Search results

We are facing an issue during the startup of one of our Gas Turbines Units. When the unit is on turning gear, Auxiliary lube oil pump (AC) is running and delivering normal pressure (around 6 Bars). However, during startup while unit is accelerating at 1500 RPM, the pump header pressure drops to...

We are facing an issue with exhaust TC in GE Frame 9E Gas Turbine unit with Mark 6e control system as follows: When unit is running, TTXD-6 reading fluctuation from normal value to minus value and accordingly Spread is increasing. Once we go for shutdown, TC value is showing steady value but...

In one of our units, GE Gas Turbine frame 9E, Controlled by Mark IV+, the SRV start hunting and P2 pressure is flactuating as well from firing till FSNL. After synchronization directly, SRV is not hunting and performing very normal. there are no other alarms or diagnostics. We have replaced the...

Why we need to have a trip "control" oil in frame 9 gas turbines? why we can't just control the hydrauilic oil directely by solenoid valve to block it in trip cases? Moreover, What is the use of trip oil pressure switches 63HG-1/2/3 protection? If we lose the trip oil, the dump / stop valve...

Dear All, We have a GE Gas Turbine unit with Mark IV+ control system. Recently, unit tripped 2 times without showing any alarm. We have an information system (from ABB) connected with Mark IV+ to work as historian and trender. We observed from there that all the parameters like NG pressure...

We have 5 Gas turbines GE Frame 9E. All of them are equipped with a fire protection system (CO2) to protect the turbine enclosure and Auxiliary compartment. However, the Generator enclosure is not having fire protection/ suppression system. Is it the same for all frame 9E machines and is there...

One of our units (Gas turbines) which is having Mark Vie control system (it was upgraded last year from Mark IV) is under shutdown now. Recently we did a small modification in logic (changed one input from used to unused only), then we made a download command then we got some diagnostics...

How is fuel changeover (from Gas to Liquid) happening in Frame 9E Gas turbines (GE) under Mark Vie control system? I know that a signal from gas pressure switch should initiate fuel changeover from NG to liquid fuel, but how is the logic working and which signal exactly is considered as...

Dear all, We have one problem in our control system Mark IV+ for GE frame 9 Gas turbines in DEWA- Dubai. I hope that somebody is having idea or can advise us. When turbine is in shutdown condition there was no alarm, but after giving start command the following alarms are appearing: *...

Hi everybody; I want to know the procedure of adding new analog input to the AIO module. We want to add new signal (4-20 ma) of level transmitter for monitoring purpose only. But it is not clear to me from Mark IV manual how to do the job. How to configure this input and range and which...

We have Speedtronic Mark IV+ control system for controlling GE Frame 9 Gas turbine machine. When I was stroking the Liquid fuel bypass valve after shutdown, I found that valve position is not going as per forcing voltage. for example if I give (+5 vdc) the valve is going only to 45 % closing...

Hi every body, My question is related more to designers than maintenance staff. But I want to share this with every body, may be somebody can help depending on his field experience. We have GE gas turbines Frame 9E controlled by mark IV control system. The over-speed protection is provided...

Hi every body We have GE gas turbine frame 9 dual fuel controlled by Mark IV system. The following alarm is coming frequently during normal running since long time and without relation with any particular situation: <R> voting mismatch (CSRGV) Also some other alarms are coming but not...

Hi Everyone I am working in a power plant where GE GTs are used, frame 9E , mark 4 DCS . I am trying to understand how the voting is done in mark 4 and I hope some one can answer my question. To explain my point , I am going to give an example: 3 pressure switches are used to measure...

always i read that speed ratio v/v control or maintain the gas pressure and control v/v controls the flow. Actually i don't know how to control flow without changing pressure. Or by other words, what is the difference between pressure regulation and flow regulation? In both cases we control how...

There are many temperature and level switches in gas turbine. Please if any one can explain the scientific and theoretical idea of operation of these two switches. I mean how these switches work and what is the physical phenomena behind it. thanks a lot

i want to understand the deep and detailed meaning of the master protective signal L4 in GE different control systems? i mean, what is the meaning of L4=1 or 0 , and what is the h/w or s/w behind its value. i know , this question may be so obvious , but forgive me guys... i still new in the...