Full Supply & Erection Scope
- 1. Transformer Supply: Oil-immersed (ONAN/ONAF) and Cast Resin Dry-Type (CRT) transformers from 100 kVA to 25 MVA up to 33kV/66kV rating.
- 2. Civil Foundation & Oil Sump: Construction of RCC plinths, oil containment soak pits, gravel fire barriers, and anti-vibration pad mounting.
- 3. Rigging & Placement: Heavy crane positioning, skidding onto foundation rails, and secure torque anchoring.
- 4. Bushing & Cabling: HT/LT cable terminations, busduct trunking connections, neutral CT wiring, and breather silica gel recharging.
Testing & Commissioning Suite
- 1. Vacuum Oil Filtration: Mobile high-vacuum oil dehydration achieving Breakdown Voltage (BDV > 60 kV) and moisture < 10 PPM per IS 6792.
- 2. Turns Ratio & Vector Group: Voltage ratio verification across all tap positions and phase displacement confirmation.
- 3. Winding Resistance & Megger: Kelvin bridge resistance checks and 2.5kV/5kV insulation resistance with Polarization Index (PI).
- 4. Protection Calibration: Buchholz relay trip testing, Oil Temperature (OTI) & Winding Temperature (WTI) alarm interlocks.