When I first started working with backup power systems fifteen years ago, I thought generators were pretty much one-size-fits-all machines. You picked a power rating, chose between open or enclosed, and called it a day. But after years of spec’ing power solutions for hospitals, data centers, manufacturing plants, and everything in between, I’ve learned the truth: custom diesel generator configuration is where the real value lives.

The short answer to whether you can customize a Cummins generator? Absolutely yes—and in more ways than most people realize. From control system options and custom voltage 480v 3-phase outputs to soundproof generator enclosures and multi-generator paralleling, Cummins and manufacturers like Tesla Power offer an impressive range of customization capabilities that can make the difference between a generator that merely works and one that perfectly fits your operation.

In this article, I’m going to walk you through exactly what’s customizable, what matters most for different applications, and how to navigate the customization process without overspending or overlooking critical requirements. Whether you’re replacing an aging backup system or designing power infrastructure for a new facility, understanding your customization options is essential to getting it right.

Professional installation of multiple large-scale Cummins diesel generators in an industrial facility, demonstrating the scope of custom power generation systems for mission-critical applications.

Understanding Generator Customization: What Does It Actually Mean?

Let me start with what customization isn’t. It’s not about slapping a different paint color on a standard unit or adding a company logo. Real Cummins generator customization means engineering the system to match your specific operational requirements—voltage, frequency, control architecture, environmental constraints, runtime needs, and integration with existing infrastructure.

The Difference Between Standard and Custom Configurations

Most manufacturers, including Cummins, Caterpillar, and Kohler, offer “standard” generator packages that cover common applications. These typically come in preset power ratings (50 kW, 100 kW, 250 kW, etc.) with standard voltages (120/240V single-phase or 480V three-phase), 60 Hz frequency for North America, and basic control panels.

Customization enters the picture when your requirements deviate from these standards. Maybe you need 50 Hz frequency for international equipment compatibility. Or perhaps you’re installing generators on a rooftop with strict noise ordinances, requiring a custom quiet diesel generator solution. Sometimes it’s about diesel generator parallel operation with load sharing between multiple units for N+1 redundancy configuration.

What’s Actually Customizable?

Through my projects with Tesla Power and other suppliers, I’ve seen customization touch nearly every system:

• Electrical output specifications: Voltage, frequency, phase configuration, and power factor
• Control and monitoring systems: From basic start/stop to sophisticated PowerCommand digital control with remote access
• Mechanical packaging: Soundproof generator enclosures, weatherproof generator housing, trailer mounting, containerization
• Fuel systems: Extended fuel tank capacity, day tanks, multiple fuel sources, fuel polishing
• Paralleling and switchgear: Paralleling switchgear solutions for multiple units, automatic transfer switch (ATS) configurations
• Cooling systems: Radiator sizing for high-altitude or high-temperature environments
• Emissions controls: Tier 4 final emissions compliance for regulated areas

The key is understanding which customizations deliver actual operational value versus which are nice-to-have features that inflate costs without meaningful benefit.

Customizing Control Systems and Monitoring

If there’s one area where customization delivers outsized value, it’s the control system. The difference between a basic genset controller and a fully integrated generator control system can transform how your facility manages power during outages.

Basic vs. Advanced Control Options

Basic controllers handle essential functions: automatic start on utility failure, engine monitoring (oil pressure, coolant temperature), and shutdown on fault conditions. They work fine for simple applications—a small retail store, a remote cell tower, or a residential backup system.

But when you move into mission-critical facilities, you need more. That’s where systems like PowerCommand digital control come in. I’ve specified these on hospital projects where we needed:

• Real-time engine and alternator performance data
• Historical data logging for predictive maintenance
• Remote alarm notification via cellular or ethernet
• Integration with building management systems (BMS)
• Multi-language displays for international facilities

Generator Remote Monitoring System

One of the most valuable customizations I recommend is adding generator remote monitoring system capability. Modern platforms like PowerCommand Cloud or similar systems from Caterpillar and Kohler let you check generator status from anywhere. During Hurricane season a few years back, I had a client with generator sites across three states. Instead of dispatching technicians to physically check each unit during power events, we monitored everything remotely—fuel levels, load percentages, runtime hours, even GPS location for mobile units.

Key Insight: Remote monitoring typically adds 10-15% to control system costs but can reduce emergency service calls by 40% and prevent failures through early fault detection.

Automatic Voltage Regulator (AVR) Customization

The AVR (automatic voltage regulator) maintains stable output voltage as loads fluctuate. Standard AVRs work for most applications, but sensitive equipment—medical imaging devices, precision manufacturing equipment, server farms—may require enhanced AVR systems with tighter voltage regulation (±0.5% instead of standard ±1-2%).

I once worked on a data center backup power project where voltage stability was non-negotiable. We specified Cummins generators with precision AVRs that could handle sudden load steps (when servers kicked on) without voltage sag. Cost difference? About $3,000 per unit. Value to the client? Avoiding even one server crash during switchover paid for the upgrade ten times over.

Control Panel Customization

Beyond the electronics, the physical custom generator control panel matters too. Considerations include:

• Mounting location: Engine-mounted vs. remote-mounted panels
• Environmental rating: NEMA 1 (indoor), NEMA 3R (outdoor), NEMA 4X (corrosive environments)
• Display type: LED indicators vs. full-color touchscreens
• Custom switch/meter layout: For operator-specific workflows
• Multiple control points: Local and remote control stations

For a manufacturing plant upgrade, we installed remote control panels in the facility manager’s office and the main electrical room, both controlling the same generator pair. This eliminated the need to walk outside to the generator pad in all weather conditions.

PowerCommand digital control interface displaying real-time operational data, paralleling controls, and comprehensive system monitoring capabilities—the nerve center of modern custom generator installations.

Voltage, Frequency, and Power Output Configuration

This is where things get technical, but stick with me—understanding electrical customization is crucial for avoiding expensive mistakes.

Custom Voltage Configurations

North American standard voltages are well-known: 120/240V single-phase for residential, 208V or 480V three-phase for commercial and industrial. But what if your facility has equipment imported from Europe (400V), legacy machinery (440V), or specialized processes requiring non-standard voltages?

Cummins generators can be configured for virtually any voltage output through alternator winding customization and transformer integration. Common custom voltage configurations I’ve specified include:

• 400V 3-phase 50Hz: For European equipment compatibility
• 600V 3-phase: For heavy industrial motors and Canadian installations
• Multiple voltage outputs: Dual 480V and 208V from the same unit via transformer
• High-voltage: 4160V, 13.8kV for utility-scale or campus distribution

The alternator is the key component here. Manufacturers like Stamford, Leroy-Somer, and Marathon (commonly paired with Cummins engines) offer flexible winding configurations. Cost impact varies—adding a secondary voltage via transformer might add $5,000-$15,000, while a complete custom alternator winding could add 15-20% to generator cost.

Frequency Customization: 50Hz vs. 60Hz

Here’s something that trips people up: frequency isn’t just a setting you flip on a switch. Generator frequency is determined by engine RPM and alternator pole configuration, following this relationship:

Frequency (Hz) = (Engine RPM × Number of Poles) / 120

For 60 Hz output (North America standard), you typically need:

• 2-pole alternator @ 3600 RPM
• 4-pole alternator @ 1800 RPM

For 50 Hz output (Europe, Asia, Africa, parts of South America):

• 2-pole alternator @ 3000 RPM
• 4-pole alternator @ 1500 RPM

I once had a client manufacturing products for export who needed to test equipment under both 50Hz and 60Hz conditions. We specified a dual-frequency generator that could run at either 1500 RPM or 1800 RPM through governor adjustment. It wasn’t cheap—about 25% more than a single-frequency unit—but it eliminated the need for two separate generators.

Important: You can’t just “convert” 60Hz to 50Hz electrically without expensive frequency converters. If you need both, either buy two generators or specify a dual-RPM custom unit from the start.

Power Factor and Reactive Power

Most generators are rated for 0.8 power factor (PF), meaning they deliver their rated kW at 0.8 PF. But motors, transformers, and some electronic loads have lower power factors, requiring more reactive power (kVAR).

If your facility has heavy motor loads or you’re supporting a campus with multiple buildings, you might need a generator with enhanced reactive power capability. This typically means oversizing the alternator or adding power factor correction equipment. I’ve seen this requirement on wastewater treatment plants (lots of pump motors) and older manufacturing facilities with legacy equipment.

Paralleling Different Voltages and Frequencies

One question I get frequently: “Can we parallel generators with different specs?” Short answer: voltage and frequency must match. You cannot parallel a 480V generator with a 400V unit, or a 60Hz generator with a 50Hz unit. Phase rotation, voltage magnitude, and frequency must all sync within tight tolerances for generator synchronization methods to work.

Paralleling and Redundancy Solutions

When uptime is non-negotiable—hospitals, data centers, critical manufacturing—a single generator becomes a single point of failure. That’s where multi-generator paralleling and redundancy configurations come in.

What is Generator Paralleling?

Diesel generator parallel operation means connecting two or more generators to a common electrical bus so they share the total load. Instead of one 1000 kW unit carrying everything, you might have two 600 kW units each carrying 500 kW, with capacity to spare.

This requires sophisticated synchronization:

1. Voltage matching: All units must output the same voltage magnitude
2. Frequency synchronization: All units must run at identical frequencies
3. Phase alignment: The AC waveforms must be in phase
4. Load sharing: Active and reactive power must be distributed proportionally

Load Sharing Methods

There are two primary approaches to load sharing control system design:

1. Droop (Speed Droop) Load Sharing

This is the simpler, more robust method. Each generator’s frequency decreases slightly as it picks up more load. Generators naturally balance to equal loading without communicating with each other. Think of it like springs supporting a weight—each compresses until forces equalize.

Pros: No communication wiring between units; more fault-tolerant; works even if one controller fails

Cons: Less precise load sharing (±5-10% imbalance); frequency varies slightly with total load

I use droop control for most industrial applications where precise load distribution isn’t critical.

2. Isochronous Load Sharing

Also called “active load sharing,” this method uses communication wires between generator controllers to maintain constant frequency while actively balancing loads. One generator operates as the “master” controlling frequency; others follow and share load proportionally.

Pros: Precise load sharing (±1-2%); constant frequency regardless of load

Cons: Requires communication cabling; master failure can disrupt system; more complex troubleshooting

For hospital standby power system projects, I always specify isochronous load sharing to meet tighter regulatory requirements under NFPA 110 compliance.

Redundancy Configurations

Redundancy isn’t just about having backup—it’s about system architecture. Here are the common configurations:

N Configuration: Exactly enough capacity to handle the load. No redundancy.

• Example: 1000 kW load, one 1000 kW generator
• Risk: Any failure = complete outage

N+1 Configuration: One extra generator beyond minimum requirements.

• Example: 1000 kW load, two 600 kW generators (one can be offline for maintenance)
• Most common for critical facilities
• Allows maintenance without vulnerability

N+2 Configuration: Two extra units.

• Example: 1000 kW load, three 500 kW generators
• For ultra-critical applications or extended maintenance windows

2N Configuration: Complete system redundancy.

• Example: 1000 kW load, two completely separate 1000 kW systems
• Highest reliability but also highest cost
• Common in Tier IV data centers and mission-critical military/government facilities

I specified N+1 redundancy configuration for a regional hospital’s emergency power. They had three 750 kW Cummins generators supporting a 1500 kW critical load. Any single unit could fail or be taken offline for maintenance while still meeting full load capacity plus margin.

Paralleling Switchgear

The hardware that makes paralleling work is the paralleling switchgear solutions package—essentially a cabinet containing:

• Generator circuit breakers
• Synchronizing controls
• Protective relays
• Metering and monitoring equipment
• Bus bars for power distribution
• Transfer switches (if applicable)

Customization options include:

• Low-voltage vs. medium voltage switchgear: 480V/600V vs. 4160V/13.8kV
• Main-tie-main configurations: For systems with utility plus multiple generators
• Bus topology: Isolated bus, common bus, split bus with tie breaker
• Automatic Transfer Switch (ATS) integration: Closed transition transfer switch for “make-before-break” seamless transfer

Tesla Power and other quality manufacturers offer pre-engineered paralleling packages for common configurations, or fully custom-engineered systems for unique requirements. A pre-engineered 3-generator, low-voltage paralleling switchgear package might run $40,000-$80,000, while a custom medium-voltage system for a data center campus can easily exceed $500,000.

Commercial-grade paralleling switchgear installation featuring digital control panels, circuit protection devices, and synchronization equipment for coordinating multiple generator systems in parallel configuration.

Enclosure and Acoustic Customization

Not all generators live in climate-controlled equipment rooms. Many end up on rooftops, outdoor pads, or sites with strict noise regulations. That’s where enclosure customization becomes critical.

Soundproof Generator Enclosures

Standard open-frame generators produce 100-105 dB(A) at 7 meters—about as loud as a chainsaw. That’s fine for remote industrial sites but completely unacceptable for urban hospitals, schools, or residential areas.

Custom quiet diesel generator solutions use multi-layer acoustic enclosures to achieve dramatic noise reduction:

• Level 1 (Standard silenced): 75-80 dB(A) @ 7m – Basic sound-attenuated enclosure
• Level 2 (Super-silenced): 65-70 dB(A) @ 7m – Enhanced acoustic treatment, suitable for urban environments
• Level 3 (Hospital/residential grade): 55-62 dB(A) @ 7m – Maximum attenuation for noise-sensitive locations

The technology involves acoustic foam, mass-loaded vinyl barriers, resonance-damping panels, and carefully engineered airflow paths that maintain cooling while blocking sound. Cost scales with performance—a Level 3 enclosure might add 40-60% to the base generator cost.

I specified ultra-quiet enclosures for a downtown medical center that had generators 30 feet from patient windows. We achieved 58 dB(A) during full-load testing—quieter than normal conversation.

Weatherproof and Environmental Protection

Beyond noise, weatherproof generator housing protects against:

• Rain and snow: Sealed enclosures with weather-resistant louvers
• Extreme temperatures: Insulated enclosures with heating/cooling systems for arctic or desert environments
• Corrosive atmospheres: Marine-grade coatings and stainless steel components for coastal or chemical plant installations
• Seismic requirements: Reinforced mounting and tie-down systems for earthquake zones

For a coastal resort project in Florida, we specified marine-grade enclosures with stainless steel fasteners, epoxy-coated frames, and sealed electrical compartments. Standard steel enclosures would have corroded within 2-3 years in that salt-air environment.

Containerized Solutions

For maximum portability or temporary installations, containerized generators package everything—generator, fuel tank, switchgear, sometimes even transformers—inside a standard 20′ or 40′ ISO shipping container. Benefits include:

• Rapid deployment (crane it off a truck, connect utilities, start up)
• Built-in weather protection and security
• Relocatable /assets for changing site needs
• Simplified permitting (mobile equipment vs. permanent installation)

I’ve used containerized units for construction sites, emergency response deployments, and even a film production company that needed power in remote shooting locations.

Multiple custom enclosure configurations demonstrating soundproof housing options, weatherproof protection systems, and advanced acoustic treatment solutions designed for urban and noise-sensitive installation environments.

Fuel System and Runtime Modifications

How long can your generator run? The answer depends entirely on fuel system customization—one of the most practical areas for tailoring a generator to your needs.

Standard vs. Extended Fuel Tank Capacity

Most packaged generators come with base-mounted fuel tanks sized for 4-24 hours of runtime at rated load. But what if local codes require 48 hours? Or you’re in a hurricane zone where fuel delivery may be impossible for a week?

Extended fuel tank capacity options include:

• Sub-base tanks: Larger tanks integrated into the generator skid (24-72 hours typical)
• External day tanks: Separate tanks feeding the generator, refilled from bulk storage
• Bulk fuel systems: Underground or aboveground storage tanks (500-10,000 gallons) with automatic transfer pumps

For a rural hospital project, we designed a dual-tank system: 200-gallon sub-base tank for immediate response, plus a 2,000-gallon bulk tank with automatic transfer pump. This gave them 7+ days of continuous runtime at 70% load—well beyond the 96-hour NFPA requirement.

Fuel Type Flexibility

While most Cummins generators run on diesel #2, alternative fuel configurations include:

• Biodiesel compatibility: B5 is standard, but tanks and fuel systems can be upgraded for B20 or higher blends
• Dual-fuel systems: Natural gas primary with diesel pilot ignition, or vice versa
• Heavy fuel oil: For marine or utility-scale applications

I’ve specified natural gas/diesel dual-fuel systems for facilities with on-site gas service. They run on cheap natural gas during testing and normal outages, reserving diesel fuel for extended emergencies when gas service might also fail.

Fuel Management and Monitoring

Long-term fuel storage creates problems: algae growth, water contamination, fuel degradation. Custom fuel management systems address this:

• Fuel polishing: Circulation systems that filter and clean stored fuel
• Leak detection: Sensors and containment for environmental compliance
• Level monitoring: Remote fuel level monitoring via telemetry
• Automatic ordering: Systems that trigger fuel delivery when reserves drop below thresholds

One client’s generator never ran because the fuel had degraded over 5 years. We added a fuel polishing system with quarterly automatic circulation. Problem solved.

Meeting Industry Standards and Certifications

Customization isn’t just about features—it’s about compliance. Different applications face different regulatory requirements, and your generator must meet them.

UL 2200 Certification

UL 2200 certified generator sets are tested and listed for stationary standby power applications up to 600V. This standard covers:

• Electrical safety and construction
• Mechanical integrity
• Engine and alternator coordination
• Control and protective systems
• Enclosure requirements

For commercial buildings, UL 2200 listing is often required by the National Electrical Code (NEC) and local authorities. Custom generators intended for UL listing must be designed and built to these requirements from the start—you can’t “add” UL certification after the fact.

When I specify custom configurations, I always verify that customization won’t void UL listing. Adding a non-listed accessory or modifying listed components can compromise certification.

NFPA 110: Emergency Power Supply Systems (EPSS)

NFPA 110 compliance governs emergency power supply systems (EPSS) for critical facilities, particularly healthcare. Key requirements include:

• Level 1 (Healthcare): Equipment that, if failing, could result in loss of human life or serious injury. Requires 10-second start, full-load acceptance within 10 additional seconds.
• Level 2: Equipment that, if failing, could result in injury or equipment damage.
• Class specifications: Define runtime requirements (Class 2 = 2 hours, Class 24 = 24 hours, etc.)

Custom generator systems for hospitals must meet NFPA 110 acceptance testing, which includes sustained full-load runs and monthly/annual testing protocols. During generator commissioning process, we typically conduct a full “black building” test where utility power is disconnected and the entire facility runs on generator power for extended periods.

Environmental and Emissions Compliance

If your generator operates in an air quality management district with strict emissions regulations, you may need:

• Tier 4 Final emissions compliance for EPA non-emergency use
• California Air Resources Board (CARB) certification
• Particulate filters and selective catalytic reduction (SCR) systems
• Low-NOx combustion technology

These systems add significant cost ($15,000-$50,000+ depending on size) and complexity, but they’re non-negotiable in regulated areas. I’ve had projects in Southern California where we had no choice but to specify Tier 4 Final gensets with full aftertreatment systems.

Seismic Certification

In earthquake-prone regions (California, Pacific Northwest, Alaska), generators and switchgear must be seismically rated and mounted. This involves:

• IBC/CBC seismic certifications for equipment
• Engineered isolation pads or structural mounting
• Flexible fuel and exhaust connections
• Seismic restraint of external components

One hospital retrofit in San Francisco required complete seismic recertification of 30-year-old generators. We ended up replacing them with new Cummins units on seismically isolated pads because the upgrade cost approached replacement cost.

The Customization Process: What to Expect

Understanding the generator commissioning process timeline and workflow helps set realistic expectations and avoid costly delays.

Phase 1: Requirements Definition (2-4 weeks)

This is where many projects go wrong. Vague requirements lead to mismatched solutions. Work with your engineering team or consultant to document:

• Load analysis: Total kW/kVA, power factor, starting currents for motors
• Electrical specifications: Voltage, frequency, phase, grounding
• Runtime requirements: Fuel capacity, refueling logistics
• Environmental constraints: Noise limits, emissions regulations, space limitations
• Operational needs: Paralleling, ATS configuration, monitoring requirements
• Code compliance: UL, NFPA, EPA, local regulations

Provide this to potential suppliers—Cummins dealers, Tesla Power, Caterpillar distributors—for accurate proposals.

Phase 2: Engineering and Proposal (3-6 weeks)

Manufacturers will engineer a solution and provide proposals including:

• Technical specifications and single-line diagrams
• Equipment layout drawings
• Compliance certifications
• Pricing (equipment, installation support, commissioning)
• Lead time estimates

For complex customizations (medium voltage switchgear, multi-unit paralleling, integrated fuel systems), engineering may take longer. Don’t rush this phase—errors here cascade into expensive field changes.

Phase 3: Manufacturing (8-24 weeks)

Lead times vary dramatically based on customization extent:

• Standard configurations: 8-12 weeks
• Moderate customization (custom voltage, basic paralleling): 12-16 weeks
• Complex systems (custom switchgear, advanced controls, special enclosures): 16-24+ weeks

Supply chain disruptions can extend these timelines. I always add 20-30% buffer to manufacturer estimates for project scheduling.

For critical projects, consider factory acceptance testing (FAT) where you or your consultant witnesses testing at the factory before shipment. This catches issues early.

Phase 4: Installation and Commissioning (2-8 weeks)

Installation complexity depends on site conditions and system size. Industrial generator installation involves:

• Site preparation: Concrete pads, structural supports, seismic mounting
• Rigging and placement: Small units with forklifts, large units with cranes
• Utility connections: Fuel, exhaust, cooling, electrical
• Control integration: Wiring to switchgear, ATS, BMS

Generator load bank testing is critical during commissioning. This verifies:

• Rated output capacity
• Voltage and frequency stability under varying loads
• Control system operation
• Protective relay coordination
• Parallel operation and load sharing (for multi-unit systems)

For NFPA 110 facilities, formal acceptance testing with sustained runtime at varying load percentages is required. Budget several days for comprehensive commissioning.

Phase 5: Training and Documentation (1 week)

Don’t skip this. Your facilities team needs training on:

• Normal operation and testing procedures
• Alarm response protocols
• Basic troubleshooting
• When to call for service

Comprehensive documentation should include operation manuals, maintenance schedules, electrical drawings, control system programming, parts lists, and warranty information.

Cost Factors and Budget Planning

Let’s talk numbers. Custom generators aren’t cheap, but understanding cost drivers helps you spend wisely.

Base Generator Costs

As a rough baseline (2025 pricing):

• 50 kW diesel generator: $15,000-$25,000
• 150 kW: $35,000-$55,000
• 500 kW: $90,000-$140,000
• 1000 kW: $180,000-$280,000
• 2000 kW+: $350,000-$600,000+

These are base prices for standard configurations (open frame, basic controls, standard voltage/frequency).

Customization Cost Multipliers

Here’s what various customizations typically add:

Control Systems:

• Basic remote monitoring: +$2,000-$5,000
• PowerCommand advanced control: +$5,000-$15,000
• Full building integration (BMS, BACnet, etc.): +$10,000-$30,000

Enclosures:

• Weather enclosure: +15-25% of base cost
• Level 2 sound attenuation: +25-40%
• Level 3 hospital-grade quiet: +40-60%
• Containerized solution: +50-80%

Electrical Customization:

• Custom voltage (minor): +$3,000-$10,000
• Custom voltage (major rewinding): +15-20%
• Dual frequency capability: +20-30%
• Enhanced AVR: +$3,000-$8,000

Paralleling:

• 2-generator paralleling switchgear: +$40,000-$100,000
• 3-4 generator systems: +$80,000-$200,000
• Medium voltage switchgear: multiply by 2-3x

Fuel Systems:

• Extended sub-base tank (2x capacity): +$5,000-$15,000
• External bulk tank system: +$15,000-$50,000+
• Fuel polishing system: +$8,000-$20,000

Compliance:

• UL listing (if not standard): $5,000-$15,000
• Tier 4 Final emissions: +$15,000-$50,000
• Seismic certification and mounting: +$8,000-$25,000

Installation Costs

Equipment is only part of the budget. Industrial generator installation typically costs:

• Simple installations: 20-30% of equipment cost
• Moderate complexity: 30-50%
• Complex installations (rooftop, integrated paralleling, extensive electrical work): 50-100%+

That $100,000 generator might become a $150,000-$200,000 installed project.

Total Cost of Ownership

Don’t forget ongoing costs:

• Fuel storage and management: $1,000-$5,000/year
• Preventive maintenance: $2,000-$10,000/year depending on size and runtime
• Load bank testing (annual): $1,500-$5,000
• Remote monitoring service: $500-$2,000/year

A bespoke power solution for a critical facility might seem expensive upfront, but it’s insurance. Calculate the cost of downtime—for hospitals, data centers, or manufacturing, even one hour of outage can exceed the entire generator investment.

How Cummins Compares to Other Manufacturers

Cummins isn’t the only game in town. Here’s how they stack up against major competitors for custom diesel generator solutions.

Cummins Strengths

• Vertical integration: Cummins manufactures engines, alternators, controls, and transfer switches in-house, simplifying customization and warranty
• Global support network: Service and parts availability worldwide
• PowerCommand control ecosystem: Industry-leading digital control and monitoring platform
• Broad power range: 20 kW to 3+ MW with consistent technology platform
• Customization flexibility: Extensive options for voltage, frequency, paralleling, and packaging

Caterpillar (Cat)

Cat offers similar customization capabilities with some distinctions:

• Strengths: Extremely robust heavy-duty engines (think mining and marine applications); excellent at high-power (1 MW+) and low RPM continuous power applications
• Custom options: Comprehensive enclosure and fuel system options explicitly listed in product catalogs
• Cost: Generally 5-15% higher than comparable Cummins units
• Best for: Heavy industrial, mining, marine, and applications requiring maximum durability

Kohler

• Strengths: Strong in residential and light commercial markets; excellent acoustic enclosures
• Custom options: Good voltage/frequency flexibility; strong ATS integration
• Cost: Competitive with Cummins in smaller sizes (<500 kW)
• Best for: Commercial buildings, light industrial, applications prioritizing quiet operation

MTU (Rolls-Royce Power Systems)

• Strengths: Premium positioning with exceptional power density; leading technology in high-speed diesels
• Custom options: Advanced control systems; excellent paralleling solutions
• Cost: Premium pricing, 20-40% above Cummins/Cat
• Best for: Data center backup power, mission-critical facilities where performance justifies premium cost

Perkins (via packagers)

Perkins engines power many custom-built gensets through OEM partners:

• Strengths: Cost-effective solution; engines proven across global markets
• Customization: Depends on the packager; companies like Constant Power Solutions build Perkins-powered units “to exact customer specification”
• Cost: Often 10-20% below Cummins/Cat
• Best for: Budget-conscious projects, export markets, applications where brand name is less critical

My Recommendation Framework

• Mission-critical, no-compromise applications (Tier IV data centers, major hospitals): Cummins or MTU
• Heavy industrial, mining, extreme environments: Caterpillar
• Commercial buildings, noise-sensitive sites: Kohler or Cummins
• Value-focused, moderate requirements: Perkins-powered custom units or Cummins
• International projects needing local support: Cummins (best global network)

I’ve specified all of these brands over the years. For most applications requiring generator with automatic transfer switch and moderate customization, Cummins offers the best balance of capability, support, and cost.

Making the Right Choice for Your Application

After fifteen years specifying power systems, here’s what I’ve learned: the “right” generator isn’t the cheapest or the most feature-packed. It’s the one that matches your actual operational requirements without over-engineering or under-delivering.

Ask yourself these questions:

1. What’s the cost of downtime? If one hour offline costs more than the generator investment, prioritize reliability and redundancy over price.
2. What regulatory requirements apply? Healthcare, data centers, and life-safety applications face strict codes. Build compliance in from the start.
3. How will the site evolve? If you might add load in 5 years, oversizing or designing for future paralleling now is cheaper than retrofitting later.
4. What’s your maintenance capability? Sophisticated systems require sophisticated support. Be honest about your team’s technical depth.
5. Is this prime power or standby? Standby units run hours per year; prime power generator specifications must support thousands of hours annually. Different applications, different customization priorities.

The best projects I’ve worked on started with clear requirements, engaged experienced suppliers early, and made customization decisions based on operational value rather than feature lists. Whether you work with Tesla Power, a Cummins dealer, or another manufacturer, invest time in the engineering phase. Errors caught on paper cost hundreds; errors caught during commissioning cost thousands; and errors discovered during an actual outage are priceless—in the worst possible way.

Customization isn’t about building the perfect generator. It’s about building the right generator for your application, budget, and operational reality.

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Frequently Asked Questions

1. Can I customize an existing Cummins generator after purchase?

Limited modifications are possible post-purchase—adding remote monitoring, upgrading control panels, or installing sound attenuation—but fundamental changes (voltage, frequency, power output) typically require factory engineering. Major customizations like paralleling capability or fuel system changes are far more cost-effective when specified during initial purchase. I’ve seen clients spend 2-3x more trying to retrofit customizations versus building them in from the start.

That said, control system upgrades are usually straightforward. We’ve retrofitted older Cummins generators with modern digital controllers and remote monitoring, bringing 10-15 year old units into the current technology ecosystem for $8,000-$15,000 per unit.

2. How long does customization extend the delivery timeline?

Standard generators ship in 8-12 weeks. Moderate customizations (custom voltage, upgraded controls, special enclosures) add 4-8 weeks, putting delivery at 12-16 weeks. Complex customizations—paralleling switchgear solutions, medium voltage systems, or highly specialized configurations—can extend timelines to 20-28 weeks.

Supply chain issues can add further delays. For critical projects, I recommend building in 30-40% timeline buffer and maintaining communication with your supplier on component availability. Some clients specify “long-lead items” like switchgear early, even before finalizing other details, to compress overall project schedules.

3. Will customization void my Cummins warranty?

Not if done properly through authorized channels. Factory-engineered customizations through Cummins dealers or certified distributors like Tesla Power maintain full factory warranty. The risk comes from field modifications using non-approved components or making changes that weren’t engineered by the manufacturer.

Always verify that customizations are documented in your purchase order and that warranty coverage explicitly includes custom components. I’ve seen warranty disputes arise when “custom” work wasn’t properly documented. Get it in writing.

4. Can you parallel different brands of generators?

Technically possible but practically problematic. Different manufacturers use different control algorithms, voltage regulation methods, and communication protocols. Paralleling Cummins with Caterpillar, for example, requires custom integration work and sophisticated third-party paralleling controls—adding significant cost and complexity.

I’ve done it twice in my career, both times for legacy sites where replacing existing generators was impractical. Both projects cost 40-50% more than if we’d simply installed matched units. For new installations, always specify a matched set from one manufacturer.

5. What customization gives the best return on investment?

In my experience, generator remote monitoring systems deliver the highest ROI. For 10-15% added cost on controls, you get:

• 40-60% reduction in emergency service calls (catching issues before failure)
• Proactive maintenance based on actual runtime data rather than calendar schedules
• Real-time visibility during outages without site visits
• Historical data for warranty claims and performance analysis

The second-best ROI customization is proper fuel system sizing. Running out of fuel during an extended outage is catastrophic—and completely avoidable. Spending $10,000-$30,000 on extended fuel tank capacity to achieve code-required runtime is money extremely well spent.

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References

• Cummins Power Generation – Generator Set Controls
• UL 2200 Standard for Stationary Engine Generator Assemblies
• NFPA 110: Emergency and Standby Power Systems
• EPA Diesel Engine Regulations and Tier Standards
• Tesla Power Generator Solutions
• Caterpillar Electric Power – Generator Set Enclosures
• National Electrical Code (NEC) Article 700 – Emergency Systems
• ISO 8528 Standards for Reciprocating Internal Combustion Engine Driven Alternating Current Generator Sets