BANGLADESH POWER DEVELOPMENT BOARD TENDER ... - BPDB

6.2.4 230 kV CURRENT TRENSFORMERS(1) TypeOutdoor, single phase, oil immersed with level indicator or gauge, N 2 gas sealedporcelain clad type, quadruplicate cores.(2) UseFor metering and protection(3) Ratingsa. Rated current- Primary :1200-800 A [to be at actualrequirement]- Secondary : 1-1-1-1 Ab. Rated insulation level-Lighting impulse withstand voltageFull wave (1.2 / 50 micro sec.): 1050 kV PEAK-Power frequency withstand voltage : (As per relevant IEC)KV for one min.c. Rated frequency :50 Hzd. Rated burden :60 VA for protection and:30 VA for measuring.e. Rated continuous thermal current :120%f. Short time current ratings-Thermal rating (r.m.s. for one sec.)-Dynamic rating (peak)g. Accuracy classes-For metering :0.2, n‹5-For protection: (As per relevant IEC)(4) Requirements for Design and Construction: (As per relevant IEC) KA:2.5 times the thermalratingsa. The current transformer shall be of oil immersed hermetically sealedstructure type.b. Internal conductor shall be adequately reinforced taking into account overcurrent intensity.c. The junction box with terminals shall be provided for the secondary circuitconnections.d. Each current transformer shall be equipped with terminal block of shortcircuiting type.e. Creepage distance of bushing shall not less than 25 mm / kV of phase tophase voltage. The glazing colour shall be of brown.Ghorasal 200 MW to 300 MW Gas Turbine Peaking Power Plant Project (Vol-2 of 3)63