WBIW/EE/MDMD/e-NIT- 20/2025-26/01

Opening the Transformer breather and refitting the same after changing the sillica jel including the supply of necessary gasket and silica jel.

Dehydration & filtration of power transformer oil to raise the dielectric strength to the value specified in IS including submission of test result. The cost includs man, machinary, and tools & plant hire charges to complete the at site as per direction of the EIC.

Maintenance and servicing of Dry type Cast Resin Transformer 11kv/.415 kv ( 1000kva/630 kva) , with engagement of suitable manpower and tools and tackles, testing equipments, air blowers etc as per manufacturer maintenance guideline including checking core and core assembly to ensure that HT tap links of all the three phase are at proper position and adequately tightened and locked, to check and ensure that all HT/LT connection nut bolts are fully tightened and locked, to check and ensure that the core, coil and its connections are thoroughly checked for any cobwebs, dust, dirt using air blower etc. Checking the enclosure perforated sheet/ mesh and clean thoroughly for cobwebs, dust, dirt to ensure adequate and proper ventilation of air through the same. Checking the Marshalling box , to check and ensure that Winding Temperature indicator (WTI) and Winding Temperature Relay (WTR), WTR alarm, trip contacts are in working condition and its temperature scanner/sensing thermisters are healthy and functional, to check and ensure that alarm trip circuit of WTI/WTR are working satisfactorily, also to check and ensure that HT/LT circuit breakers for its tripping on getting signals from WTI/WTR, to check WTI for its proper temperature setting for alarm and trip. Checking of HT/LT bushing and examine for dirt deposits and cleaning with non-fibrous, non fluffy cloth. Also checking of Earth resistance and to take corrective action if found more. Also taking note of winding temperature (WTI) hourly for at least seven days and submission of report mentioning the findings and test report for Insulation Resistance Test: HV-LV, HV-Earth, LV-Earth, Winding Resistance Test to check phase imbalance. (Note: The work shall be done on CRT, after isolation/ disconnection of HT/LT cables and ensuring that its HT/LT windings are solidly earthed at its main terminals. Also It must be ensured before closing that no metallic parts viz nuts, bolts, electrical cut wire pieces, cotton waste, spanners etc are left inside the enclosure/ on core/ on coils as this cause hazardous accident and failure of the CRT) :- job

Maintenance and servicing of Dry type Cast Resin Transformer 11kv/6.6 kv (2000kva/1600kva), with engagement of suitable manpower and tools and tackles, testing equipments, air blowers etc as per manufacturer maintenance guideline including checking core and core assembly to ensure that HT tap links of all the three phase are at proper position and adequately tightened and locked, to check and ensure that all HT/LT connection nut bolts are fully tightened and locked, to check and ensure that the core, coil and its connections are thoroughly checked for any cobwebs, dust, dirt using air blower etc. Checking the enclosure perforated sheet/ mesh and clean thoroughly for cobwebs, dust, dirt to ensure adequate and proper ventilation of air through the same. Checking the Marshalling box , to check and ensure that Winding Temperature indicator (WTI) and Winding Temperature Relay (WTR), WTR alarm, trip contacts are in working condition and its temperature scanner/sensing thermisters are healthy and functional, to check and ensure that alarm trip circuit of WTI/WTR are working satisfactorily, also to check and ensure that HT/LT circuit breakers for its tripping on getting signals from WTI/WTR, to check WTI for its proper temperature setting for alarm and trip. Checking of HT/LT bushing and examine for dirt deposits and cleaning with non-fibrous, non fluffy cloth. Also checking of Earth resistance and to take corrective action if found more. Also taking note of winding temperature (WTI) hourly for at least seven days and submission of report mentioning the findings and test report for Insulation Resistance Test: HV-LV, HV-Earth, LV-Earth, Winding Resistance Test to check phase imbalance. (Note: The work shall be done on CRT, after isolation/ disconnection of HT/LT cables and ensuring that its HT/LT windings are solidly earthed at its main terminals. Also It must be ensured before closing that no metallic parts viz nuts, bolts, electrical cut wire pieces, cotton waste, spanners etc are left inside the enclosure/ on core/ on coils as this cause hazardous accident and failure of the CRT) :- job

Following tests are to be performed for the 11 kv VCB, 4 panel (1 no incoming and 3 nos outgoing) and test report to be submitted in tabular format in triplicate mentioning the instrument used with calibration certificate. I Electrical Test: Insulation Resistance Test (5 kV): Phase-Phase, Phase-Earth. H.V test of 4 nos VCB Panels ii CT/PT & Metering Compartment IR test for CT/PT secondaries. Polarity & ratio checks. Check wiring tightness, PT fuses. iii Busbar System IR test of busbars. Inspect for dust, corona marks, rodents. iv Cable Terminations Inspect heat shrink/ epoxy terminations. IR testing of cables. Tightness check & thermography. v Transformer IR & H.V test. For 3 nos transformer vi Earthing System Earth continuity inside panels. Earth electrode resistance. Check earthing of CT/PT frames and panel body.

Taking out samples of oil and carrying out chemical test of oil in respect of its acidity test through reputed test house and submission of Test Result.

Takingout sample of oil from power/voltage transformer, OCB etc. & testing their dielectric strength according to specification and submission of test result.

120 -185 sq. Mm