Inverter (DC-AC Converter)
Units that convert the 12 V direct voltage in the service battery to 230 V alternating voltage. They make it possible to run 230 V devices where there is no mains supply; on the other hand the current drawn grows by the voltage ratio, which rapidly increases battery consumption.
The basic conversion relationship comes from conservation of power. A device drawing 500 W on the 230 V side asks for about 42 A on the 12 V side; once the inverter's own efficiency is added, that value rises to 45–50 A. In other words, running a 500 W device for one hour takes about 45 Ah from your battery.
This ratio explains why the inverter is used carefully in an RV: the usable share of a 100 Ah lead-acid bank is around 50 Ah and a single water heater can consume it in minutes. Heat-producing devices are the toughest loads for an inverter.
On the connection side the inverter is wired directly to the battery with short, thick cable through a main fuse close to the battery. The inverter also has its own standby consumption; switching it off when not in use makes sense for battery life. Since the levelling system runs on 12 V DC it needs no inverter, but because they share the same battery bank, the inverter's consumption directly reduces the share left for levelling.
Context in which this term is used: RV automatic levelling guide