Keeping the batteries in good shape can be problematic if owners don’t
take a proactive approach to maintenance. Long periods of storage,
combined with parasitic drains, can lead to inconvenient trip
disruptions and premature replacement of batteries. To avoid this
malady, maintenance chargers are often called into service.
To solve the dilemma of charging the house and starting simultaneously,
Deltran Corporation offers a 2-Bank Battery Maintenance System version
of its popular Battery Tender charger line.
The 2-Bank model, like the single-battery unit, is designed to be
connected to the batteries while a coach is in prolonged storage, and
the charging process is completely automatic.
Output current, up to 1.25 amps for each leg, and voltage is determined
by the condition of each battery. Flashing and steady amber and green
status lights provide a lot of information, including when the battery
needs charging and when the charging is complete. If the lights flash in
alternating green and amber colors, the batteries are likely sulfated
and must be replaced. There are also two status indicator symbols
(graphic of a battery) that work like a fuel gauge in that it shows
charging progress up to the point where the battery is fully charged.
The key to this charger’s efficiency is the multistage charging
electronics. The bulk charge (full power, constant current and
increasing voltage) comes into play when the battery is at 0- to
75-percent charged. An absorption mode (high constant voltage,
decreasing current) kicks in when the battery is 75- to 100-percent
charged. Once the batteries are fully charged, the float stage (low
constant voltage, minimum current) is utilized for long-term
There are two hookup options: alligator clips and permanent
connection. I prefer the permanent connection, which means two ring
connectors at the end of wire leads are secured to the battery
terminals. To use, you simply plug the pigtails from the batteries into
the leads from the charging unit; these cables are also fused. Of
course, the charging unit must be plugged into 120-volt AC power to
The charger can be used for non-sealed (flooded) or sealed (AGM
or GEL) batteries. In the past, I’ve experienced batteries subjected to
long periods of storage lasting in excess of eight years using a
The 2-Bank Battery Tender unit retails for $120, which is cheap insurance when compared to the price of replacement batteries.
For more information, call (386) 736-7900, or go online to Batter Tender.