标题: CFM56-7 7.B.N. Software Version [打印本页] 作者: 航空 时间: 2011-4-12 23:20:00 标题: CFM56-7 7.B.N. Software Version
作者: 航空 时间: 2011-4-12 23:20:39
CFM56-7 7.B.N. Software Version CFM56 Operators Conference – May 21 - 22, 2002 CFM Proprietary Data Unauthorized Disclosure Prohibited 2 CFM56-7 7BN Software • Key Functional Changes - High altitude ratings for 737-600 and 737-700 - Modified PS3 lower range limit - EGT trim logic simplification - Improved VSV & VBV selection logic - Improved start-lever selection logic - Modification To VBV fault disagree threshold - Revised N1 Trim washout function - Correction to EGT redline indication during airstarting - BSV and MSV solenoid driver logic CFM56 Operators Conference – May 21 - 22, 2002 CFM Proprietary Data Unauthorized Disclosure Prohibited 3 7.B.N Change List • High Altitude Rating(s) for 737-600 and 737-700 - Addition of two new ratings - 7B22/B2 (for -600) 7B26/B2 (for -700) - Takeoff and Climb same as current 7B22 (for -600) and 7B24 (for -700) - Emergency Over Boost (EOB) faired between 7B22 and 7B27B1 (for -600) and 7B26 and 7B27B1 (for -700) - Max Continuous faired between 7B22 and 7B26 (for -600) and 7B24 and 7B26 (for - 700) - Input Selection (New ID Plug Rating) - Maintenance Logic (FDP and MMP) • Ps3 Signal Selection - Modification to range checking to improve detection of disconnected Ps3 line • EGT Trim Logic - Simplification to trim logic to aid in EGT trending - Currently two EGT trim levels exist (takeoff and EOB) - Proposed logic ties EGT trim to nameplate allowing for one EGT trim level - Elimination of DAC Shunt for 7B27B1 Rating CFM56 Operators Conference – May 21 - 22, 2002 CFM Proprietary Data Unauthorized Disclosure Prohibited 4 • VSV/VBV Selection logic - Improvement to current selection logic robustness by using a fault history similar to FMV selection • Start Lever Selection Logic - Current logic prevents engine starts with single point failure in start lever - DEU 1 and DEU 2 discrete signals are not fully independent (share same start lever relay) - New logic to use the two analog EEC reset discretes and two igniter voltages in a 2 out of 4 or 3 out of 4 voting scheme • VBV Disagree Fault Tolerance - Disagree fault threshold to be changed from a constant 4 degrees to a variable as a function of VBV door position - Maintain current 4 degrees threshold at high power - Increase threshold at low power to prevent inadvertent VBV disgree faults from being set 7.B.N Change List (cont.) CFM56 Operators Conference – May 21 - 22, 2002 CFM Proprietary Data Unauthorized Disclosure Prohibited 5 7.B.N Change List (cont.) • N1 trim washout function - Modify washout function so that trim is ramped out between 103.5% and 103.7% to eliminate ‘flat’ in indicated N1 • New throttle interpolation curves for new high altitude ratings - New interpolation points used with new ratings in order to maintain thrust sensitivity requirements • Modification to quick windmill relight EGT redline inhibit logic - Latches quick windmill relight timer threshold - Prevents EGT redline inhibit once start determined not to be a quick windmill relight - Addresses potential for erroneous redline indication during over temperature events • Modification to burner staging valve and main staging valve driver logic - When opening the MSV Channel-A and Channel-B will drive the solenoid for two seconds (DAC only) - When closing the BSV channel-a and channel-b will drive the solenoid for two seconds (SAC only) - After two seconds the channel-in-control will keep the solenoid energized until required to de-energize作者: kinran 时间: 2011-6-4 23:32:50
