IS 1180 (Part 1)
Electrical - Out door type Oil immersed Distribution Transformers upto and including 2500 kVA, 33 KV-specification Part 1 Mineral oil immersed
Summry
Outdoor type oil-immersed distribution transformers up to 2500 kVA, 33 kV, are electrical devices that step down high voltage to lower levels for distribution. They use mineral oil for insulation and cooling, ensuring safe operation, heat dissipation, and long-term reliability in outdoor environments for industrial, commercial, and residential power supply.
Why BIS Certificate is Mandatory for Out door type Oil immersed Distribution Transformers upto and including 2500 kVA, 33 KV-specification Part 1 Mineral oil immersed
BIS certification is mandatory to ensure that outdoor oil-immersed transformers meet Indian safety, performance, and quality standards. Certification verifies insulation, cooling, voltage handling, and mechanical construction. It prevents the use of substandard transformers that may cause failures, fire hazards, or electrical accidents, ensuring reliability and consumer safety in power distribution networ
What is BIS Certified for Out door type Oil immersed Distribution Transformers upto and including 2500 kVA, 33 KV-specification Part 1 Mineral oil immersed
The BIS certified specification for outdoor oil-immersed distribution transformers is defined under IS 1180 (Part 1) – Mineral Oil Immersed. It specifies requirements for rated capacity, voltage levels, insulation, oil quality, mechanical construction, testing procedures, and safety measures. Compliance guarantees performance, reliability, and adherence to Indian Standards for electrical equipment.
Test required for Out door type Oil immersed Distribution Transformers upto and including 2500 kVA, 33 KV-specification Part 1 Mineral oil immersed
Raw Materials
| Title | Mandatory/Optional |
|---|---|
| CRGO Electrical Steel | Optional |
| Amorphous core material | Optional |
| Copper/Aluminium conductor | Optional |
| Kraft Paper | Optional |
| Press Board | Optional |
| Bushings | Optional |
| Dimensions of Bushings | Optional |
| Gasket | Optional |
| Mineral Oil | Optional |
| Transformer Tank | Optional |
| Bolts, Nuts, Washers | Optional |
General
| Title | Mandatory/Optional |
|---|---|
| Permissible Flux density ,Current and Voltage | Optional |
| Minimum clearances in air | Required |
| Construction of Transformer Tank | Required |
| Painting of Transformer Tank | Required |
| Conservator for non sealed type transformer | Required |
Routine Tests (To be conducted on all units)
| Title | Mandatory/Optional |
|---|---|
| Measurement of Winding Resistance | Required |
| Measurement of voltage ratio and check of phase displacement | Required |
| Measurement of short circuit impedance (principal tapping, when applicable) & load loss at 50 percent & 100 percent load | Required |
| Measurement of no-load loss & current | Required |
| Measurement of insulation resistance | Required |
| Induced Overvoltage withstand Test | Required |
| Separate-source voltage withstand test | Required |
| Pressure Test | Required |
| Oil Leakage Test | Required |
Type Tests: To be carried out at the first instance and whenever there is any change in design
| Title | Mandatory/Optional |
|---|---|
| Lightning Impulse Test | Optional |
| Temperature Rise Test | Optional |
| Short circuit withstand test (up to 200 kVA) | Optional |
| Pressure Test | Optional |
Benefits of BIS Certification for Out door type Oil immersed Distribution Transformers up to and including 2500 kVA, 33 KV-specification Part 1 Mineral oil immersed
-
Assured Safety and Reliability
BIS certification ensures transformers meet safety standards, reducing risks of fire, electrical faults, and insulation failures. -
Guaranteed Quality Performance
Certified transformers comply with standards for voltage regulation, load handling, and cooling efficiency, ensuring consistent and reliable operation. -
Compliance with Legal Requirements
BIS certification is mandatory in India, enabling manufacturers and importers to sell transformers legally and avoid regulatory penalties. -
Extended Lifespan and Durability
Certification ensures the use of quality materials and proper design, resulting in longer service life and lower maintenance costs. -
Enhanced Market Trust and Credibility
BIS-certified transformers are widely accepted by utilities, industries, and government projects, increasing brand reputation and market competitiveness.