Industrial Projects: Selection of High Power Transformers.
- Grupo Edmar
- Oct 21
- 5 min read
October 21, 2025 - Industrial Projects: High Power Transformer Selection
Industrial Projects: Selection of High Power Transformers.
In industrial projects, electrical power is the heart that drives every operation. From starting large motors, smelting furnaces, pumping systems, to automated production lines, everything depends on a reliable power source. This is where the high-power transformer comes into play, an essential component for ensuring a stable and efficient power supply in industrial plants.
In this article, we'll discuss how to select the right high-power transformer for your industrial project , the most important factors to consider, the available types, their integration into the plant system, and why having a reliable supplier like Grupo Edmar can make all the difference.
Why "high power" in industrial environments?
High-power transformers are designed to operate under very high loads and maintain continuous performance without compromising safety or efficiency. In industrial projects—such as manufacturing plants, steel mills, petrochemical plants, cement plants, or large industrial parks—the energy demands are enormous and constant.
Therefore, a high-power transformer must not only transmit electricity: it must maintain the stability of the electrical system , withstand load peaks, reduce losses, and withstand demanding environmental conditions.
Real-life example: In a continuous production plant, where machines operate 24/7, a transformer failure can shut down the entire line and generate losses of thousands of pesos per hour. Therefore, design, insulation quality, and cooling capacity are vital.
Key Selection Factors.
Selecting the right transformer involves more than just looking at voltage and power. Each industry has specific conditions that must be considered from the design stage:
Nominal capacity (kVA or MVA): Must cover current demand plus a reserve for future growth.
Primary and secondary voltage: Ensures compatibility with the medium and low voltage system.
Operating frequency: In Mexico and most of America, 60 Hz is the standard.
Load type: Motors, ovens or welding systems require different conditions than lighting or air conditioning.
Location: A transformer in a closed room does not require the same conditions as one outdoors.
Efficiency level: Energy losses in high-power transformers can significantly impact operating costs.
Regulatory requirements: Compliance with standards such as NOM, IEC, IEEE, or NMX ensures safety and reliability.
Ease of maintenance and spare parts available.
Tip: Never oversize or undersize your transformer. Both errors are costly: the first, in unnecessary investment; the second, in failure and overheating.
Types of High Power Transformers and their Application.
Depending on the industrial environment and installation conditions, different types of transformers can be chosen. The most common are listed below:
Dry-type transformers (solid resin or encapsulated): Ideal for interiors or environments where there is a risk of fire or contamination. They do not use oil, require less maintenance, and offer high safety. Examples: food plants, pharmaceutical plants, or industrial buildings.
Oil- filled (submersible) transformers : These use dielectric oil to cool and insulate the windings. They are more common in outdoor installations or with higher power levels. For example, industrial substations or plants with external high-voltage supplies.
Pedestal-type or special power transformers: Designed for underground networks or industrial parks where easy access for maintenance is required.
Transformers with ONAN/ONAF cooling systems: Natural or forced cooling, depending on the load and ambient temperature.
Each type of transformer has specific advantages, and the correct choice depends on the environment and electrical demands of the project .
Load Calculation and Growth Projection.
Before choosing a transformer, it's essential to conduct a detailed load analysis . This calculation allows you to estimate how much power is required and how it will evolve over time.
Recommended steps:
List the electrical equipment that will operate in the plant (motors, ovens, lighting, etc.).
Calculate total demand considering simultaneity and power factors.
Analyze the load factor , which indicates how much average energy the plant consumes in relation to the maximum installed power.
Add a growth margin , ideally 15% to 30%.
Select the transformer based on this data plus operating conditions (temperature, altitude, humidity).
A common mistake is sizing the transformer only for the current load. This can result in future overloads or the need for premature replacement. Grupo Edmar can advise on load calculations and recommend the most appropriate equipment for projected growth.
Energy Efficiency and Loss Reduction.
In high-power transformers, energy efficiency is a priority. A small improvement in performance can represent significant long-term economic savings .
Factors influencing efficiency:
Magnetic core design (lower hysteresis and eddy currents).
Quality of materials and insulation.
Level of losses under no-load and under load.
Efficient cooling system.
Electrical losses (in copper and iron) generate heat and reduce the equipment's lifespan. Therefore, modern Edmar Group transformers are manufactured with low-loss materials and optimized designs to operate at maximum efficiency.
Integration of the Transformer into the plant system.
Correct integration of the transformer is essential to ensure its performance and safety.
Aspects to consider:
Substation design : Space, ventilation, accessibility and safety.
Electrical connections: Voltage compatibility, disconnectors, fuses and switches.
Protections: Overtemperature relays, lightning rods, and physical grounding systems.
Monitoring: Supervisory systems that allow for the timely detection of overloads or failures.
Preventive maintenance plan : Periodic inspection of connections, temperature measurement and cleaning.
Professional installation, coupled with proper maintenance, ensures a long transformer life and uninterrupted operation.
Risks and How to Mitigate Them.
High-power industrial transformers are exposed to various risks. Detecting and mitigating them early can prevent costly operational downtime.
Common risks:
Continuous overloads.
Power surges or current spikes.
Cooling system failures.
Excessive vibrations.
Installation in environments with high humidity or dust.
Preventive measures:
Correctly size the power.
Install thermal protections and monitoring relays.
Maintain adequate ventilation.
Carry out periodic inspections.
Train maintenance staff.
A preventive maintenance program, along with technical support from the manufacturer, reduces the risk of serious failures and prolongs the life of the transformer .
How to choose your supplier and why choose Grupo Edmar.
Selecting a good supplier is just as important as choosing the transformer. Always look for a manufacturer with proven experience, certified quality, and after-sales service.
Edmar Group offers:
Domestic manufacturing of high and medium power transformers.
Compliance with regulations.
Specialized personnel in technical advice.
Quality assurance and support.
Extensive experience in industrial projects throughout Mexico.
By working with a local manufacturer with the technical and production capabilities, you reduce delivery times and receive direct support for any needs.
Selecting a high-power transformer should not be taken lightly. A well-planned decision guarantees efficiency, safety, and operational continuity in your industrial plant. Relying on a reliable manufacturer like Grupo Edmar ensures you have equipment designed for your needs, with technical support, quality materials, and the guarantee of a Mexican company with more than 40 years of experience in the electrical sector.
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