WBPWD/EE/KNHED/e-NIQ-13/26-27

Dismantling of existing HT Gear in the exisisting Compact 1600 KVA Sub Station and all type of cable connection (incl. dismantling of glanding) maintaining normalcy as far as possible and keep it in a safe position as per direction of EIC (within the compound of R G Kar MC&H ) all complete. (Work should be completed within stipulated period of time as per availability period of Shut Down from Hospital Authority & direction of EIC)

Nominal system voltage: : 11 kV Highest system voltage: : 12 kV Rated normal continuous current: 630 A Number of phases: : 3 Frequency: : 50Hz Variation in frequency: : 50 ±3% Hz Type of earthing: : Solidly Earth Rated short time withstand current for 3s : 21kA Internal Arc Classification: IAC A FLR: 21 KA/3 sec Rated Peak withstand current: 52.5 KA Duration of Short Circuit : 3 Sec Power Frequency Withstand Voltage to Earth,Between Poles, & Across Opening Span: : 38 kV rms Lightning Impulse Withstand Voltage Phase-to-Phase & Phase-to- Earth:: : 95 kV peak Insulation Medium:SF6 Mechanical Endurance Class for specified operating sequence: M1 Electrical endurance class for specified operating sequence: E3

3 Nos. ring type, single core CTs in VCB for metering purposes. A similar arrangement shall be provided in each circuit breaker cable compartment to mount a 3 Nos. single-core, ring type CT for protection purposes.The CTs shall conform to IEC: 61869.CTs for Metering: Material : Epoxy resin cast/ Tape wound Burden : 2.5VA,Ratio : 100-50 /1 A,Accuracy Class : 0.5 CTs for Protection Material : Epoxy resin cast/ Tape wound,Burden : 2.5VA,Ratio : 100-50/1 A,Accuracy Class : 5P10

A 3 phase single or 3 nos. single phase potential transformers shall be provided. These may be housed in a separate air insulated PT Panel, directly connected to the RMU through main bus. The burden per transformer shall not be more than 50 VA and the voltage ratio shall be 11000/110 V .The accuracy class shall be 0.5.,HRC fuses shall be provided on the HV side. • Interconnection with bus PT shall be through bolted arrangement. • The PTs shall be of cast epoxy-resin construction, and they shall conform to IEC 60044-1.

The RMU shall be equipped with self-powered numerical relays(Communicable relays shall be with auxiliary power which shall be given from battery but the tripping shall be self-powered philosophy) communicable to trip the RMU circuit breakers. The protection relay’s auxiliary contacts shall be provided for hardwiring to the FRTU. The relay shall also interface with the FRTU via an RS 232/485 port in order to send, as a minimum, real-time readings using the MODBUS protocol. The numerical relay shall be self-powered and should provide Inverse Definite Minimum Time (IDMT) and Instantaneous protection characteristics. On this basis, the relay as a minimum shall provide: Phase Overcurrent Protection (50/51) Earth Fault Protection (50N/51N) The relay shall be provided with an input for remote tripping, which shall be realized via an electric output pulse even without presence of phase current. A flag indicator shall be installed for signaling the occurrence of trip conditions. It shall have three phase overcurrent elements and one earth fault element. IDMT trip current settings shall be 20-200% in steps of 1% for phase overcurrent and 20-80% in steps of 1% for earth fault.

Each RMU shall be fitted with a power supply, including batteries and battery charger, suitable for operating the motors of the On-load Isolators and Circuit Breakers. On this basis, the following operational specifications shall apply: The power supply unit shall conform to the following requirements: - Input: 230 V AC nominal from the RMU’s auxiliary power transformer allowing for possible variations from 190 to 300 V AC - Output: Stable 24 V DC. - Batteries: 24 V DC (2 Nos of 12 V DC each) The auxiliary power transformer shall be of suitable rating as per the load calculation and the Auxiliary power transformer inputs shall be equipped with surge protection devices in accordance with IEC 62305.

Instantaneous trip current settings shall be 100-3000% in steps of 100% for phase overcurrent and 100-1200% in steps of 100% for earth fault.Selectable IDMT curves shall be provided to include, for example, Normal Inverse, Very Inverse,Extreme Inverse, Long Time Inverse, and Definite Time. Separate curve settings for phase overcurrent and earth fault shall be supported. For IDMT delay multiplication, the Time Multiplier Setting (TMS) shall be adjustable from 0.01 to 0.1 in 0.01 steps. The relay shall also be provided with: Alphanumeric Liquid Crystal Display (LCD) for relay setting. Communications via a MODBUS RS232/RS485 port to provide the FRTU (and hence the DMS) with phase current measurements. It is also desirable that this same means of communication can be used by the FRTU to send setting and control commands to the relay. Parameter change capability i.e. password protected.

Supplying & laying of 6.6 KV (UE) Grade XLPE Aluminium conductor, PVC sheathed, armoured cable conforming to IS 7098, of earthed system of following size in existing masonary trench from CESC Gear to Consumer end Gear & Consumer end Gear to Transformer HT side [as per GS.] (Make:Polycab / RR /KEI/ Havells/ Gloster) 3 Core x 300 Sq.mm

Making heatshrinkable joints indoor type to the ends of the following XLPE HT cable at the transformer end as well as at the VCB ends supplying with necy. jointing kits (Raycham), sockets, sleeves, anti-corrossive paste, wires, solders, jointing compounds, rubber sheets etc. incl. supplying of necy. tools & tackeles for crimping the end sockets, soldering irons & making of glands at the both end of the cable as per directions of EIC 3 Core x 300 Sq.mm