Kussmaul Electronics 091-171 - Manual (Page 2)

INTRODUCTION
Many vehicles come from the factory with only a single battery. Often, especially in emergency
or police vehicles, a considerable number of electrical accessories are installed. This creates
an extreme burden on the battery and results in an unreliable system. In addition to a larger
alternator, it is often desirable to install a second battery. This additional battery can then be
dedicated to the accessory loads and the original battery is then used only for vehicle
operation.
The Model 091-171-12 Add-A-Bat is designed to simplify the installation of a auxiliary battery.
The Add-A-Bat consists of an automatic battery charger, a high current solenoid switch and a
Bar Graph display. The automatic battery charger recharges and maintains the batteries
whenever the vehicle is connected to a 115 volt AC source. The high current solenoid connects
the two batteries so that the alternator charges both when the engine is running while the display
indicates the voltage of each battery and the charger output current.
The accessory loads may be wired to auxiliary battery and thus are completely isolated from
the main vehicle battery. Whenever the vehicle is plugged into “shore power” the battery
charger recharges and maintains the two batteries separately. When the engine is running the
solenoid is energized connecting the two batteries to charge them simultaneously from the
alternator. Thus, a vehicle parked with the engine not running or with insufficient alternator
output, will have its solenoid de-energized and the accessories will only drain the auxiliary
battery. The main vehicle battery is protected and will always be available for engine starting.
Construction of the Add-A-Bat is extremely rugged to withstand the shock and vibration
normally encountered by vehicle mounted equipment. The unit operates completely automatically
and stops charging the batteries when they are fully charged.
There is no trickle charge and therefore no danger of overcharging and water boil-off. Any
parasitic loads on the battery such as radio, lights etc. are automatically supplied with current
from the charger.