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Model Scope/General Description
The La Marche model A12B Series Filtered Battery Chargers / Power Supplies are engineered for the demanding
requirements of SwitchGear applications, Process Controls, and Communications. The magnetic amplifier circuitry
is designed to carry continuous and intermittent loads up to the maximum rated output. Its robust design,
customizable features, and unmatched reliability have made this workhorse the standard in the industry.
In normal operation, the A12B Battery Charger maintains a constant battery voltage from no load up to 115% its
rated load capacity as indicated by the nameplate. If the external loads exceed nameplate capacity, the charger
will attempt to carry the excess load up to its current limiting capacity. Beyond this point, the battery will carry
the excessive loads. If the battery is discharged, the charger will recharge the battery on a taper curve from its
current limiting capacity to full charge.
The battery charger has a specially designed transformer/reactor combination, which inherently compensates for
variations in the incoming AC power. The impedance balance of the transformer/reactor combination compensates
for a line voltage variation of +/- 10% of the nominal AC voltage specified on the nameplate.
Understanding the Model Number
The A12B model number is coded to describe the features that are included. Find the model number on the
nomenclature nameplate of the charger. Follow the chart below to determine the configuration of the battery
charger.
Optional Accessories Included in the Charger
This charger may have been outfitted with a number of optional accessories or option packages. To determine
the options included (if any) refer to the cover page of the manual package. If the manual package that is included
with the charger is no longer available, contact La Marche and provide the model or serial number of the charger
to receive a list of the included accessories.
