off.
LOW-VOLTAGE DISCONNECT (LVD): - The ASC-Plus has a relay that can be used to
prevent deep-discharge damage to batteries. The relay acts as an automatic switch to
disconnect the load before the battery voltage gets too low. The loads are turned off at
the Load Disconnect set-point (11.5 volts) and the loads turn on again at the Load
Resumption set-point (13.0 volts). The “LOAD DISCONNECTED” light indicated that the
loads are disconnected.
RESETTING THE LVD CIRCUIT: - On initial installation, the ASC-Plus will start out with
the LVD relay energized (load disconnected mode). In a 12 volt system, the battery
voltage has to rise to the reset voltage of about 13.0 volts to clear this condition. If the
array is connected to the controller and is producing at least 17 volts open circuit, the
LVD can be reset by disconnecting and then reconnecting the battery positive. The reset
is indicated by the "LOAD DISCONNECTED" light being off.
BATTERY FUSE: - The battery fuse is rated at 15 amps, type: MIN. The fuse will blow
and protect the circuitry from excess current from the array, reverse polarity from the
battery or other wiring problems.