Design Requirements
1. Basic Electrical Requirements
These values come from your electrical system design. If unsure, consult your electrical engineer.
The maximum power the transformer can deliver. 1500 kVA = 1.5 MVA. Common sizes: 500, 750, 1000, 1500, 2000, 2500 kVA. Larger = more expensive.
The incoming utility voltage. Check your utility connection agreement. 13.8 kV is most common for commercial/industrial in North America.
The voltage your facility needs. 480V is standard for industrial equipment. 208V/240V for smaller facilities. Match your main electrical panel.
Determined by your location's power grid. North America uses 60 Hz.
Almost all commercial/industrial applications use three-phase power for efficiency and motor operation.
Dyn11 is standard for most applications - provides a neutral for single-phase loads. Your electrical engineer will specify if different is needed.
Affects bushing configuration, switching requirements, and fault current design. Loop feeds require load-break bushings on both sides.
Helps OEMs understand design priorities — data centers need redundancy, renewables need harmonics handling, oil & gas needs hazardous area ratings.
Number of identical units needed. Multiple units typically get better pricing.
Location helps estimate shipping costs and may affect design for local climate conditions.
When do you need the transformer delivered? Lead times typically range from 12-52 weeks depending on size and region.
2. Performance & Efficiency Choices
These choices affect cost, efficiency, and delivery time. Use the impact badges to guide decisions.
Controls voltage stability and fault current. 5.75% is standard. Lower = better voltage regulation but higher short-circuit current (needs larger breakers). Higher = lower fault current but more voltage drop.
Cooling stages add power capacity. ONAN = base self-cooled rating.ONAF adds fans for +33%. OFAF adds forced oil circulation for +67%.
Copper costs more but is more efficient and compact. Aluminum saves 30-40% on conductor cost but transformer is larger. For high-efficiency requirements, choose copper.
NLTC adjusts voltage ratio when de-energized — standard for most applications. OLTC allows voltage adjustment under load — required for voltage regulation on feeders or large facilities. OLTC adds significant cost ($15K-$45K).
Mineral oil is the industry standard for outdoor oil-filled transformers. Natural ester offers a higher fire point and is biodegradable — preferred near sensitive environments. Silicone fluid is used where fire resistance is critical (indoor, near buildings).
Conservator with bladder is standard — allows oil expansion while preventing moisture ingress. Sealed tank eliminates the conservator for a simpler, lower-maintenance design. Nitrogen blanket provides inert gas protection for critical applications.
A Transformer Automation Controller like the SEL-2414 provides real-time monitoring, SCADA integration, condition-based alerts, and remote diagnostics. Recommended for critical infrastructure, unmanned substations, and assets requiring predictive maintenance.
Select all regions you would accept. More regions = wider price and lead time range.
USA
Premium pricing, 26-52 week lead time
North America
USA/Canada/Mexico, 20-40 weeks
Global (excl. China)
Broader supplier pool, 16-36 weeks
China
Lowest pricing, 12-24 weeks
Not FEOC compliant
Require FEOC Compliance
Required for IRA Section 45X tax credits, federal/state projects, and critical infrastructure.
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Advanced Specifications
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