Paralleling switchgear lineup with multiple generators
Paralleling Switchgear · Vendor-Neutral · Fort Myers, FL

Paralleling switchgear,Engineered to your plant, not pulled from a catalog

Multi-generator paralleling, utility synchronization, closed-transition transfer, and load share for healthcare, data centers, utilities, and prime-power plants. New build or zero-downtime retrofit. Works with any generator OEM.

Generators in parallel
2 to 8+
Sync and protection
Utility-grade
480V through 15kV
LV & MV
Downtime retrofits
Zero

Why Our Paralleling Is Different

Engineered to the plant, not configured from a menu.

Engineered, not configured

Every paralleling switchgear lineup we build is engineered to the specific generator plant: number of sources, kW ratings, governor types, voltage class, utility interconnection, and operating modes. Not assembled from a configurator.

Vendor-neutral generator support

We integrate with Caterpillar, Cummins, MTU, Kohler, Generac, Mitsubishi, and others. Open communication protocols throughout. No tie to a single generator OEM.

Full sequence of operations

Dead-bus closing, synchronization, real and reactive load sharing, governor and AVR coordination, load shedding under fault, orderly transfer between utility and generators. Written, simulated, and commissioned.

ControlCom Connect ready

Run hours, breaker operation counts, sync events, thermal trends, and anomaly detection on every generator and every breaker the day the gear is energized.

Operating Modes We Engineer For

Standby, prime, peak shaving, or base load.

Emergency standby

Utility loss triggers dead-bus close on the first generator, synchronization of the rest, and orderly retransfer to utility on restoration. Compliant with NFPA 110 for essential electrical systems.

Prime power

Generators carry the facility as the primary source. Utility is the backup or absent entirely. Continuous duty, load share, and lead-lag rotation for engine hour management.

Peak shaving and demand limiting

Generators run during utility peak windows to keep demand below the tariff threshold. Closed-transition transfer eliminates the blink. Pays back through avoided demand charges and ratchet penalties.

Base load and curtailment

Generators carry a defined portion of the load continuously, with the balance from utility. Includes utility curtailment programs where the facility is paid to shed or supply on signal.

Sequence of Operations

What actually happens when the lights blink.

Six stages, every one documented, simulated, and commissioned. This is the substance behind the words "paralleling switchgear."

Source qualification

Stage 1

Each generator monitored for voltage, frequency, and phase rotation before it is allowed to close to the bus. Faulted or out-of-tolerance sources are blocked at the protection layer.

Dead-bus closing

Stage 2

First generator to qualify on a dead bus closes immediately. Subsequent generators synchronize to the live bus. Anti-deadbus race logic prevents simultaneous closing.

Sync check and close

Stage 3

Slip frequency, slip phase, and voltage match all within tolerance for the configured close window. Sync check relay supervises every paralleling breaker close, with hardwired backup to the controller.

Load share and AVR coordination

Stage 4

Real load shared by governor droop or isochronous load share. Reactive load shared by AVR cross-current compensation or VAr/PF control. Adjustable bias for plant-specific tuning.

Load shed and ride-through

Stage 5

Fast bus protection and underfrequency-based load shed protect the plant against fault or sudden load loss. Ride-through configured per generator and per priority load tier.

Transfer and retransfer

Stage 6

Open or closed transition between utility and generators per the operating mode. Closed transition keeps the load energized during transfer. All transitions logged and time-stamped to the sequence-of-events recorder.

Two Paths

Build new, or modernize what you already have.

Build new

Custom-engineered paralleling switchgear lineup for greenfield plants or full replacement. Engineered around your generators, your utility interconnection, and your operating modes.

  • PE-stamped engineering: single-line, schematics, sequence of operations, protection settings, layout
  • Factory build with witnessed acceptance test on request, including paralleling simulation
  • Field install and commissioning, hot or cold cutover
  • Operator training, runbook, and as-built documentation handoff at energization

Retrofit existing

Modernize legacy paralleling switchgear and controls without replacing the structural lineup. Common path for facilities with 1990s-era gear that runs on obsolete or unsupported controllers.

  • Replace obsolete paralleling controllers, sync check relays, and metering with modern equivalents
  • Add closed-transition transfer, fast bus protection, and arc flash mitigation where retrofit-compatible
  • IEEE C37.59 design verification for the retrofitted configuration
  • Phased, zero-downtime execution with documented bypass plan and revert path

Specifications

The technical envelope.

System voltage
208V, 480V, 600V (low voltage); 4.16kV, 13.8kV, up to 15kV class (medium voltage)
Generators in parallel
Typically 2 to 8, larger configurations engineered on request
Standards (LV)
UL 1558 metal-enclosed LV power circuit breaker switchgear, UL 1066 breakers
Standards (MV)
IEEE C37.20.2 metal-clad switchgear, IEEE C37.04 / C37.09 breakers
Controls platform
PLC-based (Allen-Bradley, Siemens, Schneider) with operator HMI and SCADA integration
Sync supervision
Sync check relay hardwired in series with controller logic; dual-supervision close
Protection
Microprocessor relays with generator differential, reverse power, loss of field, frequency, voltage, and bus protection
Load share method
Isochronous load share (CAN bus or analog) or droop with bias; configurable per application
Transfer modes
Open transition, closed transition (paralleled), or soft load / soft unload to utility
Communications
Modbus TCP, DNP3, IEC 61850, BACnet, OPC UA; generator OEM protocols (Modbus to most ECUs)
Arc resistance
Type 2B available where the application calls for it (IEEE C37.20.7)

How We Compare

Where we fit alongside the major paralleling vendors.

We are not trying to be the biggest. We are trying to be the right call for facilities that want serious engineering, no vendor lock-in, and the option to retrofit.

vs Caterpillar / Cat Paralleling Switchgear

Cat is a generator OEM that sells paralleling switchgear largely as a captive accessory. We are an independent power systems engineering firm: we integrate with Cat generators, Cummins, MTU, Kohler, Generac, and others through open protocols, with no tie to one OEM's service contract.

vs ASCO / Russelectric / Kohler Paralleling

These are good products. The difference is delivery model and lock-in. We deliver a vendor-neutral, fully documented system that your team, any qualified third party, or we can service. No proprietary platform required to make changes.

vs Eaton / ABB / Schneider Paralleling

The major OEMs build excellent gear, on long lead times, configured from a catalog. We engineer to the specific plant on shorter timelines, with retrofit as a real option, and without locking the facility into one vendor's ecosystem.

How It Works

From plant review to commissioning in four steps.

  1. 01

    Plant review

    On-site walkdown for retrofits, or generator specs, utility interconnection, and operating-mode review for new construction. By a power systems engineer.

  2. 02

    Engineering package

    PE-stamped single-line, sequence of operations, protection settings, control logic, communications architecture, and witness-test plan.

  3. 03

    Factory build or in-place retrofit

    Listed assembly built and tested in our shop, or phased zero-downtime retrofit on the energized plant. Documented sequence the whole way.

  4. 04

    Commission, train, monitor

    Full functional and paralleling tests, operator training, runbook handoff, and ControlCom Connect activation at energization.

In the Field

What a finished paralleling switchgear plant looks like.

Who It Is For

Built for plants that have to stay up.

  • Healthcare

    Hospital essential electrical systems with multi-generator paralleling, life-safety branch isolation, and NFPA 110 compliance.

  • Data Centers

    Tier III and IV plants with N+1 or 2N generator schemes, closed-transition transfer, and concurrent maintainability through the paralleling bus.

  • Utilities & Generation

    Base-load operation, peak shaving, curtailment programs, and prime-power generation. Multi-engine plants up to 8+ generators.

  • Water & Wastewater

    Continuous-process facilities with prime-power or standby paralleling plants. EPA compliance protected through the work.

Common Questions

Answers from our engineering team.

Talk to a Power Systems Engineer

Tell us about the plant: generator count and ratings, voltage class, utility interconnection, and operating modes. We will get back within 24 hours.

  • Reviewed by a power systems engineer, not a salesperson
  • New build or zero-downtime retrofit, whichever fits
  • Works with any generator OEM: Cat, Cummins, MTU, Kohler, Generac, others
  • Vendor-neutral, fully documented, ControlCom Connect ready

Tell us about your paralleling plant

Number of generators, kW ratings, voltage, utility interconnection, and the operating modes you need.