
Up to 20 MVA | Up to 33 kV | IS 11171 / IEC 60076-11 | Fire-Safe | Oil-Free
Marsons Dry Type Transformers use air as the cooling medium and solid or resin insulation — eliminating fire risk entirely. They are the preferred choice for indoor installations, confined spaces, and locations with stringent fire safety mandates. Available in open ventilated (AN) and cast resin encapsulated designs. Zero oil means zero maintenance associated with oil management.



| Parameter | Value / Description |
|---|---|
| Rating Range | Up to 20 MVA (custom ratings available) |
| Voltage Class | Up to 33 kV |
| Cooling | AN (Air Natural) | AF (Air Forced with fans) |
| Insulation Class | Class F / Class H — open ventilated or cast resin encapsulated |
| Standards | IS 11171, IEC 60076-11 |
| Protection Class | IP00 (open) to IP54 (enclosed) depending on enclosure specification |
| Insulation System | Cast resin (VPI or cast coil) or open ventilated with Class F/H insulation materials |
| Key Safety Advantage | Zero oil — inherently fire-safe. No oil spillage, no Buchholz relay, no oil testing required. |
| Optional Extras | Forced air cooling fans with thermostat, PTC thermistors in windings, temperature monitoring relay |
| Enclosure Options | Open frame | IP21/IP31 ventilated | IP54 sealed |
From standard distribution to specialized power transformers, explore our robust, precision-engineered solutions designed to meet your exact energy infrastructure requirements.

A quality policy is a reflection of the endeavors and aims of the organization. Quality has always been a benchmark at Marsons.
Our uncompromising stance on quality and strict adherence to ISO 9001:2008 standards furnish our customers with the very best and reliable products.
To maintain these rigorous standards, our quality control activities are seamlessly integrated into every stage of the production cycle.
These core activities can be summarized as: custom order management, a strict approval system for all vendors, uncompromising manufacturing supervision, and comprehensive testing and inspection.
Our testing departments, utilizing high-end equipment, play a decisive role in the implementation of our quality program. We operate two laboratories, both equipped with modern machinery and precision instruments.
To ensure the highest accuracy, tests are conducted separately. One laboratory is strictly allotted for high/medium voltage transformers, and the other for medium/low voltage transformers.
Our quality is backed by accredited infrastructure. Our fully equipped NABL accredited laboratory can efficiently carry out all required routine and type tests, including Impulse lightning tests and Temperature rise tests.
This facility allows us to rigorously test various ratings of Power Transformers up to the range of 200 MVA 220 kV class using various conventional, state-of-the-art, and modern equipment.

Ready to power your infrastructure? Contact our experts today to discuss our wide range of ISO-certified distribution and power transformers, backed by 65 years of industry trust and credibility.
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