Which battery is the right one?

Following is an example for calculation of any consumer, which helps the user to develop his energy balance:

2 Halogen Lamps 12 V (Volts) / 30 W (Watts) each : Capacity (total)
60 W divided by the voltage 12 V = current intensity 5 A (Amperes)
Time of use / day in hours (h) e.g. 4 h x 5 A = 20 Ah

This calculation has to be made for each consumer. The total capacity is the sum of all results. In case of lead-acid batteries, this value is multiplied by the factor 1.7, in case of AGM/fleece batteries, the value is multiplied by the factor 1.4, and in case of gel batteries, the value is multiplied by the factor 1.3. The result is the minimum nominal capacity (in ampere-hours Ah), the battery should have.

Normal starter batteries are not designed for cyclic load.
Thus, they cannot be recommended as board batteries.
For the load in campers, intervention vehicles and boats we are exclusively offering cycle resistant batteries.

Which VOTRONIC charger is the right one?

The units of series "Pb" are designed for the leisure range, such as campers and boats, while the professional series "VAC" is particularly adapted to the requirements in intervention vehicles to ensure permanent readiness for use. For a long time, battery manufacturers were indicating the recommendable charging capacity for their batteries with 10 % of the used battery capacity (Ah).

Nominal capacity of battery 100 Ah, 10 % of it = 10 A charging current should be supplied by the charger.

Contingent on increase of comfort and more electrical consumers in the vehicle, nowadays a value of about 14 % is more realistic. The reason is the simultaneous supply of the consumers (refrigerator, lighting, TV) during battery charging, which is resulting in a reduction of the actual charging capacity. Consequently, this consumption has to be considered for dimensioning of the charger's charging capacity by up to 40 % to achieve a sufficient and quick charging, treating the battery carefully at the same time. On principle, the charger should never be chosen "too small", because overcharging of the battery is not possible and the number of consumers is increasing continuously.

Nominal capacity of battery 100 Ah, 14 % of it = 14 A charging current should be supplied by the charger.

Due to their intelligent full battery recognition, VOTRONIC chargers are covering a very wide range of battery capacities. Further details concerning the values can be drawn from the unit tables.

Keyword "Total Discharge"

Apart from insufficient charging by an inappropriate charger, the total discharge should not be underestimated in connection with quick ageing or premature failure.

Very often, this is caused by consumers, which have not been switched-off, "hidden" discharge in the mA range by e. g. tracking current in case of humidity despite of disconnected main switch, electromagnetic stop valves of heaters or "silent" consumers, such as clocks, control panels and units in stand-by mode.

The VOTRONIC delivery program comprises different battery control units, such as e. g. battery computer and battery protector (protection against total discharge) to prevent an imminent total discharge of the supply battery. If a battery should be replaced, it is recommendable to check the existing power supply concept and to develop an energy balance to be able to considering also consumers being eventually installed later.

Total discharge of a 12 V lead battery and consequently damage
starts already from a battery voltage of less than 10.5 V


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