41/ETC-II(P)/2025-2026

Overhauling & servicing of single pole Diverter of 132/33 KV 63/40/20 MVA Power Transformer. Details of work given below :- 1. Perform the pre-overhauling test :- Continuty test & ratio test. 2. Check OLTC munal operation, raise & lower side. 3. Drain the oil of OLTC Diverter Chamber & OLTC conservator Tank in clean & moisture free empty barrel. 4. Remove diverter switch assembly from diverter chamber after opening of OLTC cover. 5. Check & clean the corban deposition in the OLTC diverter switch chamber with the help of power transformer oil. 6. Cleaning of moving & fixed contacts of diverter switch and diverter chamber with the help of hot transformer oil. 7. Check & correct the diverter operation. 8. Check the value of transition (shunt) resistance in the resistance basket assembly. 9. Check & correct the looseness & tighteness of resistance basket assembly connection. 10. Replace the required material like contacts, top oil seal or O-ring including other consumable Item and after that fill the OLTC with oil checking BDV of oil (BDV should be min. 60 KV), fresh oil if required will be provided by UPPTCL. 11. Re-assemble of diverter switch after cleaning of diverter chamber & then check oil level in conservator tank. 12. Release the air from the OLTC chamber by changing the taps of OLTC manually. 13. Check for looseness & tighteness of the drive mechanism of OLTC. 14. Check & correct all the gear box & soft allignment (greasing of gear box). 15. Check & test all the electrical contacts & relay in diverter mechanism (MCB, Motor operation & Raise/Lower operation). 16. Check & correct all the electrical connection & diverter mechanism box & correct electrical operation through local control & remote control. 17. Perform post overhauling test : continuty test, ratio test). Details of transformers :- 1. 132 KV S/S Karchhana - 40 MVA T/F-I (PME Make, Mfg-2012) 2. 132 KV S/S Koraon - 20 MVA T/F- I & II (ECE Make, Mfg-2012) 3. 132 KV S/S Meja - 63 MVA T/F (T&R Make, Mfg-2017) 4. 132 KV S/S Jari - 40 MVA T/F-I (Technical Associate Make, Mfg-2016) 5. 132 KV S/S Salayakhurd - 40 MVA T/F-I & II (Technical Associate Make, Mfg-2016). 6. 132 KV S/S Naini Complex - 40 MVA T/F-III (Technical Associate Make, Mfg-2018