I am working on 6FA GE Gas Turbines as Control Room Engineer. It has ventilation air flow transmitters on Turbine Compartment (6 transmitters 3 on either sides) and DLN compartment (3 transmitters) inlet air.
Due to rainy season here from June to August, there is much fluctuation in air flow transmitters causing unit trips and normal shutdown several times. To avoid this situation, is it safe to force trip and normal shutdown logic?
Will it effect unit safety or operation capability even we know this fluctuation is due to weather effects?
>Will it effect unit safety or operation capability even we
>know this fluctuation is due to weather effects?
Yes. These transmitters are basically there to ensure there is ventilation air flowing so that if there are fuel leaks the concentration of combustible vapours will not be high enough that a spark or ignition source could cause a fire or explosion. Regardless of weather conditions.
The PROPER response to this situation is for someone to review the placement of the sensing lines (tubing lines) to the instruments to ensure there is no way for water to be ingested into the lines which can cause improper readings. The sensors (transmitters) should be mounted above (higher than) the openings of the sensing lines (tubing lines).
Forcing logic to prevent nuisance trips or shutdowns will only temporarily solve one problem: the problem of improper installation of the sensors and sensing lines. However, if there are fuel leak(s) while the logic is forced, there could be a problem with fire and/or explosion.
Hope this helps!