A second on-board battery in the motorhome increases the independence from the shore power and is virtually on long trips. We looked at the installation at Caravan Metropol in Bautzen.
Especially older campers often lack in battery capacity. If space is available, a second energy storage can but fairly easy to retrofit – best if already pending an exchange, because the secondary battery needs in terms of type, manufacturer and capacity in accordance with the first.
In addition, the existing battery should be no longer than half a year in operation. In practice, this means that usually two new batteries. In addition to the space – as close to the primary battery – you should keep the load of the automobile in mind here.
First you made depending on an additional positive and negative cables. The cable cross-section of the rule of thumb: The line should be at least as thick as the thickest cable else in the vehicle. A cross-section of 35 square millimeters is sufficient as a rule. The positive lead is marked with a red shrink tube, blue connects the negative poles. Before installing, ensure that current no longer flows.
The correct wiring and connection sequence is crucial: Only one connects the positive poles of the batteries, then the negative terminals. The positive cable of the vehicle is connected to the battery one, the negative leads to battery two – which avoids an unequal burden.
An isolated end wrench ensures safety when working at the poles. Finally, you can protect the positive poles. The charger must have enough charging current – at least ten percent of the battery capacity – provide with the appropriate characteristics.