High-Integrity Cast Resin Transformers (CRT) for Critical Substations
URJA Techniques (India) Pvt. Ltd., an established transformer engineering and manufacturing powerhouse since 1996, supplies custom-engineered Cast Resin Dry Type Transformers (CRT) for demanding electrical systems across India, the Middle East, Southeast Asia, and Africa. Managed by seasoned technocrats with deep domain expertise across core building, electromagnetic calculation, vacuum impregnation, and precision testing, URJA delivers non-hygroscopic, fire-safe dry-type solutions up to 5 MVA in the 33 kV voltage class.
Our modern manufacturing plant in MIDC Rabale, Navi Mumbai, is ISO 9001:2015, ISO 14001:2015, and ISO 45001:2018 certified. Operating to stringent IS, IEC 60076-11, and ANSI/IEEE standards, each transformer undergoes comprehensive routine tests—including partial discharge measurement, full-wave lightning impulse testing, temperature rise validation, and dielectric assessments—ensuring total operational resilience for critical infrastructure.
Vacuum Epoxy Encapsulation & Design Architecture
In a cast resin transformer, the high-voltage (HV) and low-voltage (LV) windings are encapsulated in high-grade, quartz-filled epoxy resin inside dedicated vacuum-casting autoclaves. This void-free vacuum molding process yields a monolithic, non-flammable, and self-extinguishing barrier impervious to humidity, chemical fumes, salt spray, and heavy airborne contamination.
Unlike oil-filled units, dry-type CRT units do not employ combustible liquid coolants, eliminating fire risk, oil containment dikes, gas accumulation relays, and periodic dielectric liquid testing. Natural air circulation (AN) or forced air cooling (AF via temperature-controlled cross-flow blowers) ensures rapid thermal dissipation, allowing temporary overload capacities up to 40% above nominal rating without degradation of insulation life.
- Non-Flammable & Self-Extinguishing: Certified to Fire Integrity Class F1 under IEC 60076-11; self-extinguishes instantly without emission of toxic gases or halogenated compounds.
- Superior Mechanical Short-Circuit Withstand: Fiberglass-reinforced epoxy provides exceptionally high dynamic shear resistance against axial and radial short-circuit stresses.
- Non-Hygroscopic & Tropicalized: Moisture absorption is practically nil. Ideal for coastal, high-humidity, and cyclic standby installations without prior dehumidification.
- Zero Maintenance Overhead: Completely free from fluid degradation, oil leakage risk, gasket decay, and silica gel breather regeneration.
- Compact Substation Footprint: Minimal safety clearance requirements allow indoor placement directly adjacent to primary load centres, minimizing low-voltage busbar cable losses.
Technical Specifications & Parameters
| Parameter | Standard / Specification Range |
|---|---|
| Power Rating Range | 100 kVA up to 5,000 kVA (5 MVA) |
| Voltage Class (Primary / Secondary) | HV up to 33 kV | LV: 415 V, 433 V, 690 V, 3.3 kV, 6.6 kV, 11 kV |
| Phases & Frequency | Three-Phase, 50 Hz / 60 Hz |
| Cooling System | AN (Air Natural) | AF (Air Forced Cooling with Fans for +40% Surge) |
| Insulation Class & Temp Rise | Class F (155°C) / Class H (180°C) with low hot-spot margin |
| Environmental / Fire / Climatic Classes | E2 (Heavy Condensation/Pollution), C2 (Down to -25°C), F1 (Self-Extinguishing) |
| Enclosure Protection Degree | IP00 (Core & Coil only), IP21, IP23, IP31, IP33, up to IP54 Outdoor Sheet Steel |
| Tapping Arrangements | Off-Circuit Tap Links (±2.5%, ±5%) or On-Load Tap Changer (OLTC) |
| Winding Material | High-Conductivity Electrolytic Grade Copper or EC Grade Aluminum |
| Core Construction | Low-loss, Cold-Rolled Grain-Oriented (CRGO) Silicon Steel with 45° Step-Lap Mitred Joints |
| Applicable Standards | IEC 60076-11, IS 11171, ANSI / IEEE C57.12.01, BS EN 60076 |
Target Applications & Installation Scenarios
High-Rise & Commercial
Commercial complexes, hotel towers, and IT hubs where municipal building safety codes mandate strictly non-combustible electrical distribution.
Healthcare & Metros
Hospitals, underground metro substations, and airports demanding zero toxic emissions, low noise, and clean operation under peak utility load.
Process & Renewable Plants
Data centers, chemical processing lines, steel rolling mills, and renewable solar/wind installations demanding extreme environmental endurance.
Global Export Footprint & Verification
URJA cast resin dry type transformers have earned proven track records across harsh climatic operating zones. International EPC contractors, utilities, and heavy industrial buyers across the United Arab Emirates, Saudi Arabia, Nigeria, Kenya, South Africa, Tanzania, and Indonesia depend on URJA transformers for sustained thermal stability, low partial discharge (<10 pC), and minimal ownership lifecycle costs.
Each unit ships with full technical literature, structural CAD layouts, and certified factory routine test certificates validating loss evaluations, dielectric withstand, and acoustic levels.