GAS TURBINE PROTECTION AND INTERLOCK.doc

GAS TURBINE PROTECTION & INTERLOCK Parameters

Normal Value 2

L63QTX: Low Lube Oil Pressure Trip (0.56+/- 0.02 kg/cm ) L45FTX: Fire Indication Trip (315 OC) L86TGT: Generator Differential Lockout Trip. L4_RLYT: External Trip. L63ETH: Exhaust Pressure High Trip (508+/- 12.7 mmWC). L39VT: High Vibration Trip (25.4 mm/s). L2SFT: Start Up Fuel Flow Excessive. L12H_FLT: Loss of Protective HP Speed Signal Input Trip. L4CT: Customer Trip i.e. From DCS (For DD & GD interlock & HRSG Trip

1.75 – 1.85 kg/cm 70 – 90 mmWC 1.5 – 3.0 mm/s -

but DD not closed) L12HF: Control Speed Signal Loss HP Trip L12HFD_C: Control Speed Signal Trouble HP Trip. L12H_ACC: HP Excessive Acceleration Trip. L12_P: Protective Module Over speed trip. L12HHBLT: Over speed Bolt rip (Mechanical -111.5% 0F 5104 RPM) L12H: Electrical Over Speed (110% OF 5104 RPM). L3SFLT: Control System Trouble. L86GCVT: Gas C.V. Not Following Reference Trip. L40FBT: Off Base Skid Trouble Trip (Return Line Solenoid Valve Close And

5104 - 5115 5104 - 5115 -

Trip Value 2

0.56 508 25.4 5691 5614 -

Oil Temperature Raises To 76 OC)

Parameters

Normal Value

Trip Value

L4PRETX: Pre Ignition Trip Logic (During Start Up Only) L28FDX: Flame Detection Control (During Start Up Only) L63HL1L: Hydraulic Oil Trip Circuit Pressure Low (Liquid Fuel 1.4 +/- 0.07

3.5 – 4.0 kg/cm2

1.4

Kg/cm2) L63HG1L: Hydraulic Oil Trip Circuit Pressure Low (Gas Fuel 1.4 +/- 0.07

3.5 – 4.0 kg/cm2

1.4

Kg/cm2) L26QT: Lube Oil Temperature High (79.44 +/-1.6 OC). L28FDT: Loss Of Flame (Channel # 1 & # 2 OUT)

58 – 72 deg C All 4 channels

79.4

L4IGVT: IGV Control Trip. L30SPT5: Excessive Combustion Trip. L86CBT: Bleed Valve Position Trouble Trip. L86TFB: Exhaust Temperature Thermocouple Open Trip. L86TXT: Exhaust Over Temperature Trip (593 OC) L63FL2: Liquid Fuel Oil Pressure Low (0.42 Kg/cm 2 With Time Delay Of 20

480 – 525 deg C 3.5 – 4.5 kg/cm2

593 0.42

sec) L63TF-1H, 2AH, 2BH: Turbine Inlet Air Filter Excessive Pressure Drop (at 6 1 – 3 inch WC inch WC - Alarm & at 8 inch WC - Shutdown)

8 inch WC

L5E: Manual Trip HRSG PROTECTION : HRSG TRIP i.e. Diverter Damper & MS-31 will close if

following condition occurs: a) Drum Level Very High b) Drum Level Very Low c) GT Trip.

0 mm

+ 250 mm - 250 mm