SYSTEM VOLTAGES
ADVANTAGES OF A 24V OVER 12V SYSTEM
When we planned the electrical systems on the new Seawind 1370 we knew there would be crucial considerations and careful planning required. There are 2 major systems aboard – the DC low voltage system, and the AC high voltage.
Most people will be very familiar with 12 volt DC power on boats. It carries most of the most interesting day-to-day systems – lights, refrigeration, sailing instruments – it’s the mainstay on most smaller vessels. After considering the list of options ordered on this new model, we then analyzed current loads experienced by the 12 volt systems and modelled them against our smaller and larger boats. It then became very clear that the 1370 is an altogether different animal – with the number of devices and the increase in power consumption and charging, our conventional 12 volt system would be running at capacity on many of the boats on order, and near enough to it on others. Crucially, this meant we would be using the maximum size of cable available – physically the cable calibre is at the max, and the interconnecting components would also be at or beyond their maximum load limits. This also meant we lost the requisite safety margin – meaning the boat owner would lack the ability to further expand the system later. Of greater importance was the question mark over the reliability of the system.
The solution is to move to a higher voltage 24-volt system. This immediately cuts our current draws by 50%, and solved most of our most urgent concerns. We now benefit from faster battery charging and allows more options for us to work with between the different electrical systems. Of great importance to Seawind is our focus on maintaining performance as well as reliability. And a well-known advantage to a 24-volt system is the weight – through the reduced wiring mentioned earlier. Depending on the optional equipment selected by the owner, the weight saved ranges from 150 to 200kg.
SYSTEM VOLTAGES
AC HIGH VOLTAGE
For the AC power on board we had to review 2 separate voltages: 120 volt for customers in the USA, and 230 volt for the rest of the world. As with the DC appliances, the large quantity and variety of AC-power devices being specified for these boats forced us to look closely at what we had been offering in the past and what would be best for the long term. We have now settled on having 2 separate circuits on board for both the 230V and the 120V systems. With the 120V we had reached our single-circuit limits, so by separately into 2 circuits and we are now able to run the vast majority of items on sailors shortlists. We have also changed our shore power and generator over to 240/120V. This will now mean we can run both of the 120V circuits on board – powered by either a single shore power cable, the generator or either of 2 inverters. For 230V customers, we have a single 32-amp shore power supply, a generator and 2 inverters to run the high-powered devices.
Seawind will continue to reevaluate the electrical systems on board the 1370 as time passes and new devices and electrical equipment for the systems become available. Rest assured we’re putting in the “hard yards” now, before boats begin construction. And we’ll keep working hard to make sure our boats are future-proofed as well as being built to last.