Compact Transformer

The Evenson Power Compact Transformer, often referred to as a compact or packaged substation, is a fully integrated power-distribution unit that combines several discrete pieces of substation equipment into a single, factory-assembled enclosure. Rather than specifying, procuring, and field-wiring a separate transformer, medium-voltage switchgear, and low-voltage distribution board, our customers receive one coordinated assembly that has been engineered, built, and tested as a complete system. This dramatically shortens installation time, reduces the on-site labor and civil works required, and minimizes the chance of integration errors during commissioning.

Evenson Power designs every compact unit around real-world deployment constraints: limited footprint, fast energization schedules, and demanding service environments. Whether the unit feeds a commercial development, an industrial plant, or a renewable generation site, it arrives ready to connect, energize, and run.

A compact transformer is a prefabricated electrical substation in which the incoming medium-voltage circuit, the step-down power transformer, and the outgoing low-voltage distribution equipment are housed together inside a single protective shell. The high-voltage section typically includes a load-break switch, disconnects, and protective fusing or a circuit breaker; the core of the unit is the power transformer itself; and the low-voltage section provides metering, protection, and feeder distribution.

Because the assembly is built and verified in a controlled factory setting, a compact transformer offers far more predictable performance and quality than equivalent equipment assembled in the field. It is the ideal solution where conventional open-air or building-based substations are impractical due to space, aesthetics, or schedule.

The internal power transformer can be supplied as an oil-immersed or cast-resin dry-type unit depending on the application and fire-safety requirements. High-voltage and low-voltage busbars, lightning arrestors, control wiring, and protection systems are all pre-routed and labeled at the factory. The result is a tidy, serviceable, and electrically coordinated package.

• Heavy-gauge, powder-coated steel or stainless enclosure with IP-rated weather protection
• Segregated HV, transformer, and LV compartments for safe operation
• Integrated load-break switch, disconnects, fusing, and lightning arrestors
• Factory-routed HV and LV busbars with full control and protection wiring
• Forced or natural ventilation sized to the internal heat load

Evenson Power compact transformers are offered across a broad capacity band to suit everything from a single building to a large industrial campus or utility feeder. Standard units cover roughly 300 kVA through tens of thousands of kVA, with custom engineering available for larger ratings. Medium-voltage classes are supported up to 35 kV and below for typical packaged-substation duty, while our wider transformer program extends to high- and extra-high-voltage classes for specialized applications.

Each unit is configured with the primary and secondary voltages, vector group, and tapping range required by the site, ensuring the delivered low-voltage output matches local distribution needs precisely.

• Single integrated package reduces footprint and civil works
• Factory-assembled and tested for predictable, repeatable quality
• Fast on-site installation and energization
• Sealed, weatherproof enclosure suited to outdoor placement
• Coordinated protection across HV and LV sections
• Available with no-load or on-load tap changing for voltage regulation
• Configurable oil-immersed or dry-type internal transformer

Compact transformers are deployed wherever reliable power must be delivered in a constrained space or on an aggressive schedule. They are a natural fit for commercial real estate, mixed-use developments, data centers, and campuses, as well as industrial plants where process loads demand a dependable medium-to-low-voltage step-down close to the point of use.

They also excel in renewable and infrastructure projects. Solar farms, wind sites, and battery storage installations frequently use compact or box-type units as collection and step-up points, while transportation, water-treatment, and municipal infrastructure rely on them for distributed, low-maintenance power.

• Commercial buildings, mixed-use developments, and data centers
• Industrial and manufacturing plants
• Solar, wind, and battery energy-storage collection points
• Municipal, water, and transportation infrastructure

Every Evenson Power compact transformer is manufactured and verified against internationally recognized standards covering transformers, switchgear, and assembled substations. Units are routine-tested for ratio, winding resistance, insulation resistance, dielectric withstand, and functional operation of the switching and protection devices before they leave the factory. Type and special tests are available on request for projects with elevated qualification requirements.

Compliance with IEC, IEEE/ANSI, UL, CE, and related standards, together with documented factory acceptance testing, gives specifiers confidence that the delivered unit will perform exactly as rated on day one.

Because the unit is shipped as a complete assembly, installation typically reduces to placing the enclosure on a prepared foundation or pad, landing the incoming medium-voltage cables, connecting the low-voltage feeders, and bonding the ground system. Commissioning checks confirm switching, protection, and tapping before energization.

In service, compact transformers require only modest maintenance. Evenson Power recommends a documented inspection at least annually, with more frequent checks in hot, dusty, coastal, or otherwise harsh environments. Routine activities include visual inspection, thermographic scanning, checking oil level and quality where applicable, verifying ventilation, and confirming the integrity of seals, connections, and protective devices.

• Place on prepared pad, land HV and LV cables, bond to ground
• Commission switching, protection, and tap settings before energizing
• Inspect at minimum annually; more often in harsh environments
• Thermographic scans, oil checks, and seal/connection verification

Evenson Power builds compact transformers to a single standard: dependable American-grade power equipment that installs fast and runs for decades. Each unit is engineered to the specific voltages, capacities, and environmental conditions of the project, factory-tested as a complete system, and backed by responsive technical support. When you specify Evenson Power, you get an integrated substation solution that saves space, saves schedule, and delivers reliable power you can build on. Backed by Evenson Power engineering support, every compact substation is delivered ready for rapid, dependable deployment on the network.