Gas turbine 2 x, 2 y jump machine bearing vibration disappeared

Gas turbine 2 x, 2 y jump machine 2018 - bearing vibration disappeared 07 - 12 PASCAL nouvellon event process: on January 28, 2016, 21 when 50 minutes and 56 seconds, # 7 of 309 mw gas turbine load, # 8 of 149 mw turbine load. # 7 combustion engine bearing vibration parameters are normal. On January 28, 2016, 21 when 50 minutes 58 seconds, # 7 CCGT 2 x, 2 y bearing vibration signal disappeared, cause the tripping, 33 seconds automatically return to normal. Cause analysis: after the unit trip, spot checks found as follows: 1, on-site inspection, found that # 2 vibration sensor wiring front-end for looseness. # 2 lateral bearing vibration sensor cable for multiple strands of wire, when being connected line nose, do not meet the quality requirements to access the front-end is easy to fall off. 2, 2 x, 2 y bearing vibration cable shielding wire for inspection, found on both ends of the cable is grounded. Within the TSI cabinets will be 2 x, 2 y bearing vibration sensor cable shielding wire removed, measuring the resistance of 8. 8Ω , in the middle of the field terminals in the cable shielding wire for measuring the resistance of 11. 8Ω That cable shielding grounding on both ends of the line, shielding jamming signal function failure. Caused by power plants that night in a thunderstorm center, # 7 combustion engine bearing vibration signal interference, # 7 CCGT 2 x, 2 y bearing vibration signal disappeared, gas turbine main protection conditions, 2 x, 2 y bearing vibration bad quality trigger tripping signals at the same time. Precautions: according to the combustion engine # 2 bearing vibration interference disappeared, according to standard practice to single-ended on vibration of cable shielding grounding, and organize the installation personnel to the scene, and modulate the other bearing vibration sensor cable shielding grounding of line inspection. Gas turbine 2 x, 2 y bearing vibration signal disappeared, cause the tripping, 33 seconds automatically return to normal.