500 kVA Transformers

In Stock Since 1973

500 kVA Dry-Type Transformers – Built for Heavy Industrial & Data Centers.

Engineered for large manufacturing floors, hospital complexes, and mission-critical data centers. Handles substantial three-phase loads with 480V primary and 208Y/120V secondary standard. K-Factor rated options available for harmonic-rich environments.

✔ 500 kVA units tested for full-load heat run before shipment    ✔ K-13 and K-20 ratings for VFD and server loads    ✔ Reconditioned options save 40–60% vs factory lead times

Request a Quote Contact Support Used & Reconditioned

500 kVA Transformer Specifications

Specifications vary by manufacturer, voltage class, winding material, temperature rise, and application. The values below are typical selection parameters rather than universal nameplate values.

How Many Amps Can a 500 kVA Transformer Handle?

A 500 kVA transformer does not have one fixed amperage rating. Full-load current depends on secondary voltage and phase. Use the transformer nameplate and project calculations for final equipment, conductor, and overcurrent-protection selection.

Single-phase: Amps = (500 x 1,000) / Volts

Three-phase: Amps = (500 x 1,000) / (1.732 x volts)

Common examples: approximately 601A at 480V three-phase, 1,388A at 208V three-phase, and 1,042A at 480V single-phase.

500 kVA Transformer Full-Load Amps Reference Table

Important Note: Three-phase calculations use line-to-line voltage. In a 480Y/277V system, use 480V to calculate total three-phase transformer current; 277V is the line-to-neutral voltage for connected branch loads.

Overcurrent protection, conductor ampacity, grounding and bonding, ventilation, working clearances, and installation methods must comply with the adopted electrical code, the manufacturer’s instructions, and the authority having jurisdiction.

500 kVA Transformer Load Capacity

A 500 kVA transformer can supply up to 500,000 VA of apparent power under its rated nameplate conditions. The real-power capacity available in kilowatts depends on the load power factor:

kW = kVA x Power Factor

Improving power factor does not increase the transformer’s 500 kVA rating. It reduces the kVA required for a given kW load, allowing the available transformer capacity to be used more effectively.

Transformer sizing should account for:

1. Maximum demand and load diversity, not connected nameplate load alone

2. Motor starting, inrush current, cycling loads, and voltage-drop limits

3. VFDs, UPS systems, rectifiers, EV chargers, and other nonlinear or harmonic-producing loads

4. Ambient temperature, elevation, ventilation, enclosure, and temperature-rise limitations

5. Continuous loading, redundancy requirements, and planned facility expansion

500 kVA Transformer Types and Voltage Configurations

500 kVA units are commonly specified as general-purpose distribution transformers, K-factor-rated or harmonic-mitigating transformers for nonlinear loads, autotransformers where electrical isolation is not required, and low- or medium-voltage dry-type transformers.

Common 500 kVA Three-Phase Configurations

Select Single-Phase Configurations

Most 500 kVA facility-distribution transformers are three-phase. Single-phase 500 kVA units are generally select or custom products for large dedicated loads, utility applications, industrial processes, OEM systems, or medium-voltage distribution.

Step-Up vs. Step-Down

A 500 kVA step-down transformer lowers voltage, commonly from 480V to 208Y/120V. A 500 kVA step-up transformer raises voltage, such as 208V to 480Y/277V, to supply higher-voltage equipment from a lower-voltage source. Specify the exact primary and secondary voltages, phase, winding connection, taps, neutral and grounding requirements, and whether electrical isolation is required.

500 kVA Transformer Weight, Dimensions, and Enclosures

A 500 kVA dry-type transformer typically weighs several thousand pounds, but there is no universal weight or footprint. Low-voltage aluminum-wound units are generally lighter than comparable copper-wound units, while lower-temperature-rise, medium-voltage, cast-resin, and heavy-duty outdoor designs may be larger and heavier.

Representative low-voltage models may be about 48-56 inches wide, 38-45 inches deep, and 71-76 inches high, with weights from approximately 2,900 pounds upward. Use the certified manufacturer drawing for rigging, floor loading, cable entry, ventilation, and working-clearance planning.

Common enclosure options include:

1. NEMA Type 1: Indoor electrical rooms and controlled environments

2. NEMA Type 2: Indoor locations requiring additional protection from limited falling moisture

3. NEMA Type 3R: Outdoor installations exposed to rain, sleet, and weather

4. Specialty enclosures: Type 4/4X, Type 12, corrosion-resistant, seismic, or enhanced outdoor designs when available

Applications of 500 kVA Transformers

1. Industrial Manufacturing: Plant distribution, motor control centers, production line power.

2. Data Centers & Critical Infrastructure: UPS systems and mission-critical distribution.

3. Healthcare Campuses: Hospital distribution and medical equipment infrastructure.

4. Renewable Energy: Solar and battery storage interconnection.

5. Water & Wastewater Facilities: Pump station and treatment plant power.

6. Commercial High-Rises: Main distribution and tenant power systems.

7. Machine Control & OEM Equipment: Single-phase 500 kVA control transformers supply large control panels, industrial process equipment, and high-capacity pool/spa heating systems.

8. Commercial Buildings: Main distribution, tenant power, HVAC, lighting, and service upgrades

How to Select the Right 500 kVA Transformer

1. Confirm voltage, phase, and frequency: Verify source voltage, required load voltage, phase, winding connection, system frequency, neutral requirements, and grounding method.

2. Evaluate the load: Review maximum demand, load diversity, motor starting, inrush, nonlinear loads, power factor, duty cycle, and expected expansion.

3. Select the correct transformer type: Use general-purpose designs for conventional distribution, K-factor or harmonic-mitigating designs for nonlinear loads, autotransformers only where isolation is unnecessary, and medium-voltage units for the applicable voltage class.

4. Review impedance and system coordination: Confirm available fault current, transformer impedance, interrupting ratings, selective coordination, voltage drop, and protective-device requirements.

5. Choose construction and enclosure: Specify winding material, temperature rise, insulation system, taps, shielding if required, enclosure, and environmental options.

6. Verify installation and replacement requirements: Check certified dimensions, weight, ventilation, cable access, rigging and clearances. For replacements, match complete nameplate data and terminal arrangement.

500 kVA Transformer Installation Considerations

1. Structural support: Confirm that the floor, pad, mezzanine, or mounting surface can support the transformer and installation loads.

2. Ventilation and heat dissipation: Maintain manufacturer-required airflow and clearances, and account for room temperature, elevation, and enclosure heat.

3. Cable and termination space: Plan for large or parallel conductors, conduit entry, cable bending radius, neutral conductors, and accessible terminations.

4. Fault-current and protection studies: Coordinate transformer impedance, available fault current, overcurrent protection, equipment ratings, and grounding.

5. Noise and location: Evaluate audible sound, vibration isolation, proximity to occupied areas, and environmental exposure.

6. Maintenance and replacement access: Preserve working space and a practical route for inspection, testing, rigging, and future replacement.

Frequently Asked Questions

Q1. What is the typical impedance of a 500 kVA dry-type transformer?

Many 500 kVA dry-type distribution transformers are approximately 5% to 6.5% impedance, but the exact value varies. Use the nameplate or approved submittal value for fault-current and coordination studies.

Q2. How many amps is a 500 kVA transformer at 480V three-phase?

Approximately 601A at full load, calculated as 500,000 divided by 1.732 x 480. The nameplate and project design govern final sizing.

Q3. How many amps is a 500 kVA transformer at 208V three-phase?

Approximately 1,388A at full load. This high current often requires substantial bus or parallel-conductor capacity.

Q4. How many kilowatts can a 500 kVA transformer supply?

Approximately 500 kW at unity power factor, 450 kW at 0.90 power factor, or 400 kW at 0.80 power factor, subject to nameplate and operating conditions.

Q5. How much does a 500 kVA dry-type transformer weigh?

Most units weigh several thousand pounds. Exact weight depends on voltage class, winding material, temperature rise, enclosure, and construction. Use the certified drawing for rigging and structural planning.

Q6. Can a 500 kVA dry-type transformer be installed outdoors?

Yes, when the transformer is supplied with an enclosure and construction suitable for the environment, commonly NEMA Type 3R or another manufacturer-approved outdoor design.

Q7. What is the difference between a 500 kVA step-up and step-down transformer?

A step-up transformer increases voltage from source to load, while a step-down transformer reduces voltage. The 500 kVA rating describes apparent-power capacity, not the direction of voltage conversion.

Q8. Are 500 kVA transformers available in single-phase designs?

Yes, but most facility-distribution units at this rating are three-phase. Single-phase 500 kVA transformers are generally select or custom units for large dedicated loads, utility systems, industrial processes, OEM equipment, or medium-voltage applications.