01Where a 5000 kVA Transformer Fits
A 5000 kVA transformer is a 5 MVA unit and a preferred continuous three-phase rating in the verified IEEE rating series provided for this page. Three-phase is the main market at this capacity. A unit may also be part of a single-phase station power bank, but that is a distinct application rather than the usual configuration.
Common examples include a 5 MVA collector or service transformer, an industrial medium-voltage substation transformer, and a solar inverter step-up or battery energy storage system (BESS) transformer. The right role depends on the winding voltages, connection, duty and project design—not kVA alone.
- Grid or facility service and industrial distribution
- Solar collection and inverter step-up
- Battery energy storage projects
- Station power bank components
FLAFull-Load Amps for a 5000 kVA Transformer
Rated full-load current at common California voltages. Single-phase: amps = kVA × 1000 ÷ volts. Three-phase: amps = kVA × 1000 ÷ (1.732 × volts). Use the nameplate voltage of your unit.
| Phase | Voltage | Full-load amps |
|---|---|---|
| Three-phase | 480 V | 6,014 A |
| Three-phase | 4.16 kV | 694 A |
| Three-phase | 12 kV | 241 A |
| Three-phase | 12.47 kV | 231 A |
| Three-phase | 20.78 kV | 139 A |
| Three-phase | 34.5 kV | 83.7 A |
| Three-phase | 66 kV | 43.7 A |
02Types of 5000 kVA Transformers You May Have
At this rating, equipment may be a three-phase pad-mount, substation or power transformer, primary-unit-substation transformer, medium-voltage dry-type unit, or cast-resin transformer. Solar and BESS step-up designs are also relevant. See our pages on three-phase pad-mount transformers, substation and power transformers, primary unit-substation transformers and medium-voltage dry-type transformers for configuration details.
A conventional pole-mount transformer is not a typical 5000 kVA installation. However, a transformer associated with a station bank or a less common design should be evaluated from its actual nameplate and construction rather than rejected based on the category alone.
03Voltage Combinations and California Applications
The full-load amps chart on this page shows current for selected three-phase voltage points, including common medium-voltage and low-voltage examples. A 5 MVA unit could have a medium-voltage winding paired with a facility or collection-system winding; the actual primary and secondary arrangement varies with the application. Some units are designed for step-up service, so do not assume the lower voltage is always the secondary.
California systems vary by utility and service area. The nameplate may show values such as 12 kV, 12.47 kV, 20.78 kV, 34.5 kV or other ratings; the listed 66 kV chart point can also be relevant to subtransmission equipment. These are not interchangeable. Confirm the exact voltage, winding connection, taps and phase against the nameplate and project requirements.
- Read the row matching the winding voltage—not a nearby nominal value.
- Use the chart as a reference for full-load current, not as a substitute for nameplate or engineering data.
- Check whether the unit is step-down, step-up or part of a bank.
How to Read the Full-Load Amps Chart
Select the correct phase and voltage, then read across to the corresponding current. The three-phase chart values apply at the listed voltage and full 5000 kVA rating; primary and secondary windings can have different full-load currents because their voltages differ. For the underlying kVA-to-current relationship and rating terminology, see the transformer kVA and amps guide.
04Check Base Rating and Fan-Stage Capacity
A 5000 kVA label may refer to the base rating or a rating available with fans operating. Larger power transformers can have multiple cooling stages, so a nameplate might show a sequence such as ONAN/ONAF/ONAF with different capacity at each stage. Do not assume the highest figure is continuously available without the specified cooling equipment.
Photograph every rating line. Include fan or pump information if shown, and note whether accessories are present. For a fair review, the buyer needs to distinguish the base rating from each forced-cooling stage and confirm that the supporting equipment is included.
05Physical Size, Weight and Removal Planning
A 5 MVA transformer is substantial equipment, but its dimensions and weight vary by manufacturer, voltage design, insulation, cooling system, tank construction and accessories. A liquid-filled substation unit with radiators and other fittings can differ significantly from a dry-type unit or a pad-mounted design. Use the nameplate or shipping records for actual weights and dimensions rather than relying on a size estimate.
For an offer, share the site location and any known access limits, loading arrangements or removal constraints. California Transformer Buyer states in the written offer who handles loading or rigging and freight. The owner’s qualified electrical contractor or serving utility is responsible for electrical isolation and disconnection; sellers should only photograph equipment they are authorized to access from a safe position.
06What Affects the Value of a Used 5000 kVA Transformer
Value depends on whether the unit is used, new-surplus or otherwise surplus; its exact ratings and configuration; and the demand for that design. Primary and secondary voltages, phase, winding connection, impedance, BIL, cooling class, temperature rise, winding material and manufacturer all help establish what the transformer is and where it may be useful.
Condition and documentation matter. Age, leaks, corrosion, bushing damage, missing accessories, test reports and service history can affect the assessment. For liquid-filled units, fluid type and quantity, PCB records and available oil or electrical test results are important. A unit with fans, switches, gauges or other specified accessories may be more complete than one missing them. See what affects a used transformer’s value for more detail.
- New-surplus versus previously energized condition
- Nameplate ratings, voltages and cooling stages
- Test reports and maintenance records
- Fluid and PCB documentation, when applicable
- Completeness, site access and removal complexity
Share PCB and Environmental Records
Do not infer PCB status from appearance or age alone. Provide labels, test results and records you have; unknown status may require further determination. Rely on testing, documentation and qualified environmental professionals for handling and compliance decisions. California’s requirements for PCB-containing oil differ from federal categories, and the correct pathway depends on the facts; this information is not legal advice.
07What to Send for an Offer
Send clear photos of the nameplate and the transformer overall, along with the quantity, California location and condition. Rocky may ask for additional records or details before preparing an offer. You can use the transformer sale submission process or text photos to (951) 403-5738. Reviewing a transformer costs nothing and creates no obligation.
- Nameplate: manufacturer, serial number, year and all kVA stages
- Voltages, phase, taps, connection, impedance and cooling class
- Fluid type, gallons and PCB label or records, if applicable
- Test reports, condition notes and included accessories
- Quantity, site location and known access limitations
Written Terms Before Pickup
If the unit is a fit, the written offer states the price, what is included, who handles loading or rigging and freight, and payment terms and timing. The pickup is scheduled according to those written terms. The seller must own the transformer or have authority to sell it; utility-owned equipment cannot be sold by a property owner.
08Compare Nearby Capacity Ratings
A 5000 kVA nameplate is a specific capacity, but neighboring ratings may appear in the same project or equipment yard. If the label shows a different capacity, compare it with 3750 kVA transformers, 7500 kVA transformers or 10 MVA transformers. Use the full nameplate rating and cooling-stage details rather than rounding to the nearest size.
For a California-based review, call or text California Transformer Buyer at (951) 403-5738, or send the equipment details through the website. The offer process is based on the individual transformer, its condition, documentation and logistics.
kVANearby Transformer Sizes We Buy
FAQ5000 kVA Transformer FAQ
Can you buy a 5000 kVA transformer that is already installed?
California Transformer Buyer reviews installed equipment located in California, but the unit must be accessible for assessment and the seller must own it or have authority to sell it. Send the nameplate and overall photos taken from a safe position, plus the location and condition. Electrical isolation and disconnection must be handled by the owner’s qualified electrical contractor or serving utility, not by the seller.
Is every 5000 kVA transformer three-phase?
No. Three-phase is the main market configuration at 5000 kVA, but a single-phase unit may exist as part of a station power bank or a specialized arrangement. The phase should be confirmed from the nameplate. If a listing or project record says 5000 kVA without phase information, provide a clear nameplate photo so the configuration can be checked.
Will a 5000 kVA transformer work as a replacement for another 5 MVA unit?
Not necessarily. Matching kVA alone does not establish compatibility. The replacement must suit the system’s voltage, phase, winding connection, taps, impedance, BIL, cooling and installation requirements. Have the project engineer or qualified electrical professional verify those details against the equipment and system design before treating a transformer as a suitable replacement.
What if the nameplate gives different ratings for cooling stages?
Send a photo that captures every rating and cooling designation. A unit may have a base capacity and higher ratings when fans or other forced-cooling equipment are operating. Those figures describe different operating conditions, so the review needs to identify which rating applies and whether the required cooling accessories are present and included.
Do you consider new-surplus 5000 kVA transformers?
Yes. California Transformer Buyer reviews new-surplus equipment located in California, as well as used and other surplus units. Include whether it has ever been energized, whether it remains crated or on skids, and any factory test report or shipping documentation. The written offer will specify what equipment and accessories are included and the applicable pickup and payment terms.
Can I sell a transformer owned by the utility at my property?
No. A property owner cannot sell equipment owned by a utility. Confirm ownership or your authority to sell before requesting an offer. If ownership is unclear, check the project, service or purchase records and contact the relevant owner. California Transformer Buyer can assess only equipment that the seller owns or is authorized to sell.