bids are invited for air circuit breaker voltage, rated: 690vac, rated current: 1000a (at 50 deg cen), no of poles: 3p, 1000 a, manually operated draw out type (mdo), having following specification: rated operational voltage at 50 hz: 690v, rated insulation voltage at 50 hz: 1000v, rated impulse withstand voltage: 12kv. utilisation category: b, breaking capacity: 50 ka (icu = ics = 100%) at 690 v, operating life: mech = 20000 operation, elect = 10000 operation. self-powered microprocessor based tripping arrangement having integral alpha numeric lcd display and adjustable l-t, s-t, i, g-t protection, single phasing protection.the acb shall provide the following mechanical and electrical indicators as features: contact position indicator (on / off), stored energy status indicator, connected / test / disconnected position, common trip indication, ready for closing indicator. control voltage = 230 vac, closing and trip coil voltage =230 vac, aux contacts: 4 no + 4 nc changed over or no+nc contact (minimum), applicable standards: iec 60947 part-ii, application: mcc at steel melting shop. total quantity : 3