15 kVA Transformers

A 15 kVA dry type transformer is one of the most widely specified sizes in commercial and light industrial electrical work, used for stepping down 480V building service to 208Y/120V for panel distribution, feeding lighting and HVAC control circuits, powering machine tool feeders, and supporting branch distribution in tenant fit-outs, institutional facilities, and construction projects where a compact, reliable voltage conversion solution is required.

At Bruce Electric Equipment Corp., we supply new, used and reconditioned 15 kVA transformers in single phase and three phase configurations. Since 1973, Bruce Electric has specialized in dry type transformers and electrical distribution equipment from leading manufacturers including Acme Electric, Hammond Power Solutions (HPS), Eaton and more. Our team can help source the right unit for your application. We offer fast nationwide shipping across the United States along with technical support.

 

Technical Specifications

Parameter Available Options
Phase Single-Phase, Three-Phase
Frequency 60 Hz (standard); 50/60 Hz (export models); 50 Hz
Primary Voltage 120V – 4160V (model-dependent)
Winding Material Aluminium or Copper
Temperature Rise 80°C, 115°C, 130°C, 135°C, 150°C, 180°C
Enclosure NEMA 1, NEMA 2, NEMA 3R, NEMA 3R Encapsulated, NEMA 3R Heavy Duty, NEMA 3R Stainless Steel, Encapsulated
Insulation Class Class H (220°C) standard for 150°C rise units
Taps Varies by model; 2–6 taps at 2.5% FCAN/FCBN typical

 

Available 15 kVA Transformers Voltage Configurations

Bruce Electric’s 15 kVA inventory covers a broader range of voltage configurations than most distributors carry across all kVA ratings combined. The following are confirmed from actual inventory.

Three-Phase Configurations

Primary Voltage Secondary Voltage Application
480V 208Y/120V 192 SKUs – North American commercial step-down; feeds 208V/120V tenant and floor panels
208V 208Y/120V Step-down where 208V is the building service; maintains 208Y/120V distribution
600V 208Y/120V Canadian commercial and industrial facilities; most common Canadian config
480V 480Y/277V Establishes neutral on delta 480V source; 277V for commercial lighting ballasts and LED drivers
208V 480Y/277V Step-up from 208V service to feed 480V equipment
240V 208Y/120V Step-down from lower-voltage service; commercial and light industrial
600V 480Y/277V Canadian facilities requiring 277V lighting distribution
480V 240V Delta secondary applications; ungrounded 240V three-phase loads
480V 240/120V Delta-secondary with center-tap for 120V single-phase loads
480V delta 208Y/120V Delta primary to wye secondary; industrial delta-source facilities
240V 480Y/277V Step-up from 240V service to 480Y/277V for mixed lighting/equipment feeds
480V 400Y/231V International equipment requiring IEC-standard voltage
380V 208Y/120V European/international primary to North American secondary
415V 208Y/120V UK and international primary to North American secondary
440V 220Y/127V Export and international three-phase applications
460V 230Y/133V International step-down, export OEM equipment
208V 480V Step-up for 480V equipment from 208V service
208V 400Y/231V International secondary from North American primary
2400V 208Y/120V, 480Y/277V, 600Y Medium voltage distribution to LV utilization
4160V 208Y/120V, 480Y/277V, 600Y MV utility step-down at point of load

 

Single-Phase Configurations

Primary Voltage Secondary Voltage Application
240 × 480V 120/240V Dual-primary step-down; most common single-phase config (25 SKUs)
600V 120/240V Canadian single-phase service to 120/240V
208V 120/240V Single-phase step-down from 208V panel
480V 120/240V Single-phase step-down from 480V service
277V 120/240V Step-down from 277V lighting circuit to 120V
120/208/240/277V 120/240V Multi-tap primary; maximum installation flexibility
190/200/208/220V 120/240V International multi-tap, export applications
2400V 120/240V Medium voltage single-phase to 120/240V
4160V 120/240V MV single-phase step-down

 

How Many Amps Can a 15 kVA Transformer Handle?

Full-load amperage is determined by the secondary voltage and phase configuration. Use these formulas:

Single-phase: FLA = 15,000 ÷ Secondary Voltage

Three-phase: FLA = 15,000 ÷ (Secondary Voltage × 1.732)

 

15 kVA Transformer Amperage Reference Table:

Configuration Secondary Voltage Full Load Amps (FLA)
Single Phase 120V 125.0 A
Single Phase 240V 62.5 A
Single Phase 277V 54.2 A
Three Phase 208Y/120V 41.6 A
Three Phase 240V 36.1 A
Three Phase 480V 18.0 A
Three Phase 480Y/277V 18.0 A

A 15 kVA transformer provides adequate load capacity for small sub-panels, lighting circuits, HVAC controls, machine tool feeders, and commercial branch distribution. For larger load requirements, see our 30 kVA, 25 kVA, or 45 kVA transformer categories.

 

15 kVA Step-Down, Step-Up, and Specialty Dry Type Transformers

15 kVA Step Up Transformers

A 15 kVA step up transformer raises a lower incoming voltage to a higher output voltage. The most common application is feeding 480V-rated equipment from a 208V or 240V service, a frequent requirement when installing imported machinery, upgrading control panels, or reverse-feeding distribution in facility renovations. All step-up units in our inventory are three phase dry type, available from GE, Acme Electric, Federal Pacific, EGS/SolaHD, Jefferson Electric, and Hammond Power Solutions.

 

15 kVA Step-Up Configurations Available:

Primary Voltage Secondary Voltage Phase Example Unit
208V 480V Three Phase GE 9T83B3031
208V 480Y/277V Three Phase Acme Electric T3793671S
208V 480Y/277V Three Phase Federal Pacific T204H15E
208V 480Y/277V Three Phase EGS/SolaHD ET84H15
208V 277V / 480Y Three Phase Hammond Power Solutions
240V 480Y/277V Three Phase Acme Electric T3796931S
240V 480Y/277V Three Phase EGS/SolaHD ET85H15S
240V 277V / 480Y Three Phase Hammond Power Solutions

15 kVA Step Down Transformers

A 15 kVA step down transformer reduces a higher primary voltage to a lower, usable secondary voltage. This is the most common transformer type in commercial and industrial electrical work, stepping 480V three-phase building distribution down to 208Y/120V for panels, outlets, and equipment, or 480V single phase down to 120/240V for lighting and branch circuits. We also carry 600V primary configurations for Canadian facilities and industrial plants running 600V distribution.

 

15 kVA Step-Down Configurations Available:

Primary Voltage Secondary Voltage Phase Example Unit
480V 208Y/120V Three Phase GE 9T10C1001
480V 208Y/120V Three Phase Acme Electric TPC3533113S
480V 208Y/120V Three Phase EGS/SolaHD 3H13T2H15S
480V 240D/120CT Three Phase Jefferson Electric 423-9167-000
480V 240Y/139V Three Phase GE (multiple)
480V 380Y/219V Three Phase GE (multiple)
480V 416Y/240V Three Phase MGM
480V 120/240V Single Phase Federal Pacific S2T15E
480V 240/120V Single Phase Acme Electric PT061150015LS
277/480V 208/277V Single Phase Acme Electric GP1215000S
240 × 480V 120/240V Single Phase Acme Electric T2535173S
277V 120/240V Single Phase Acme Electric T2536771S
600V 208Y/120V Three Phase Acme Electric T3793331S
600V 208Y/120V Three Phase Hammond Power Solutions P015PBKF
600V 240/120V Three Phase GE 9T83B3614
600V 416Y/240V Three Phase MGM
600V 380Y/219V Three Phase MGM
600V 120/240V Single Phase Acme Electric T2536171S

 

15 kVA Specialty Dry Type Transformers

All 15 kVA transformers we stock are dry type units that use air cooling instead of oil, making them ideal for indoor commercial, healthcare, educational, and data center applications. Available options include general purpose, encapsulated, K-factor rated (K4, K13, K20), buck-boost, and isolation transformers for applications ranging from harmonic mitigation and voltage correction to noise reduction and electrical isolation. Contact our team for assistance with specific enclosure, temperature rise, or configuration requirements.

Enclosure Selection: NEMA 1 or NEMA 2 for clean, dry indoor locations. NEMA 3R for outdoor or damp environments. NEMA 3R Stainless Steel for wash-down, food processing, or coastal chemical exposure. For more information, read the blog: NEMA Enclosure Ratings Explained: Guide to NEMA Types, Chart & Applications.

 

Applications: Where Is a 15 kVA Transformer Used?

1. Commercial office and retail buildings: Commercial office and retail buildings commonly use 15 kVA transformers for branch panels, lighting circuits, and tenant power distribution.

2. Lighting distribution. 15 kVA units can support commercial lighting loads, control circuits, and voltage conversion for facility lighting systems.

3. Light manufacturing and assembly. These transformers are used for machine tool feeders, small production equipment, control panels, and localized power distribution.

4. Data centers and server rooms: Data centers and server rooms use dry type transformers for reliable power distribution in IT, UPS, and support infrastructure.

5. Healthcare and institutional facilities: Healthcare and institutional facilities use 15 kVA transformers for dependable electrical distribution in critical and facility-support applications.

6. International and export OEM. Multi-voltage and export configurations help match North American equipment to international electrical systems.

7. Outdoor and industrial installations. NEMA 3R and encapsulated units are suitable where damp-location or outdoor protection is required.

8. Renovation and replacement. 15 kVA transformers are commonly used for replacing failed units, upgrading panels, and supporting tenant improvement projects.

 

Installation Considerations for 15 kVA Transformers

Before installation, verify the transformer nameplate, voltage, phase, enclosure rating, load requirements, and applicable NEC requirements. Installation should be completed by a qualified electrical professional.

1. Ventilation. Maintain manufacturer-required airflow clearance to prevent heat buildup.

2. Overcurrent protection. Size primary and secondary protection based on NEC Article 450, nameplate data, voltage, and conductor sizing.

3. Conductor sizing. Select conductors based on full-load amps, insulation rating, terminal temperature limits, and installation conditions.

4. Grounding and bonding. Confirm grounding requirements, especially for separately derived secondary systems.

5. Enclosure rating. Use NEMA 1 or NEMA 2 for suitable indoor locations; use NEMA 3R or encapsulated options where outdoor or damp-location protection is required.

6. Taps. Verify available tap settings before energizing the transformer.

7. Mounting and access. Allow space for wiring, inspection, ventilation, maintenance, and future replacement.

8. Weight and handling. Confirm dimensions, shipping weight, and lifting requirements before delivery.

 

Why Electrical Professionals Choose Bruce Electric for 15 kVA Transformers

Bruce Electric Equipment Corp. has been a trusted source for dry type transformers and electrical distribution equipment since 1973. Contractors, facility managers, MRO buyers, and OEMs across the United States rely on us because we carry the inventory depth, product knowledge, and service infrastructure that generic electrical distributors don’t. When you need the right 15 kVA transformer correct voltage, phase, enclosure, and winding without chasing multiple suppliers, Bruce Electric is where professionals come first.

1. New, surplus & reconditioned. Every refurbished unit is inspected, tested, and covered by our BEE warranty (up to 2 years).

2. Fast shipping. Most units ship same-day or next-day, nationwide.

3. Spec support. Our team matches voltages, enclosures, and replacement units on request.

4. Hard-to-find units. Not listed online? Contact us. We source non-catalogue and discontinued configurations regularly.

 

FAQs

Q1. What is a 15 kVA transformer load capacity?

A 15 kVA transformer has a 15,000 VA apparent power rating. Real usable kW depends on power factor. At 0.9 power factor, 15 kVA equals approximately 13.5 kW.

Q2. How many amps is a 15 kVA transformer at 480V?

A 15 kVA transformer at 480V single-phase supplies approximately 31.25 amps. At 480V three-phase, it supplies approximately 18.04 amps.

Q3. Can a 15 kVA transformer be used outdoors?

Yes, if the transformer has a suitable outdoor-rated enclosure, such as NEMA 3R or another appropriate enclosure rating for the installation environment. Always confirm the enclosure rating before outdoor installation.

 

Browse Related Transformer Categories

1. 10 kVA Transformers

2. 25 kVA Transformers

3. 30 kVA Transformers

4. 45 kVA Transformers

Technical Reading

1. Dry Type Transformer Testing & Troubleshooting Guide

2. Dry Type Transformer Cooling: Natural Air vs. Forced Air

3. Transformer Losses & Efficiency Guide