Nanni Generator Type Q4500 – 85ST50

Description

New Nanni Generator Type Q4500 – 85ST50 Marine Generator For Sale

High-Capacity Soundless Marine Power for Superyachts and Professional Vessels

The New Nanni Generator Type Q4500 – 85ST50 Marine Generator is a high-capacity three-phase marine diesel generator developed for superyachts, expedition vessels, passenger craft, offshore-support boats, commercial workboats, and other demanding professional marine applications. Built around a proven John Deere diesel engine and paired with a Leroy-Somer alternator, the the Nanni Q4500 85ST50 combines substantial electrical output, low-speed operation, electronic regulation, and enhanced acoustic protection.

The “ST” designation identifies this model as a Soundless three-phase marine generator designed for installations where reliable onboard electricity must be balanced with improved passenger and crew comfort. Its sound-attenuated enclosure makes it particularly suitable for luxury yachts, liveaboard vessels, hospitality craft, and professional boats that operate their generator sets for extended periods.

The Q4500 – 85ST50 delivers approximately 84.6 kW of prime running power and up to 93 kW of limited-time power at 230/400V and 50 Hz. This capacity makes it suitable for operating high-demand equipment such as marine air-conditioning systems, refrigeration plants, seawater pumps, hydraulic power units, water makers, ventilation equipment, battery chargers, commercial galley systems, and workshop machinery.

For vessel owners seeking a dependable onboard power solution with substantial three-phase capacity, the Nanni Q4500 – 85ST50 provides the performance required for modern yachts and professional marine operations.

Purpose-Built Nanni Q4500 Marine Engineering

The Nanni Q4500 marine generator is engineered as a complete marine power package rather than a general industrial generator adapted for use aboard a vessel. Its diesel engine, alternator, heat-exchanger cooling system, raw-water circuit, wet-exhaust arrangement, digital controls, protection systems, and acoustic enclosure are developed around the demands of marine operation.

The generator is designed to work in environments affected by:

• Continuous vibration
• Saltwater exposure
• High humidity
• Restricted engine-room ventilation
• Changing electrical loads
• Vessel movement and inclination
• Extended operating periods

The Q4500 platform uses a John Deere-based, four-cylinder, four-stroke diesel engine with approximately 4.48 litres of displacement. The engine features electronic regulation and operates at 1500 RPM in the 50 Hz configuration.

This low-speed operating arrangement helps reduce friction, mechanical wear, vibration, and operating noise compared with many higher-speed generator systems. It also supports stable 50 Hz electricity as onboard demand changes.

Customers evaluating the Nanni Generator Type Q4500 – 85ST50 price should consider more than the initial purchase cost. Electrical capacity, acoustic performance, fuel consumption, marine durability, installation compatibility, maintenance access, and worldwide technical support all contribute to the generator’s long-term value.

Heavy-Duty John Deere Diesel Performance

The  Nanni Q4500 85ST50 uses a robust John Deere diesel engine platform designed for sustained electrical production. John Deere engines are widely used in industrial, marine, agricultural, and power-generation applications because of their durable construction and reliable performance.

The generator’s engine configuration includes:

• Four cylinders in line
• Four-stroke diesel operation
• Approximately 4.48-litre displacement
• Electronic engine regulation
• 1500 RPM operation
• Marine heat-exchanger cooling
• EPA/CARB Tier 3 emissions classification

Diesel-powered marine generator sets remain a preferred choice for large yachts and commercial vessels because they provide durable operation, efficient fuel use under suitable loads, and dependable power during extended voyages.

The Q4500 – 85ST50 is designed to provide:

• Stable electricity for high-demand onboard equipment
• Reliable operation under changing loads
• Reduced mechanical stress through low-speed operation
• Practical access for scheduled servicing
• Dependable offshore auxiliary power
• Improved onboard acoustic comfort

A properly sized diesel marine generator allows the vessel’s main engines to remain shut down while onboard electrical equipment continues operating at anchor, during overnight stays, or while working offshore.

Prime and Limited-Time Power Ratings

Understanding the generator’s operating ratings is essential when calculating the vessel’s electrical requirements.

The Nanni Q4500 – 85ST50 provides:

The prime running rating is the more relevant figure when calculating sustained onboard electrical demand. Limited-time power provides additional output for shorter periods and should not be treated as the normal continuous operating capacity.

A vessel’s normal working load should remain below the prime rating, allowing sufficient reserve for temporary load increases and equipment startup requirements.

Electric motors, pumps, compressors, refrigeration systems, hydraulic equipment, and air-conditioning units may require considerably more electricity during startup than during normal running. These temporary demands should be included in the marine electrical load assessment.

An undersized generator may experience overload, voltage instability, overheating, and premature wear. However, selecting a generator significantly larger than required may result in extended operation at very light loads. Correct sizing helps balance capacity, efficiency, and service life.

Stable Three-Phase Electrical Output

The Q4500 – 85ST50 is designed for vessels requiring substantial three-phase marine power. Three-phase electrical systems distribute power efficiently to compatible motors, pumps, refrigeration systems, and other professional marine equipment.

The generator may support:

• Multi-zone air-conditioning systems
• Seawater and freshwater pumps
• Refrigeration and freezer plants
• Ventilation and extraction equipment
• Hydraulic power units
• Water-making systems
• Battery-charging equipment
• Commercial galley machinery
• Workshop tools
• Auxiliary electric motors
• Navigation and communication equipment

The Q4500 range uses Leroy-Somer alternator technology and is configured for 230/400V three-phase output at 50 Hz.

Before installation, a qualified marine electrician should verify voltage, frequency, phase rotation, earthing arrangements, cable sizes, circuit protection, switchboard compatibility, and load distribution.

Single-phase loads can be supplied through a correctly engineered three-phase distribution system, but they should be balanced carefully across the phases. Excessive phase imbalance may reduce available capacity and affect electrical performance.

Fuel Consumption and Operating Efficiency

Nanni’s current product guide lists approximate fuel consumption of 24.6 litres per hour for the Q4500 – 85ST50. Actual fuel consumption will vary depending on connected electrical load, engine condition, maintenance, ambient temperature, fuel quality, and installation.

Fuel-use planning should consider:

• Expected daily operating hours
• Average generator load
• Simultaneous equipment use
• Fuel-tank capacity
• Reserve fuel requirements
• Planned maintenance intervals

A generator operating at reduced demand will generally consume less fuel than one operating near full capacity. However, prolonged operation under extremely light loads should be avoided where possible because diesel engines perform best when regularly operated under a meaningful working load.

Correct generator sizing improves operating efficiency and helps maintain healthy engine temperatures and combustion conditions.

Soundless Technology for Improved Comfort

Noise and vibration are major considerations aboard superyachts, passenger vessels, expedition craft, and liveaboard boats. Generator noise can affect guest cabins, crew areas, lounges, dining spaces, and working environments.

The Q4500 – 85ST50 belongs to Nanni’s Soundless marine generator range. Its acoustic enclosure is designed to reduce airborne engine noise, alternator noise, and vibration transmission while retaining access to essential service components.

Nanni’s product guide lists the Soundless Q4500 enclosure at approximately:

These figures apply to the Q4500 Soundless range, including the 85ST50. Final measurements and lifting weight should be confirmed using the approved technical drawing before installation.

A correctly installed quiet marine generator should also include:

• Flexible anti-vibration mounts
• Effective engine-room ventilation
• Properly supported hoses and cables
• An engineered wet-exhaust system
• Adequate acoustic insulation
• Correct service clearances

The enclosure alone does not determine final onboard noise. Hull structure, mounting quality, ventilation openings, and exhaust design also influence acoustic performance.

Marine Cooling for Extended Operation

Reliable cooling is essential for dependable marine generator performance. Unlike land-based generators operating in open surroundings, onboard generators are normally installed within enclosed machinery spaces.

The Q4500 uses a marine cooling arrangement designed to maintain stable engine temperature during sustained operation. The system includes a closed coolant circuit, heat exchanger, raw-water pump, and wet-exhaust configuration.

A properly maintained marine generator cooling system supports:

• Stable engine operating temperature
• Efficient heat transfer
• Reliable output under sustained loads
• Reduced thermal stress
• Protection of internal engine components
• Longer service life

Routine maintenance should include checking coolant condition, seawater strainers, raw-water flow, hoses, clamps, drive belts, pump impellers, heat-exchanger components, and exhaust connections.

Restricted seawater flow, blocked heat-exchanger passages, damaged impellers, or inadequate machinery-space ventilation may cause overheating even when the generator is correctly sized.

Digital Generator Control and Monitoring

The Q4500 platform uses Nanni’s SI-2 digital control system for generator operation and supervision. The panel allows operators to start and stop the generator, monitor important engine and electrical parameters, review status information, and identify alarms or fault conditions.

Depending on configuration, monitoring functions may include:

• Engine speed and temperature
• Oil-pressure monitoring
• Voltage and frequency display
• Current and load monitoring
• Alarm and fault-code display
• Operating-hour records
• Generator protection functions
• Remote monitoring compatibility

Digital monitoring helps operators identify abnormal conditions before they develop into serious failures. However, it does not replace physical inspection or scheduled preventive maintenance.

Applications of the Nanni Q4500 – 85ST50

The generator is suitable for several demanding marine applications.

Superyachts and Large Motor Yachts

The unit can support multi-zone air conditioning, refrigeration equipment, electric galley systems, water makers, pumps, battery charging, entertainment systems, lighting, and guest-comfort services.

Expedition and Long-Range Vessels

Its substantial prime-power rating makes it suitable for vessels operating for long periods away from shore facilities.

Passenger and Hospitality Vessels

The Soundless generator configuration can support passenger-comfort systems, ventilation, refrigeration, lighting, catering equipment, and other hospitality-related loads.

Commercial Workboats

The generator can serve as a dependable commercial marine generator for pumps, hydraulic equipment, refrigeration, workshop machinery, communication systems, and operational equipment.

Marine Refit Projects

The Q4500 – 85ST50 may be considered when replacing an ageing, undersized, inefficient, or noisy generator, provided the vessel’s electrical and installation systems are compatible.

Technical Specifications of the Nanni Q4500 – 85ST50

These specifications are drawn from Nanni’s current generator product guide. Final technical data, alternator configuration, optional equipment, and installation drawings should be confirmed before ordering.

Standard Equipment and Available Options

The Nanni Q4500 – 85ST50 is supplied as an integrated marine diesel generator set.

Typical equipment may include:

• John Deere four-cylinder diesel engine
• Leroy-Somer three-phase alternator
• Electronic engine-speed regulation
• SI-2 digital control panel
• Marine heat-exchanger cooling
• Raw-water circulation components
• Wet-exhaust arrangement
• Fuel and oil filtration
• Generator protection systems
• Soundless acoustic enclosure
• Flexible mounting system
• Operating documentation

Available options may include:

• Fuel pre-filter
• Siphon-break equipment
• Remote monitoring equipment
• Alternative electrical arrangements
• Additional marine installation accessories

The final equipment package should be confirmed at quotation stage because vessel requirements and regional specifications may vary.

Genuine Nanni Supply and Worldwide Support

Customers looking for the New Nanni Generator Type Q4500 – 85ST50 Marine Generator for sale can contact our specialists for current availability, technical guidance, approved drawings, export documentation, and international delivery arrangements.

We support customers with:

• Genuine Nanni generator supply
• Generator sizing guidance
• Electrical-load assessment support
• Replacement generator evaluation
• Export documentation
• Worldwide shipping
• After-sales assistance

Nanni maintains an international network operating across approximately 90 countries with hundreds of qualified partners supporting customers throughout the generator’s operating life.

Frequently Asked Questions

What is the Nanni Q4500 85ST50 price?

The Nanni Generator Type Q4500 – 85ST50 price depends on current availability, configuration, optional equipment, shipping destination, and export requirements. Contact our team for an updated quotation.

How much power does the Q4500 – 85ST50 provide?

The generator provides approximately 84.6 kW of prime running power and up to 93 kW of limited-time power.

Is it a three-phase marine generator?

Yes. It provides 230/400V three-phase marine power at 50 Hz.

What engine does it use?

The Q4500 range uses a four-cylinder John Deere diesel engine with approximately 4.48 litres of displacement and electronic speed regulation.

What does “ST” mean?

“ST” identifies the generator as a Soundless three-phase model designed to reduce onboard noise and vibration.

Can it replace an existing yacht generator?

Yes. It may be suitable for a marine generator replacement when output, voltage, phase, dimensions, cooling, exhaust, fuel, mounting, and switchboard requirements are compatible.

Request a Quote for the Nanni Q4500 – 85ST50

the Nanni Q4500 85ST50 Marine Generator is a capable choice for superyacht owners, shipyards, vessel managers, and professional operators requiring high-capacity three-phase marine power with enhanced acoustic performance.

Contact our marine generator specialists to request the latest the Nanni Q4500 85ST50 price, confirm availability, review installation requirements, and select the correct generator configuration for your vessel.