General Information

Electric power can be compared to water in a river—it requires a source to exist, and differences in altitude to flow. The greater the flow, the more powerful the current will become. Running water provides the capacity to set things in motion: In this process, the current is slowed down—used up, if you like. You can discuss electric current with your Electrician in a similar way, and use the terms to talk about everything required for the proper functioning of all your onboard equipment.

Basic Terms

Electric circuits on board
Both 12V or 24V direct current and 230V/120V alternating current—sometimes combined—are widely used for onboard power.

Direct current: 12 or 24V
Direct current (DC) is most common in batteries. This arrangement is based on a positive and negative pole, with the current flowing in a single direction. Onboard electric circuits mostly function at 12 or 24 Volts. The flow difference in voltage means that higher levels of current intensity require thicker wires. Direct current can be stored in batteries for later use.

Alternating current: 230V/50Hz or 120V/60Hz
You will be familiar with the term Alternating Current (AC) from the electricity grid—most equipment and appliances are designed to run on AC. The polarity of the current constantly alternates, positive turns to negative and visa versa. The standard arrangement in Europe is a voltage of 230 Volt with an alternating frequency of 50 Hertz, while it is 120V with 60HZ in the US. The intensity of the current can be very high even with relatively thin wires. Alternating current cannot be stored for later use, unless it is first converted to direct current.

Electricity generation: generators, alternators and solar power
You are never truly independent onboard a boat until you can generate your own power. This can be done with a generator for 230V alternating current, with an alternator for 12 or 24V direct current, or with solar power.

Power conversion
There are many considerations involved in the proper and durable function of electrical consumers. Choosing the right voltage. Opting for DC or AC. Attaining the right frequency and achieving the appropriate current intensity.

Stored power: batteries and chargers
A power reserve can be stored in a battery and charged through a shore connection, generator, alternator or solar power. The charging process is chemical and must be carefully supervised.

Every Boat Builder/Owner should be aware of the governing bodies in their country or in different parts in the world.
>> Guidelines accepted in Country “A” might not be accepted in Country “B”.

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