COMPREHENSIVE MAINTENANCE OF TRANSFORMER VCB, VOLTAGE STABLIZER AND CONNECTED ITEM AT AGE I R AND D MANALI

Amount

Disconnecting cable and Earthing connections of Servo voltage stabilizer of capacity 400 KVA , 3 phase to carry out overhauling of stabilizer comprising of the following:- (i) Draining out oil from chamber. (ii)Opening top cover , disconnecting winding connection from bushings and taking out carefully core assembly complete with winding. (iii) Checking compactness of core & tightening the same where required. (iv)Chemical washing of winding to remove dirt,dust & carbon particles (v)Cleaning of oil tank to remove oil sludge followed by painting of inner surface of tank with zinc chromate base paint (vi)Refixing of core & winding assembly and making connection with HT/LT bushing . (vii)Replacement of worn out gaskets & nut/bolts. (viii)Refilling of oil duly filtered/dehydrated/fresh oil. Removing of old damaged unserviceable Burnt dimmer coil and replacement new dimmer coil of 400KVA rating complete all as specified and as directed by Engineer-in-Charge. Material and labour for in replacement of carbon brush of all dimmer coils 400KVA stabilizer complete all as specified and as directed by Engineer-in-Charge.

Disconnecting cable and Earthing connections of Servo voltage stabilizer of capacity 250 KVA , 3 phase to carry out overhauling of stabilizer comprising of the following:- (i) Draining out oil from chamber. (ii)Opening top cover , disconnecting winding connection from bushings and taking out carefully core assembly complete with winding. (iii) Checking compactness of core & tightening the same where required. (iv)Chemical washing of winding to remove dirt,dust & carbon particles (v)Cleaning of oil tank to remove oil sludge followed by painting of inner surface of tank with zinc chromate base paint (vi)Refixing of core & winding assembly and making connection with HT/LT bushing . (vii)Replacement of worn out gaskets & nut/bolts. (viii)Refilling of oil duly filtered/dehydrated/fresh oil. Removing of old damaged unserviceable Burnt dimmer coil and replacement new dimmer coil of 250 KVA rating complete all as specified and as directed by Engineer-in-Charge. Material and labour for in replacement of carbon brush of all dimmer coils 250KVA stabilizer complete all as specified and as directed by Engineer-in-Charge.

Removing of old damaged unserviceable Burnt dimmer coil and replacement new dimmer coil of 400KVA rating complete all as specified and as directed by Engineer-in-Charge.

.Removing of old damaged unserviceable Burnt dimmer coil and replacement new dimmer coil of 250KVA rating complete all as specified and as directed by Engineer-in-Charge.

M&L for in replacement of carbon brush of all dimmer coils 400KVA /250 kva stabilizer complete all as specified and as directed by Engineer-in-Charge.

M&L for in replacement of finger set 400/250 kva stabilizer complete all as specified and as directed by Engineer-in-Charge.

M & L for Earthing complete with galvanized earth plate electrode 60 cm x 60cm x 6mm thick buried directly in ground to the depth of not less than 2.25 mtr below ground level with top edge of earth plate or a depth not less than 1.50 m below ground level connected to GI strip 32 x 6mm as earth lead by means of galvanized bolts, nuts check nuts and washers and necessary excavation and earth work PCC 1:2:4 type B-1 using 20mm graded brick aggregate for earth pit RCC cover , charcoal & common salt filled in alternate layers funnel with 20mm bore light grade watering pipe, 40mm dia GI pipe light grade for protection of GI strip, wire mesh and connected to earth point including testing on all as specified and shown in electric plate No 3 of SSR part I.

M & L in replacement silica gel breathers assembly transparent PVC body with top and bottom posn pressed with metallic cover filled with silica gel blue in colour and suitable for fixing on existing size 15/20/25 mm dia as per situ requirement for transformers of capacity UP TO 400 KVA.

Disconnecting and taking down of transformer indoor/outdoor type 11000/415 volts having capacity 250 TO 400 KVA, transportation to contractor’s workshop for repairs, strip opening of transformer after unscrewing nuts /bolts screws and connected accessories such as breather, conservator tank, temp gauge, taking out the core for replacement of defective parts and transportation back to the site after repairs and installing, connecting up, testing and commissioning at the site complete all as specified and directed. Notes : - (a) Transformer oil shall be drained out by the contractor in suitable capacity MS drums to be arranged by the contractor. The said drained out transformer oil shall be refilled in the transformer duly dehydrated after repair and the cost thereof shall be included in unit rate quoted against the respective item of this schedule. (b) Rewinding of both HT & LT coils shall be measured and paid for separately under respective item of this schedule. (c) Transportation charges for transportation of transformer from site to workshop and after repair, workshop to site shall be borne by the contractor and cost thereof shall be deemed to be included in the unit rate quoted for this item. (d) The said transformer shall be repaired in reputed workshop as decided by the GE. (e) Note – Coil to be replaced shall have same number of turns, gauge insulation value matching with manufacturer’s design complete all as specified and directed.

Supply and replacement of HT coils made out of super enameled HT copper winding wire of transformers having capacity 250 to 400 KVA all as specified and directed

Supply and replacement of LT coils made out of super enameled LT copper strip of transformers having capacity 250 to 400 KVA all as specified and directed Note :- Coil to be replaced shall have same number of turns, gauge insulation value matching with manufacturer’s design.

Strip opening of transformer of capacity 250 TO 400 KVA, 11 KV /433 volts indoor /outdoor type of any make after unscrewing nuts & bolts, screws and connected accessories such as breather, conservator tank, temp gauge etc. for replacement of defective parts such as replacement of leaking gaskets, replacement of worn out/burnt out studs, checking and cleaning of contacts of tap changer and re-assembling the transformer after replacing the defective parts/repair complete all as directed. Notes : (i) Payment of defective parts to be replaced shall be measured and paid for separately under respective item of this schedule. (ii) The cost for replacement of packing material such as top gasket, shall deem to be included in the unit rate quoted by the contractor against this item (iii) The repair/strip opening of transformers shall be carried out at site of its installation without taking down/removal of transformer from the site of installation..

Supply only LT porcelain bushing and heat resistance gasket with brass/copper studs washer and rubber bush etc for Transformer of Cap up to 250 KVA.

Supply only LT porcelain bushing and heat resistance gasket with brass/copper studs washer and rubber bush etc for Transformer of Cap 400 KVA.

Supply only HT 11 KV porcelain bushing with brass/copper studs and gaskets and rubber bush etc for Transformer of Cap upto 400 KVA

Supply and filling up of fresh transformer oil as in topping up/levelling up after dehydration having dielectric strength not less than 60 KV at 2.5 mm gap conforming to IS -335/1993 all as specified and directed:

Overhauling/ servicing of HT VCB 400 to 630 Amps 11 KV of any make by carrying out following job:- (i)Taking out VCB trolly from the panel board. (ii)Removal of dirt,dust & carbon particles by air blower (iii)Cleaning of all moving & fixed contacts of VCB with dry cloth & CRC solution and greasing of moving contacts & gears. (iv)Checking and setting of VCB ON/OFF operation mechanism through TNC & push button. (v)Checking tightness of all control wires. (vi)Checking leakage in vacuum interrupter by Hi-Pot test (vii)Assembly of trolly and testing complete. Opening of VCB/Ring main unit) 11 KV of Capacity up to630 Amps for servicing, cleaning, tightening of loose mechanical mechanism, greasing,inspection of Busbar,CTs/PTs internal wiring of control panel ,indicators,measuring of IR value ,callibration of relays matching with 66 KV Grid replacement of unserviceable spare parts testing of tripping system and removing all type of dust and settled dirt by means of required T&P all as specified and directed by Engr-in-charge (spares shall be measured & paid separately) and testing complete all as specified and driected.

supply and fix change over switch 200 amp side operated change lever complete all as specified and directed by EIC.

S&F, triple pole, mechanically operated, mounted on insulator and steel frame, with operating mechanism worked from ground level , for current rating upto 400 amps complete all as specified and directed by EIC.

S&F, lightening arresters expulsion type complete with fittings, transmission class, discharge capacity 11000 amp complete all as specified and directed by EIC.

supply and lay and testing cable HT XLPE insulated confirming to IS:-7098 of 1985 screened PVC bedded, galvanised steel strip or wire armoured, electric cables(heavy duty) with stranded aluminium conductor 11000 volts grade, of size 3 core 95sqmm. Make:- Havells/Gloster,ICC,CCI, Paragon.

M&L for cable jointing kit for 11 KV(Earthed) grade cable for outdoor termination cold shrink type joint complete with jointing material and accessories suitable for 3 core XLPE armoured aluminium conductor cable of size 50 sqmm to 95 sqmm complete all as specified and directed by EIC. MAke:- Denson, M seal, Raychem

Material and labour of danger notice plate of 1.6 mm thick confirming to IS : 2551 of 1982 mild steel sheets vitreous enamelled white with letters figures and conventional skull and bones in signal red colour and fixed with MS clamps , bolts , and nuts of approved size for LT 25 cms x 20 cms .