Ocean Options

There are two different types of generator available for a whole range of uses. Corresponding with a fixed frequency of 50Hz for 230V alternating current as used in Europe, generators operate at a fixed speed (indicated in rpm or revolutions per minute) - either 3000 or 1500. For generators operating at 117 V/ 60 Hz these values will be 3600 resp. 1800 rpm. Half a sine wave is generated every time one of the rotor’s coils goes through the magnetic field of the stator. A 3000rpm generator has two coils, which together produce a whole sine wave: 3000 revolutions per minute divided by 60 seconds equals 50Hz. A 1500rpm generator has four coils to achieve the same result. A relatively large and heavy diesel engine is needed to generate a certain amount of power at a low rpm. The alternator itself will also be heavier due to its four-pole construction (4 coils). On the other hand, however, this type of engine is durable and quiet thanks to its low rpm and heavy construction. It will probably run for more than 20,000 hours before needing an overhaul. Generator sets such as these are used in the professional shipping sector and for vessels intended for permanent use, i.e. rental purposes. If the generator is to be continually operated, we recommend the 1500rpm Whisper, provided you have enough space for installation. A generator set operating at double the speed (3000rpm) is almost half the size and weight of its slower cousin, costing less yet producing the same amount of energy. This is ideal for vessels with limited space or in projects where low weight is important, for example on catamarans or fast sailing/motor yachts built for speed.

Spare parts maintenance kit

Your generator set is an investment that will last many years so it is crucial that spare parts provision is in good hands. Mastervolt supplies all parts for regular maintenance (filters, impellers, etc.) plus parts for repairs and overhauling. Three different service kits are available, starting with A-kits for regular maintenance. As well as covering simple repairs, the more comprehensive B-kits contain spare parts for the water pump, etc. Those embarking on a world cruise and wanting to cover every eventuality can opt for the C-kit, which includes a complete set of gaskets.

Technology: the diesel engine
Mastervolt uses indirect-injected four-stroke diesel engines manufactured in Japan by Mitsubishi and Kubota. Exceptionally quiet, compact and smooth running, these high-tech engines conform to the strictest emission level requirements and are extremely environmentally friendly. The Mastervolt Whisper renders the engines suitable for marine use and the generator, mounting frame and sound shield make the package complete.

Technology: The power section
All Whisper generator sets are fitted with a synchronized alternator. This type of generator is the new standard due to its ability to produce the initial power surge required by inductive appliances such as electric motors and compressors. In addition it has precise voltage regulation and generates a good sine wave. There is no need for a large enclosure with capacitors as usually found on a-synchronized generators. Mastervolt generators do not contain brushes, they regulate their own voltage and are maintenance-free.

Cooling principle
Mastervolt 1500 rpm Whisper generators are fitted with inter-cooling, a system in which water from outside is pumped through a heat exchanger and injected into the exhaust. The engine itself is cooled by a coolant ensuring that no sea water comes into contact with the unit. To achieve the most effective sound insulation, it is almost completely enclosed. The only opening in the casing is for the air needed for combustion. To make all this possible the generator is also water-cooled: a cooler is integrated within the generator enclosure made of seawater-proof materials such as copper-nickel. The combustion air is also cooled to ensure optimum performance even under extreme conditions. The diagram below shows the incoming/outgoing water flow.

Compact as possible
Mastervolt has developed a special technique for keeping Whisper generators as compact as possible. Integrated cooling allows the entire set to be enclosed by a specially designed polyester sound shield with an insulation layer. This offers drastic reductions in the noise level (expressed in decibels). A unique water-cooled exhaust system keeps both exhaust temperatures and noise levels low. In order to save space, all services are connected outside the sound shield as much as possible. 1500 rpm units are powered by water-cooled diesel engines and a fan-cooled alternator section.

Keel cooling/radiator cooling
Optional is keel cooling for boats and radiator cooling for vehicles. The units have a dual cooling system. For both engine and alternator a separate radiator or keel cooler has to be applied. The radiators are a loose supply to be bottom, side or roof mounted. For this applications a complete installation kit is available. Keel cooler kits for steel boats are available as well.

Sound shield canopy
All Whisper generator sets are mounted on rubber mountings into a super damped sound shield canopy. This canopy is solid, very effective and also good looking. Installation is prepared and all fittings are on the side for easy connections. For the smaller units Mastervolt supplies a heavy base plate to absorb vibrations. This base plate could be applied in case of a very light construction of the boat and in vehicles to prevent resonance.