The 225 kVA three phase pad mounted transformer is where projects start getting serious about load. It’s not an entry-level spec — it’s the capacity engineers reach for when 150 kVA is cutting it close or the project is expected to grow. Oil-filled, dead-front enclosure, built to ANSI/IEEE. Primary voltage from 2.4 kV to 34.5 kV, secondary configurable. Each unit is built and tested in-house before shipment.
Power Rating
225 kVA
Phase
Three Phase
Primary Voltage
2.4–34.5 kV
Secondary Voltage
208Y/120V–480V
Standard
ANSI/IEEE
Cooling
ONAN
Certification
CE Certified
225 kVA sits at an interesting point in the pad mounted range. It’s big enough to handle mid-size commercial facilities with room to spare, but it doesn’t bring the installation complexity or cost jump you get when you move into the 750 kVA range and above. For a lot of projects, this is the capacity where you stop second-guessing whether the transformer is big enough.
The build is the same as the rest of the range — cold-rolled silicon steel core, copper windings, mineral oil cooling, dead-front enclosure to ANSI/IEEE C57.12.28. What’s different at 225 kVA is the thermal headroom. The oil cooling system has more buffer between operating temperature and the thermal limit, which means it holds up better when the site is running close to full load regularly.
If you’re on 150 kVA and the load is already at 70–80% of capacity, or the project has a second phase coming, 225 kVA is usually the smarter call. The footprint difference is manageable.
Built for Load Growth
Expand without replacing
A lot of buyers end up at 225 kVA because the project has room to expand — a commercial building with a second phase, a facility adding equipment, a distribution point that needs to cover more connections over time. When demand goes up, you don’t have to swap the unit out. That’s a real-world cost saving that doesn’t show up in the initial price comparison.
More Thermal Headroom
ANSI/IEEE C57.12.28
The enclosure still meets ANSI/IEEE C57.12.28 — dead-front, lockable, suitable for public areas. At 225 kVA, the oil cooling system has more buffer between operating temperature and the thermal limit. That matters on sites that run close to full load regularly. Smaller units can handle it, but 225 kVA handles it with less stress on the system.
Custom Configurations
Engineering review included
Non-standard voltage combinations, specific impedance values, alternative connection types — these can all be worked through before production starts. If your project has specs that don’t match a standard catalog unit, tell us what you need and we’ll go through the engineering to confirm what’s possible.
Testing & Documentation
CE · ISO 9001:2015
Each unit goes through routine testing before it ships — ratio check, insulation resistance, no-load loss. As a 225 kVA pad mounted transformer manufacturer with CE, ISO 9001:2015, and ISO 14001, we can provide full documentation for customs, compliance review, or vendor list submissions.
The 225 kVA three phase pad mounted transformer works well for mid-size commercial buildings, facilities with variable or growing loads, and projects where pushing 150 kVA to its limit doesn’t make sense. It’s also a common spec for schools, healthcare facilities, and commercial developments where load demand isn’t always predictable from day one. For heavier requirements, the 300 kVA three phase pad mounted transformer is the next step up.
| Parameter | Standard Value | Custom Available |
| Rated Power | 225 kVA | — |
| Phase | Three Phase | — |
| Primary Voltage | 2.4–34.5 kV | Custom |
| Secondary Voltage | 208Y/120V, 240V, 480V | Custom |
| Frequency | 60 Hz | 50 Hz available |
| Connection Type | Dyn11, YNyn0 | Custom |
| Cooling Method | ONAN (Mineral Oil) | Vegetable Oil |
| Temperature Rise | 65°C | 55°C available |
| Insulation Class | Class A | — |
| Enclosure Type | Pad Mounted, Dead-Front | — |
| Enclosure Standard | ANSI/IEEE C57.12.28 | — |
| Transformer Standard | ANSI/IEEE C57.12.00/34 | IEC 60076 |
| Winding Material | Copper | Aluminum |
| Core Material | Cold-rolled Silicon Steel | — |
| Impedance Voltage | 3.10% – 5.75% | Custom |
| Certifications | CE, ISO 9001:2015 | GOST available |
Need something different? Most parameters can be adjusted. Send your project spec and we’ll confirm what’s possible.
Enclosure and Ventilation Panel
Factory shot of the finished unit, ready for shipment.
What is a 225 kVA three phase pad mounted transformer used for?
It’s used for mid-size commercial buildings, schools, healthcare facilities, retail developments, and similar projects where the load runs higher than 150 kVA handles comfortably. It’s also a common choice when the project expects load growth — the extra capacity means you’re not forced to replace the unit as demand increases.
How does 225 kVA compare to 300 kVA?
It comes down to your peak load and growth plans. If your connected load stays comfortably below 180 kVA, 225 kVA works fine. If you’re regularly running above that, or the project has a significant expansion phase, 300 kVA gives you more room. The physical size difference isn’t major — the decision is really about load margin.
What voltage options are available?
Primary voltage from 2.4 kV to 34.5 kV. Standard secondary outputs are 208Y/120V, 240V, and 480V. Other combinations are available. Tell us your grid supply voltage and the output you need — we’ll confirm what works.
Can this transformer be customized for non-standard specs?
Yes. Beyond voltage, we can adjust tap range, connection type (Dyn11, YNyn0, and others), impedance value, winding material, oil type, and enclosure finish. Non-standard configurations go through an engineering review before production — so if your project has specific requirements, we’ll go through them and confirm feasibility before you commit.
What standards does this transformer meet?
Manufactured to ANSI/IEEE C57.12.00 and C57.12.34. Enclosure meets ANSI/IEEE C57.12.28. CE documentation available. IEC 60076 configurations can be produced for projects outside North America.
How do I get a quote from a 225 kVA pad mounted transformer supplier in China?
Send us the rated capacity, primary and secondary voltage, quantity, installation country, and any certification requirements. If you have a spec sheet, attach it. We respond within 24 hours — for custom configurations we may have a few follow-up questions, but we’ll flag that upfront.
