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  1. A

    7FH2 Generator Cooler and Rated Load

    CSA, Thank you for the reply. I recalculated the MW and reached into the same answer as you had. I seems I made small error in my earlier calculations. But again, the rated load in the quote, it seems they meant the rated load for the generator. This is what I believe.
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    7FH2 Generator Cooler and Rated Load

    Greetings While I was reading GEK-107092d, I came across something not very clear. It talks about isolating one cooler (in case it has a failure) of the generator. Fortunately, we haven't had any cooler failures in the past. the quote is: "If a cooler leak is severe, the defective cooler...
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    False Start Drain Thermocouples

    Dears We have the same issue (still not solved). Our design (7FA) uses only one thermocouple "WWTD1-1A" (Type K) located inside the turbine compartment. The thermocouple is reading ambient temperature when the unit is shutdown. At high loads (like 140 MW), sometimes it is reading high (350...
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    Limit Switches on Compressor Bleed Valve

    Great answer from CSA as always. "The limit switches are usually wired to the normally open contacts, and the switches are actuated when the valves are closed--which means the contacts will be closed when the valves are closed.The inputs are usually NOT inverted, so l33cb1o and l33cb2o will...
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    Exhaust Temp Spread Trip after Selecting IGV Temp Match

    I forgot to include that also transition pieces, flow sleeves, and combustion liners were inspected.
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    Exhaust Temp Spread Trip after Selecting IGV Temp Match

    Dear CSA, After the borescope inspection of all cans. There were no major findings like burned fuel nozzle tip or clogged one. It seems the unit will go for tuning again (DLN 2.6). GE Engineering suspected an issue with pm 1 or pm 2 fuel nozzles since the IGV Matching ON is happening...
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    Exhaust Temp Spread Trip after Selecting IGV Temp Match

    Dear CSA, This unit will be under borescope inspection next week. I shall update you by then. Regards and thank you for your time
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    Gap Voltage for Axial Displacement and Zero Position

    Dear all During our outage, found gap voltage for Bently Nevada axial displacement probe was around 6.4 Vdc. I&C team adjusted this one to 10.2 Vdc since 10 Vdc is the recommended setting. After unit back to service, the axial displacement reading increased too much while the turbine was...
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    Intermittent Seismic Vibrations Increase at GE Frame 5 Turbine Compressor Casing

    The most suspected bearing to have oil coking is the bearing that is in the exhaust area (high temperature environment). The last time we had an oil coking, the vibration was cyclic. The vibration was detected by the proximity sensor. The problem was not detected by the seismic sensor to my...
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    Gas Turbine Mist Eliminator

    Dear bhavik The mist eliminator job is to remove the oil fine droplets from air. As the lube oil cools and lubricates the bearings, oil will get hot and oil vapor will be present in bearing housing. This oil vapor along with the air will mix and form "oily air". This oily air is drown to...
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    Checking for Leaks for Gas in the Turbine Compartment

    Dears, After we completed T&I for one of our units, three of the hazardous gas detectors read high when transferring from mode 4 to mode 6Q. The total number of detectors is eight. It seems there is really gas leak in the turbine compartment. Now I am asking if we could pressurize the pm4...
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    1st Stage Nozzle Melting at Trailing Edge

    Sorry for any confusion. All the wheel space data were taken at approximately 145 MW Load. The rated Load for our machines is 170 MW.
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    1st Stage Nozzle Melting at Trailing Edge

    Thank you for your reply 1) Advanced Gas Path (AGP) carried out at 32K running hours. Now the unit running hours is 52K hours. 2) I trended the wheelspace for three different units. All of them (including the unit that has this melting issue) are around 800 F at the first stage forward...
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    1st Stage Nozzle Melting at Trailing Edge

    Greetings all, During our T&I inspection, the turbine shell (casing) was removed for some job (not related to 1st stage nozzle). We found the 1st stage nozzles (S1N) at 9 & 6 clock positions have their trailing edge melted to some degree with TBC removed also from trailing edge. the leading...
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    Mark VI "Motor Running" Message

    Thank you CSA and Otised. That really helps! Regards
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    Mark VI "Motor Running" Message

    Greetings I have a small question regarding the signal l52qv1a "lower case" (description of the signal: # 1A Lube oil mist separator running ). the signal is defined in VCRC card and TBCI Board (contact input). Now my understating is that if the signal is "1" then the contactor of the...
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    Questions about MARK VI TMR

    Chiranjeevi and CSA, Thank you very much. I am taking my time reading the above posts. Again, Thank you
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    Questions about MARK VI TMR

    Greetings I am newbie in Control Systems. So please take my questions patiently and correct my understanding. From my understanding, The way "Redundant Input Signals" are handled is either High Select or SIFT Voting How the process of high select takes place ? Give me please a...
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    Frame 6 GT tripping on STOP/SPEED RATIO VALVE POS. ERROR TRIP

    Greetings CSA, Does your detailed reply apply to MARK VI TMR? Generally what input/output signals are voted and what are not voted?
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    Steam Turbine Start Up (Rolling) Procedure

    Otised, It is great to have you here. Thank you for taking the time to respond to each question. It was HELPFUL One thing I have to respectfully disagree with. The Reverse Flow refers to the direction of steam entering the HP Steam Turbine. During startup, there is a steam which enters the...
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