Dometic Battery-Powered Auxiliary Air Conditioning System - Manual (Page 5)

Batteries
Dometic systems use absorbed glass mat (AGM) batteries, which
can be deeply discharged and rapidly recharged without damaging
the batteries. They are capable of up to 500 discharge-recharge
cycles. The number of batteries will depend on the capacity of the
air conditioner, size of the space to be cooled and user profile of the
truck. Dometic offers a range of choices in external battery boxes that
can be mounted on one of the side rails or between the rails behind
the cab. Replacement AGM batteries are readily available through
battery distributors across North America.
Inverter
Dometic specifies a 2,000 Watt inverter with a Modified Sine Wave
(MSW) output designed for extended periods of operation. This
high-performance inverter is designed to handle the extra load
requirements of the air conditioner as well as house loads. It also
protects the unit from electric spikes that can occur when the
compressor cycles on and off. The inverter can also be ordered with
an optional built-in charger. Most importantly, the inverter has a low-
voltage cutout that automatically turns off 115V AC power whenever
the batteries drop below a preset voltage. This ensures you will
always have sufficient battery power to restart the truck. The inverter
is approximately the same size as a Group 31 battery and is normally
mounted inside the battery box.
Alternator
Dometic’s system uses a high-capacity 270 or 300+ amp alternator
to recharge the batteries when the engine is running. This alternator
replaces the standard alternator on the engine. High capacity is
required in order to recharge the batteries in a reasonable period of
time, 5.5–6 hours. In day-cab applications, recharge must take place
within typical point-to-point runs.
Shorepower
The Dometic system may be ordered with an optional shorepower
connection, allowing you to run the air conditioner on an external
115V power source when available. If the optional combination
inverter/charger unit is installed, you can also recharge the batteries
when plugged into shorepower. TMC recommends a minimum of one
20 amp circuit for shorepower connections. You should use a heavy-
duty cord with a minimum of 12-gauge wire (50 ft.). Remember there
will be a voltage drop across the cord, so use the minimum length
necessary to reach your outside power source.
optional
accessories
Shorepower plug
Group 31 AGM deep-cycle batteries replace house
batteries
High-capacity alternator replaces standard alternator
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