MAINTENANCE OF 132 KV GIS SYSTEM AND OTHER ALLIED WORKS AT MRS AT NAVAL DOCKYARD, VISAKHAPATNAM UNDER GE (I) DM VISAKHAPATNAM

Amount

M&L for M2 maintenance of 132 KV GIS system by OEM ie service enginer of GE T&D India Ltd (formerly Areva) and submission of following service and testing complete report all as specified and dircted :- (a) Gas Test for all the bay compartment (Dew point measurement SF6 purity check {% measurement} Alarm check for density switches optional Gas leak test. (b) Circuit Breaker mechanical test :- Visual inspection of spring operated mechanism mannually on/off spring-operated mechanism optical indicator( spring on/off) position check. (c) Electrical test :- Breaker timing test, Auxiliary contact change over position, check spring charge motor current measureas & time measurement, heater current measurement.

(d) Disconnector/Earthing switches mechanical test :- Mannually on/off with hand crank optical position indication check for change over, insulated earth switch external earthing link installation & tightness check. (e) Contact resistance check :- Test as per circuit proposed during commissioning. (f) Current & voltage transformer/Local control cubicle :- Terminal tightness check and wquipment operational and alram test. Note :- Required working tools will be provided by GE T&D India Ltd .

Maintenance of existing earth pits having good resistance value by cleaning/removing debris from earth pit chamber, wild vegitations/grassess around pits, cleaning of funnel complete all as specified and directed.

M & L for earth enhancing compound up to earth pit GL to reduce the soil resistivity as per clause 14.5b of IEEE 80:2000 (latest Edition) of make Earthcon upto the ground complete all as specified and directed.

M&L copper strip 32 x 6mm with saddle and fixing screws, including insulating block for connection of pit to bldg test point complete all as specified and directed.

M&L copper strip 75 x 10mm with saddle and fixing screws, including insulating block for connection of pit to bldg test point complete all as specified and directed by Eng-in-charge.

M & L for casting Chemical earth pits with Pipe in Pipe technology 50 mm Cu bonded , 200 microns, 3 Mtr Long Earth Electrode targeted/ achieving individual earthpit result from 1.5 ohms upto maximum of 5.0 ohms for each individual pit and by maintaining of expected Grid value of 0.20 ohms but less than 0.5 ohm for grid earth pits as in around individual technical building with the following items, specifications and testing complete for each pit complete all as specified and directed. (i) Boring 300 mm dia of earth pit in soft and loose soil upto the depth of not less than 2.5 m deep below ground level by means of any method i.e boring/ digging including removal of excavated material to a distance of 50 m as directed by Engr-in-charge in each pit. (ii) Filling the each bore hole with 10 kg thick compacted layer of earth enhancing compound to reduce the soil resistivity as per Clause 14.5d of IEEE 80:2000 (latest Edition) of make Terec+ as per manufacturers specifications.

iii) Placing of 3 m length of 50mm dia of copper bonded pipe-in-pipe earth electrode with welded copper plate 38mmx200mm of 12mm thick on top. The earth rod should be placed at centre of each bore hole/earth pit with minimum of 10 kg inserted in to Terec+ layer (iv) Back filling with earth enhancing compound up to earth pit GL to reduce the soil resistivity as per clause 14.5b of IEEE 80:2000 (latest Edition) of make Earthcon upto the ground. (v) Connecting/Jointing/brace welding each electrode of earth pit serially with copper earthing strip 25X3 mm with minimum 3 m distance between two earth pits buried below GL in trench filled with earth enhancing compound to reduce the soil resistivity as per Clause 14.5b of IEEE 80:2000 (latest edition) by enhancing its ionic properties, dispersion properties, hygroscopic properties, expansion properties, diffusion properties etc, incl earth excavation complete all as directed by Eng-in-charge.

(vi) Placing 500X500X250 mm HDPE earth pit cover (IEC 62561-5) flushed with ground placed over 100mm thick PCC (1:3:6 Type I) of size 550 x 550 mm including required earth excavation, refilling and packing. The earth pit cover should be UV stabilized, lockable jam free lid, stackable design, resistant to substances including petrol oil, diesel, bitumen and concrete etc vii) The quoted rate is deemed to be inclusive of necessary removal of excavated soil to a distance of 50 mtr as directed by the Engr-in-Charge. viii) Any other requirement if desired by the Engr-in-Charge as per site conditions shall be provided by the contractor without any extra cost. Note: a) The earth pits should have a minimum distance of 3m from each other and a minimum distance of 2m from building walls b) If grid value is found less than 0.5 ohms then the contractor will re-execute earth pits or put addl pit with no extra cost to the Govt.

Power engineering Associates

Jessica Engineering Works