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    Why Is the Bypass PCV Set to Override Close When Condenser Vacuum Is Lost?

    Hello, I have a question regarding the configuration of the bypass pressure control valve (PCV) in our combined cycle power plant. The HRSG bypass PCV is set to override close when the condenser vacuum pressure indicator (PI-0901) exceeds -0.5 Bar.g (-375 mmHg). Could someone explain why...
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    Inlet Guide Vane (IGV) Angle

    I'm curious about the reason for setting the angle of the IGV (Inlet Guide Vanes) from 34 degrees to 86 degrees in GE gas turbines. In particular, I don't understand the explanation that excessive combustion can occur when the IGV opens too much. It seems like the combustion temperature would...
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    Design Intent and Effects of Adding 0.2 bar to HP Steam Pressure when PCV is 95% Open in HRSG HP Bypass System

    Hello, I have a question regarding the control logic of the HRSG (Heat Recovery Steam Generator) HP (High Pressure) Bypass system. The current system implements the following logic: - When the HP Bypass PCV (Pressure Control Valve) opens 95% or more, the pressure setpoint is changed to a value...
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    Potential Issues from a Blown Fuse in One Phase of a VT for Generator Voltage Measurement

    If a fuse in one of the three phases breaks before reaching the VT (Voltage Transformer) used for measuring the generator terminal voltage, and this situation is left unattended for a long time, what issues could arise?
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    Why does the Extraction Turndown Valve open during low load conditions in a gas turbine?

    Those guys at GE must have made the manual terribly because it doesn't provide detailed explanations about not just the turndown valve, but other things as well. As far as I can tell, the reason the turndown valve opens at low load is to prevent surging. However, I don't understand why they...
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    Curious about the reason for the difference in lube oil tank differential pressure during gas turbine startup and shutdown.

    I'm curious about the reason for the difference in lube oil tank differential pressure during gas turbine startup and shutdown. During startup, the lube oil tank differential pressure is around 8 inches, but it decreases to 6 inches when stopped. I don't quite understand why there is a...
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    Curious about why the Discharge MOV opens 1 minute after starting the BFP

    Our company's BFP (Boiler Feed Pump) functions to suction from the LP (Low Pressure) Drum and send it to the HP (High Pressure) and IP (Intermediate Pressure) drums. When we start the BFP, the HP discharge small MOV (Motor-Operated Valve) opens, then the BFP starts, and after 1 minute, the HP...
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    I wonder why HP Leak off Steam is sent to the LP header

    I know that it is usually used for self sealing with HP Leak off Steam. However, in my power plant steam turbine, leak-off re-entry stop valve (LRSV) is open and sends HP Leak off Steam to the Lp Header side. Why is the hp leak off steam sent as Lp Header instead of using Self Sealing?
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