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KAHALGAON STAGE-II 3x500 MW
INDEXSG Side PAGE
NO.1. Master fuel trip 12. Unit purge logic 13 Light oil valve 24 Heavy oil valve 25 Mills 36 Raw Coal feeder 67 ID fan 78 FD fan 9
9 PA fan 1110 BCW pumps 1311 Secondary pre heater 1412 Primary air heater 1613 HPBP 1814 Scanner fan 2015 Seal Air fan 2116 LDO HFO pump 2217 ERV 23
TG Side
1 Turbine Protection 242 Turbine lub oil system 253 Turbine HPCF System 284 Evacuation system 325 Turbine fire protection 366 EHTC 387 GENERATOR AUXLIARIES 418 TDBFP 479 MDBFP 5410 CEP 5911 ACW PUMP 6112 ECW PUMP 6313 LPBP GSPC 6514 AUX PRDS 6615 LP HEATERS 7116 HP HEATERS 7417 DEAERATOR 8018 CW PUMP 8219 CONDENSATE TRANSFER SYSTEM 85
20 LEVEL SETTINGS 86
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 1
1. MASTER FUEL TRIP
1. Both ID Fan OFF
2. Both FD Fan OFF
3. Water Wall Circulation Incorrect
4. Both EPB-1,2 Pressed
5. Furnace Pressure Very Low < -175 mm WC
6. Furnace Pressure Very High > 150 mm WC
7. Drum LVL V High TD 10 Sec > 250 mm above NWL
8. Drum LVL V Low TD 5 Sec < -375 mm below NWL
9. Air Flow < 30 % < 600 TPH
10. Loss Of Reheater Protection ( TD 10 Sec)
11. Unit 24 V DC Not Available
12. Unit 220 V DC Not Available ( TD 2 Sec)
13. Less Than FB & Loss of AC in any Elevation in service
14. Unit Flame Failure Trip
15. Loss Of All Fuel Trip
16. All Secondary Air Heaters Off
17. All Boiler Feed Pumps Tripped TD 10 Sec
18. MFT network failure
19. Soft EPB trip
2. UNIT PURGE LOGIC
1 MFT DPUs unfreezed
2 No Boiler Trip Conditions In all the Three Channels
3 Both PA Fans Off.
4 HOTV Closed.
5 All Elevations HONV Closed.
6 LOTV Closed
7 EL AB All LONV Closed.
8 All Feeders Off.
9 All Hot Air Gates Closed.
10 All Elevations Show No Flame.
11 All Auxiliary Air Dampers Modulating.
12 Air Flow < 40% & > 30 %
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 2
3. LIGHT OIL TRIP VALVE
3.1 OPENING PERMISSIVES:
1. Unit 24 V DC Power Available.
2. No Close PB Command3. LO Supply Pressure OK > 15 Kg/cm2
4. EL AB All LONV Closed
5. No Auto Closing Conditions Present.
6. NO MFT
3.2 AUTO CLOSING CONDITIONS:
1. LO Hdr Pr V Low (< 3 Kg/cm2) & EL AB any LONV not closed(
TD 5 Sec) OR
2. Atomising Air Pr. V Low < 3.5 Kg/cm2 ( TD 5 Sec) & EL AB any
LONV not closed & No LO Start/Stop in EL AB OR
3. Master Fuel Trip Operated. 2/3 Logic OR
4. Loss of unit +24V power supply
4.0 EQUIPMENT: HEAVY OIL TRIP VALVE
4.1 OPENING PERMISSIVE:
1. HO Supply Pressure Adequate > 21.2 Kg/cm2 &
2. HO Supply Temperature Adequate > 110 C &
3. No MFT &
4. All Elevation HONV Closed &
5. No Closing Command from APS or MMI &
6. No Auto Closing Conditions
7. Above Conditions Or condition below 8-9 & 24 V Power available
8. HO Recirculation Valve Open &9. No Auto OR Manual close commands.
4.2 AUTO CLOSING CONDITIONS:
1. HO Hdr Temp V Low & Any HONV not closed
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 3
5. EQUIPMENT : MILLS
5.1 MILL READY CONDITIONS :
1. No Pulv Unsuccessful elevation start2. Bunker Outlet Gate open
3. Feeder Inlet Gate open
4. Mill Discharge Valve open
5. Mill start permit from PLOS ( See Conditions Below)
6. Mill Outlet temp not high < 90 C
7. Cold Air Gate open
8. Tramp Iron Hopper Valve open
9. Mill/ Oil Elevation Start Permit
10. No MILL Trip
11. Primary Air Permit Yes
12. All Burner Isolation Gates open
5.2 MILL START PERMIT FROM PLOS:
1. Any Lub Oil Pump ON
2. Sump / Lube Oil Temperature not high < 80 O C
3. LOP discharge pressure not low > 3.5 Kg/cm2
4. Lube Oil Filter DP Not High < 1.5 Kg/cm2
5. Sump Oil Level Adequate (10mm below CL)
6. Lube Oil Pressure Not Very Low > 3 Kg/cm2
5.3 MILL START PERMISSIVES:
1. MILL Ready Conditions As Above
2. SA HDR/ Pulv Bowl DP Adequate > 350 mm WC3. MILL Motor Switchgear Available
4. MILL Status Off & Igntion Permit Available
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 4
MILL PROTECTIONS :
1. Motor Winding Temp V high (TD 5 Sec) > 130 0 C
2. Motor Brg Temp V high ( TD 5 Sec ) > 90 0 C
3. Mill Brg Temp Very High ( TD 5 Sec ) > 90 0 C4. Mill Trip From PLOS
5. Pulv H/W Trip from MCC
6. Pulv on & SA HDR/Bowl DP low( TD 1 Min)< 200 mm WC
7. MFT Acted
8. Pulv. Ignition support required & permit NA
9. Pulv. command On and failed to start TD 10 Sec
10. Pulv. discharge valve not open
11. Any burner isolating gates not open
12. Loss of primary air ( See Conditions Below)
13. PA Trip.( TD J0,H2,G4,F6,E8 Sec)
14. Loss of elevation +24 V power supply
15. EPB pressed
5.4 MILL TRIP FROM PLOS :
1. MILL On and LO Temp high (TD 60 Min)> 80 0 C
2. MILL On & Both Lube Oil Pumps off ( TD 2 Sec)3. LO Pres V low & LOP In Service (TD 10 Sec)< 3 Ksc
4. Lube oil level very low.
5.5 LOSS OF PRIMARY AIR CONDITIONS (TRIP):
1. PA HDR Pressure very low < 500 mm WC Or
2. All PA or FD Fans off and fast cut back ONOr
3. PA HDR pressure low (TD 5 Sec) < 625 mm WC
5.6 START PERMISSIVES FOR LOP:
1. Lube Oil Level Adequate
2. No Lube Oil Trip Command
5.7 STOP PERMISSIVES FOR LOP:
1. MILL off > 5 min
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 5
5.8 STANDBY LOP AUTO START CONDITIONS:
1. Lube oil pump running & pressure low < 3.5 kg/cm2
2. Lube oil pump fail to start ( TD 5 Sec)
DESCRIPTION OF PA TRIP : On fast cut back
(Applicable to Mills J,H,G,F,E Progressive time Delay of 2 sec
starting from Mill J whose trip is instantaneous)
1. 5 Or More MILL On & any One Of the Following
2. Any FD Fan Off
3. Any PA Fan Off
4. Loss of BFP - at least 2 BFPs - OFF
5. Loss Of SAH - at least 1 SAH - OFF
6. BCW pumping Not O.K - 2 P/Ps ON & DP 500 mm WC &
2. [All PA or FD Fans off and Any Pulv On and No fast cut back OR
Any PA fan ON and More than 5 Mills not ON] &3. PA HDR pressure low (TD 5 Sec) > 625 mm WC
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 6
6. RAW COAL FEEDER
6.1 START PERMISSIVES:
1. Feeder Switch In Remote &2. MFT Not Acted &
3. Mill Outlet Temp Not low > 55 0 C &
4. Mill Status On &
5. Feeder Seal Air Valve Open &
6. Fdr Speed Min &
7. Mill Ready &
8. Feeder Outlet Gate Open &
9. Mill Ignition Permit Available or mill ignition support not required
6.2 PROTECTIONS:
1. Feeder Switch Not In Remote Or
2. MFT Operated Or
3. Mill Outlet Temp Low < 55 Deg C Or
4. Mill Status Off Or
5. Auto/Manual Stop Command Or
6. Fdr Seal Air valve not open Or7. Fdr On > 5 sec & no coal on belt & Mill Motor current Not low Or
8. Pulv Ignition Permit Not available and Ignition Support Required
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 7
7. ID FAN
7.1 START PERMISSIVES FOR VFD CH-1:
1. VFD CH-1 No Fault
2. VFD Source Breaker On
3. No VFD alarm persisting
4. VFD CH-1 Ready
5. VFD Start Permissive available.
6. VFD CH-2 On Or 7,8 Below
7. Fan Control Damper Posn Min
8. Fan Inlet & Outlet Gates Closed
9. Fan Either Lube Oil Pumps On.
10. Fan Lube Oil Pressure > 0.8 Kg/cm2
11. Fan Motor Temp Not high < 85 o C
12. Fan Brg. Temp Not high < 90 o C
13. Fan Motor & Exciter Winding Temp Not high < 125 o C
14. Fan VFD Aux Supply OK
15. FG Path Available or Other ID Fan On
16. Lube Oil Temp Aft Cooler Not high < 50 o C
17. ID Fan-B Lub oil tank level > MIN
7.2 PROTECTIONS FOR VFD CH-1 :
1. VFD Ch-1 FAULT
2. ID Fan-B Ch-1 SRC Breaker Elect Trip
3. Mtr Brg temp V HI>=90 deg C
4. FAN Brg temp V HI, >=82 deg C
5. Mtr Wdg temp V HI, >=130 deg C
6. MTR Brg Vibration V HI, >=7.1 rms mm/sec TD-05 SEC
7. FAN Brg Vibration V HI, >=19.8 0-p mm/sec TD-05 SEC
8. Exciter Wdg temp V HI, >=130 deg C
9. IDF-A Post Purge TRIP
10. ID Fan-B ON for 30 sec & Disch damper CLSD, TD-05 sec
11. ID Fan-B ON for 30 sec & I/L gate CLSD, TD-05 sec
12. Both ID and both FD ON & FD-B trips
13. EPB pressed
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 8
7.3. ID FAN LOP
1 ON PERMISSIVE:
1. Lub oil tank level not low.
2. No MCC disturbance
2 OFF PERMISSIVE:
1. ID Fan off OR
2. Other LOP on and Lube oil pressure > 0.8 Kg/cm2
3 AUTO ON:
1. ID Fan On & LOP-B trips
2. ID fan ON and Lube oil pressure < 0.6 Kg/cm2
3. LOP-B ON and Lube oil pressure < 0.6 Kg/cm2
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 9
8. FD FAN
8.0.1 START PERMISSIVES:
1. Fan L O Pressure Adequate > 0.8 Kg/cm2
2. Fan Motor Winding Temp Not high < 125 o C
3. Fan Brg Temp Not high < 90 o C
4. Fan Motor Brg Temp Not high < 85 o C
5. Fan Control Oil Pressure Adequate > 8 Kg/cm2
6. Fan Control Damper Position Minimum
7. Fan Outlet Damper Closed
8. Either LOP on
9. FAN Switchgear Available
10. Lub Oil tank level not MIN
11. Fan Lube Oil Cooler O/L Temp. Not High < 50 o C
12. Both ID Fans On & I/L, O/L gates OPEN
13. Either ID Fan On & I/L, O/L gates OPEN & Other FD Fan Off
8.0.2 PROTECTIONS
1. Fan On & O/L Damper Closed (TD 30 Sec)
2. Both FD Fans On & both ID fans ON & ID Fan-B OFF3. Both ID Fans OFF
4. Post Purge Trip From FSSS
5. Fan Brg Temp Very High ( TD 5 Sec)> 110 o C
6. Motor Brg Temp Very High ( TD 5 Sec )> 90 o C
7. Fan Motor Winding Temp V High( TD 5 Sec)> 130 o C
8. Fan/ Motor Vibration V High TD 05 Sec)> 7.1 rms mm/s /19.8 p-p
mm/s
9. EPB pressed
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 10
8.1 EQUIPMENT: FD FAN LOP
ON PERMISSIVE:
1. Lub oil tank level not low.
OFF PERMISSIVE:
1. FD Fan off OR
2. Other LOP on and conditions at 3-4 below
3. Lube oil pressure > 0.8 Kg/cm2 &
4. Control Oil Pressure > 8 Kg/cm2
AUTO ON:
1. FD Fan On & LOP-B trips
2. FD fan ON and (Lub oil pr < 0.6 Kg/cm2 OR cntrl oil pr < 6
kg/cm2)
3. LOP-B ON and (Lube oil pr < 0.6 Kg/cm2 OR control oil Pr < 6
kg/cm2)
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 11
9 PA FAN
1. START PERMISSIVES:
1. Motor Winding temperature Not High < 125 Deg C
2. Fan Bearing Temperature Not High < 85 Deg C
3. Motor Bearing temperature Not High < 90 Deg C
4. Lub Oil Pressure Adequate > 0.8 ata
5. Control Oil Pressure Adequate > 8 ata
6. Lub Oil Cooler O/L Temperature Not High < 50 Deg C
7. Any Lub Oil Pump On
8. Lub Oil Tank Level Not Low
9. Blade Pitch Position Min < 2 %
10. Fan O/L Damper Closed
11. Both FDs On OR [Any FD ON & PA-B OFF]
12. Both PAPH ON & Air path available OR [Any PAPH ON &
Air path available & PA-B OFF]
13. PA fan start permissible available OR Other pa fan ON
2 PROTECTIONS:
1. MFT Operated2. Temperature V. Hi [ DE & NDE] >=110 deg C
3. Brg temp V HI >=90 deg C
4. Mtr Wdg temp V HI >=130 deg C
5. MTR Brg Vibration V HI [RMS] >=7.1 rms mm/sec TD-05 SEC
6. FAN Brg Vibration V HI[Peak] >=19.8 0-p mm/sec TD-05 SEC
7. Both FD Fans Off
8. PA Fan-B On & O/L Damper Closed TD 35 SEC
9. EPB pressed
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 12
9.1 PA FAN LOP
ON PERMISSIVE:
1. Lub oil tank level not low.
OFF PERMISSIVE:
1. PA Fan off OR
2. Other LOP on and conditions at 3-4 below
3. Lube oil pressure OK > 0.8 Kg/cm2 &
4. Control Oil Pressure OK > 8 Kg/cm2
OFF PERMISSIVE:
1. PA Fan On & LOP-B trips
2. PA fan ON and (Lube oil pr < 0.6 Kg/cm2 OR control oil pr < 6
kg/cm2)
3. LOP-B ON and (Lube oil pr < 0.6 Kg/cm2 OR control oil pr < 6
kg/cm2)
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 13
10 EQUIPMENT: BOILER CIRCULATING PUMP
10.1 START PERMISSIVE:
1. BCW PUMP-C Disch. Valve-1 OPEN
2. BCW PUMP-C Disch. Valve-2 OPEN
3. BCW PUMP-C Cooling water flow Not low >=32 gpm
4. BCW PUMP-C motor cavity Temp. O.K >2o C & 60C TD 5 Sec
2. Discharge V/V Stem-1 Not Open
3. Discharge V/V Stem-2 Not Open
10.3 BCW CW BOOSTER P/P
AUTO START CONDITIONS:
1. Running Other Pump Tripped. Or
2. Other P/P On & Discharge Pressure Low< 3.5 Kg/cm2
3. MCC Disturbance Not Present
4. Local Intervention Not There
OFF PERMISSIVES:1. Boiler Not Working Or
2. Other Pump On & Discharge Pressure Not Low.
Auto OFF:
1. Overhead tank level high
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 14
11 EQUIPMENT : SECONDARY AIR HEATER.
START PERMISSIVES : Electrical Motor
1. Guide Bearing oil temp Not high < 70 o C
2. Support Bearing oil temp Not high < 70 o C
START PERMISSIVES : Air Motor
1. Thrust Brg Temp Not high < 70 o C
2. Guide Brg Temp Not high < 70 o C
3. Electrical motor OFF
INTERLOCKS :
AUTO ON:
If SAH Electric Motor Trips Air Motor takes start in auto in 1.5 sec
AUTO OFF:
If SAH Electric Motor takes start , Air Motor Stops in auto.
13.4 Air Motor running status from pr switch (setting 3.0 kg)
13.5 Fire sensing alarm (setting 450C)
11.1 SAH GUIDE BEARING LOP
START PERMISSIVES:
1. MCC Not Disturbed.
AUTO ON:
1. Other LOP OFF and start command
2. LOP-B On & LUb oil flow low (
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 15
11.2 SAH SUPPORT BEARING LOP
START PERMISSIVES:
1. Guide Bearing Temperature not low > 35 o C
2. No Auto Off Command3. MCC Not Disturbed.
AUTO ON:
1. Other LOP OFF and start command
2. LOP-B On & LUb oil flow low (
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 16
12 PRIMARY AIR HEATER.
START PERMISSIVES : Electrical Motor
1. Guide Bearing oil temp Not high < 70 o C
2. Support Bearing oil temp Not high < 70 o C
3. No auto Off Command from SGC
4. Electrical motor MCC Not Disturbed.
START PERMISSIVES : Air Motor
1. Thrust Brg Temp Not high < 70 o C
2. Guide Brg Temp Not high < 70 o C
INTERLOCKS :
AUTO ON:
If SAH Electric Motor Trips Air Motor takes start in auto in 1.5 sec
AUTO OFF:
If SAH Electric Motor takes start , Air Motor Stops in auto.
19.4 Air Motor running status from pr switch (setting 3.0 kg)
19.5 Fire sensing alarm (setting 450C)
12.1 PAH GUIDE BEARING LOP
START PERMISSIVES:
1. Guide Bearing Temperature not low > 35 o C
2. No Auto Off Command
3. MCC Not Disturbed.
AUTO ON:
1. Other LOP OFF and start command
2. LOP-B On & LUb oil flow low (
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 17
AUTO OFF:
1. Bearing temp < 35C
2. OFF CMD
12.2 PAH SUPPORT BEARING LOP
START PERMISSIVES:
1. Guide Bearing Temperature not low > 35 o C
2. No Auto Off Command
3. MCC Not Disturbed.
AUTO ON:
1. Other LOP OFF and start command
2. LOP-B On & LUb oil flow low (
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 18
13 HP BYPASS SYSTEM
13.1 OIL SUPPLY PUMP FOR HP BYPASS
1. Pump off: >150 Kg/cm2
2. Pump on: 160 Kg/cm2
4. Pressure too low: 8 Kg/cm2
6. Any one of the above & No Priority close
2 BP VALVE PRIORITY CLOSE CONDITIONS:
1. Condenser vacuum low < 0.6 Kg/cm2 OR
2. Selected Downstream temp signal v high > 480 0 C
3 BP VALVE AUTO BLOCKING CONDITIONS:
1. BP Valve Priority Close Command OR
2. BP Valve Position Transmitter failed. OR3. OSU-1 & OSU-2 Oil Pressure Very Low. OR
4. MSL PR TX Disturbed.
4 BD VALVE AUTO OPEN CONDITIONS:
1. BP Valve PI demand > 2% OR
2. BP-1 OR BP-2 Valve open > 2%
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 19
5 BD VALVE AUTO CLOSE CONDITIONS:
1. No auto open command AND
2. BD valve LS FB Open.
6 BPE VALVE AUTO BLOCKING CONDITIONS:
1. BPE both DS Temp Signal disturbed
2. BPE Valve Position TX failed
3. BP-1 Auto Command blocking yes
4. BPE-1 Temp TX Deviation high
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 20
14 EQUIPMENT: AC SCANNER AIR FAN
AUTO START CONDITIONS:
1. No MFT & Scan - Furnace DP Low( TD 10 Sec) < 150 mm WC
2. ON Order from APS/SGC
3. Scanner Air Fan B (DC fan) did not take start within 5 sec. after
receiving the start command
PERMISSIVE FOR OFF:
1. Either MFT Operated or Scan Duct To Furnace DP Not Low &
2. Both Scanner fans Running Or (MFT & Either Scanner fans On)
PROTECTION OFF:
1. If both the fans did not take start within 5 sec. Off command is
generated, OFF command will be issued to the fan after 10
sec.Either MFT Operated or Scan Duct To Furnace DP Not Low
&
14.1 DC SCANNER AIR FAN
AUTO START CONDITIONS:
1. No MFT & Scan - Furnace DP Low( TD 10 Sec) < 150 mm WC2. ON Order from APS/SGC
3. Scanner Air Fan A (AC fan) did not take start within 5 sec. after
receiving the start command
PERMISSIVE FOR OFF:
1. Either MFT Operated or Scan Duct To Furnace DP Not Low &
2. Both Scanner fans Running Or (MFT & Either Scanner fans On)
PROTECTION OFF:
1. If both the fans did not take start within 5 sec. Off command is
generated, OFF command will be issued to the fan after 10
sec.Either MFT Operated or Scan Duct To Furnace DP Not Low
&
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 21
15 EQUIPMENT: SEAL AIR FAN
AUTO START CONDITIONS:
Either PA Fan On & SA HDR/CA Duct DP Low(TD 10 Sec) < 100 mm
WC
PROTECTION OFF CONDITIONS:
1. Both fan Started TD 10 Sec Or
2. Fan Breaker Tripped On Overload Or
3. Both PA Fans Off ( TD 15 Sec)
PERMISSIVE OFF CONDITIONS:
1. Both Fans Running &
2. Scan-Furnace DP Not Low
3. VPC/Pushbutton Off Command
START PERMISSIVES:
Outlet Damper LS Feedback Closed
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 22
16. LDO PUMP
START PERMISSIVE
1) MCC not disturbed
2) Pump not running3) Suction pressure not low (>-0.1 ksc)
4) LDO Storage tank level not very low
TRIP PROTECTION
1) Pump overload
2) LDO tank level very low
3) LDO suction pressure before strainer low (-0.1 ksc)
4) LDO Storage tank level not very low
TRIP PROTECTION
1) Pump overload
2) LDO tank level very low
3) LDO suction pressure before strainer low (
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 23
17. ERV Settings
Set pressure KSGSl.
No.
Location Valve Tag NO
Open Close
1 MS LINE (L) SV 9 185.5 180.3
2 MS LINE (L SV 10 185.5 180.33 MS LINE (R) SV11 186.6 180.64 MS LINE (R) SV12 186.6 180.65 MS LINE (R) SV13 186.6 180.66 RH LINE (L) SV 22 48.0 46.67 RH LINE (L) SV23 48.0 46.68 RH LINE (R) SV24 48.5 47.19 RH LINE (R) SV25 48.5 47.1
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 24
1. TURBINE PROTECTIONS
Sr.
No.
Description Alarm Set
point
Trip set point
1) TG Lub oil pressure very low (< 4.5ksc) (< 1.2 ksc)
2) Axial shift high (+/-0.5 mm) (+/- 1.0mm)
3) HP exhaust temp. high (> 480 degc) (> 500 degc)
4) Condenser vaccum low(VSP) --- ---
5) Condenser vaccum low(FSP) AND
Turbine speed > 240 rpm
(> -0.8 ksc) (> -0.7 ksc)
6) HP casing top/btm DT high AND Load
>100MW
(> 90 degc) (> 100 degc)
7) IP casing front top/ btm DT high AND
Load >100MW
(> 90 degc) (> 45 degc)
8) IP casing rear top/ btm DT high AND
Load >100MW
(> 90 degc) (> 45 degc)
9) MFT S/W & H/W --- ---
10) Generator electrical protection S/W &
H/W
--- ---
11) Liquid in Generator Main leads top ----- (> 90 mm)
12) Cold gas temp after cooler A&B high (> 55 degc) (> 60 degc)
13) Cold gas temp after cooler C&D high (> 55 degc) (> 60 degc)
14) Primary water temp after cooler high (> 55 degc) (> 60 degc)15) Seal oil temp after cooler high AS (> 50 degc) (> 60 degc)
16) Hot air main exciter temp high (> 75 degc) (> 80 degc
17) Stator winding flow very low (< 48 tph) (< 54 tph)
18) Stator Main bushing R flow low (< 1.4 tph) (< 1.33 tph)
19) Stator Main bushing S flow low (< 1.4 tph) (< 1.33 tph)
20) Stator Main bushing T flow low (< 1.4 tph) (< 1.33 tph)
21) Turbine over speed trip (electrical) (> 3300 rpm) (> 3330 rpm)
22) Turbine over speed trip H/W
23) Oil tank level very low ( 1000 mm
from top)
( 1150 mm
from top)
24) Turbine trip from desk operated 90 degC 130 degC
25) Turbine trip from bearing temp hi --- ---
26) Turbine trip from ATRS --- ---
27) Emergency trip from HMI --- ---
28) Fire protection 1 or 2 operated --- ---
29) Generator class B protection --- ---
30) Low Vacuum Trip Device operated --- ---
31) Manual Trip Device operated --- ---
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 25
2. TURBINE LUB OIL SYSTEM
2.1 AOP - 1
AUTO START1) SGC oil supply ON
2) SLC AOP -1 ON AND [ AOP -2 trippd OR Oil Pr < 4.8 ksc ]
AUTO STOP
1) SGC Oil Supply start-up step - 9 command
2) SGC Oil Supply shutdown step - 55 command
PROTECTION STOP
1) Oil tank level very low
2) Fire protection - 2 operated
2.2 AOP - 2
AUTO START
1) SLC AOP -2 ON AND [ AOP -1 tripped OR Oil Pr < 4.5 ksc ]
AUTO STOP1) SGC Oil Supply start-up step - 9 command
2) SGC Oil Supply shutdown step - 55 command
PROTECTION STOP
1) Oil tank level very low
2) Fire protection - 2 operated
2.3 EOP
PROTECTION ON
1) SLC EOP ON AND Lub oil pressure < 1.1 ksc
2) Lub oil pressure < 1.1 ksc AND
[ HP casing top mid temp > 120 degc OR
HP casing bottom mid temp > 120 degc ]
3) Lub oil press < 1.1 ksc ( Direct to DC Starter)
( Direct from Pr. Switch with SLC EOP-ON (MCM.Relay))
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 26
2.4 JOP -1
START PERMISSIVE
1) JOP -3 OFF
AUTO START
1) SLC JOP-1 ON AND Turbine Speed < 510 rpm
AUTO STOP
1) SLC JOP -1 ON AND Turbine Speed > 540 rpm
2) Turbine Speed < 510 rpm AND
Jacking oil pressure < 150 ksc AND
SLC JOP -3 ON TD15s
3) Turbine Speed < 2800 rpm ANDJOP -1 Voltage failed AND SLC JOP - 3 ON
4) JOP -1 Tripped AND SLC JOP -3 ON
5) SGC Oil Supply shutdown Step 54 command
PROTECTION STOP
1) Oil tank level very low
2) Fire protection - 2 operated
2.5 JOP - 3
START PERMISSIVE
1) JOP -1 OFF
AUTO START
1) JOP -1 Tripped AND SLC JOP -3 ON
2) Turbine Speed < 510 rpm AND Jacking oil pressure < 150 ksc
ANDSLC JOP -3 ON TD10s
3) Turbine Speed < 2800 rpm AND
JOP -1 Voltage failed AND SLC JOP - 3 ON
PROTECTION STOP
1) Oil tank level very low( > 1150 mm from top)
2) Fire protection - 2 operated
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 27
2.6 TURNING GEAR
OPEN PERMISSIVE
1) Turbine speed > 15 rpm OR
2) Seal oil pr. H2 side > 7.0 ksc AND
Seal oil Air to H2 side DP TE > 1.2 ksc AND
Seal oil Air to H2 side DP EE > 1.2 ksc
AUTO OPEN
1) SLC Turning gear ON AND Turbine Speed < 210 rpm
AUTO CLOSE
1) SLC Turning gear ON AND Turbine Speed > 240 rpm
2) SGC Oil Supply shutdown step -51 command
PROTECTION CLOSE
1) Lub oil pressure < 1.2 ksc
2.7 OIL TEMP CONTROL V/V
AUTO OFF
1) SGC oil supply shutdown step -55 command
2.8 OIL VAPOUR EXTRACTOR -1
AUTO START
1) Other vapour extractor tripped
2) SGC oil supply start-up step -2 command
AUTO STOP
1) Standby Oil vapour extractor ON
2.9 OIL VAPOUR EXTRACTOR-2
AUTO START
1) OVE- 1 OFF and Disc
2.10 LEAKAGE OIL PUMP
AUTO START
1) Leakage oil tank level > 50%
AUTO STOP
1) Leakage oil tank level < min
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 28
3 TURBINE HPCF SYSTEM
3.1 HP CONTROL FLUID HEATER
RELEASE ON1) Any HPCF circulation pumps ON AND
HPCF temp control vlv closed
AUTO ON
1) Control flow heater temp < 50 degc
2) SLC HPCF heating ON AND
HPCF tank fluid temp < 55 degc AND
HPCF temp control vlv closed
AUTO OFF
1) SGC HPCF shutdown step - 51 command
2) Control flow heater temp > 65 degc
3) SLC HPCF heating ON AND
[ HPCF tank fluid temp > 57 degc OR HPCF temp control vlv not
closed ]
PROTECTION OFF1) Control flow heater temp > 75 degc
2) Fire Protection-1 operated
3) Fire Protection-2 operated
4) Both HPCF circulation pumps OFF
3.2 HP CONTROL FLUID PUMP - 1
AUTO START
1) SLC HPCF Pumps ON AND HPCF pump 2 discharge pr. < 26
ksc
2) SLC HPCF Pumps ON AND HPCF pump 2 tripped
AUTO STOP
1) SGC HPCF shutdown step - 51 command
PROTECTION OFF
1) Fire Protection-1 OR Fire Protection-2 operated
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 29
3.3 HP CONTROL FLUID PUMP- 2
AUTO START
1) SLC HPCF Pumps ON AND HPCF pump 1 discharge pr. 30 ksc
2) HPCF Vapour Extractor - 2 tripped
3.5 HPCF VAP EXTR-2
AUTO START
1) HPCF Vapour Extractor - 1 tripped
3.6 HPCF CIRCULATION PUMP-1
START PERMISSIVE
1) HPCF Circulation pump-2 OFF
AUTO START
1) SGC HPCF on ANDHPCF press. > 30 ksc AND
Any HPCF Vap Extractor ON
AUTO STOP
1) SGC HPCF shutdown step - 51 command
PROTECTION OFF
1) HPCF tank level < min
2) Fire Protection -1 OR Fire Protection -2 operated
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 30
3.7 HPCF CIRCULATION PUMP-2
START PERMISSIVE
1) HPCF Circulation pump-1 OFF
AUTO START
1) HPCF press > 30 ksc AND
HPCF pump-1 off TD5s
AUTO STOP
1) SGC HPCF shutdown step - 51 command
PROTECTION OFF
1) HPCF tank level < min2) Fire Protection -1 OR Fire Protection -2 operated
3.8 HPCF TEMP CONTROL VALVE
AUTO OFF
1) SGC HPCF shutdown step - 51 command
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 31
3.9 HPCF ALARMS
1) Leakage Level High
Leak speed chang device >Min OR
Leak press TRANS INJW >Min OR
Over speed governor >Min
2) Hydraulic control fluid pressure low.
HPCF Pressure after pump -1 < 26 ksc AND
HPCF Pressure after pump -2 < 26 ksc AND
Turbine speed > 15 rpm
3) HPCF Filter DP high
Filter Supply Units DP > 0.6ksc OR
CF filter DP > 0.6ksc OR
LP Bypass filter DP > 0.6 ksc
4) Water CF Tank High
CF Conductivity High
5) HPCF Temperature Low/Fault < 50 degc
6) HPCF Temperature High/Fault > 60 degc
7) HPCF Pumps Fault
SLC HPCFs on with 10 sec delay AND
Any HPCF auto on command
8) HPCF Tank temp. low < 20 degc9) CONTIN Flow heater >75 degC
9) HPCF Tank level high > 59 % < 650 mm from top
10) HPCF Tank level low < 53 % > 800 mm from top
11) HPCF Tank level very low < 50 % > 750 mm from top
12) VAP EXTR System trouble
Both HPCF VAP EXTR- NOT ON AND
HPCF pr > 30 Ksc
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 32
4 EVACUATION SYSTEM
4.1 VACCUM PUMP 1 & 2
RELEASE START1) SEP water level > MIN
RELEASE STOP
1) System inlet valve closed
AUTO START
1) SGC Start-up Step-3 command
2) SLC vacuum pumps on AND Condenser pressure > 0.15 ksc
AUTO STOP
1) Through SGC Evacuationstep-51 command
2) SGC Evacuation start-up Step- 7 command AND Vacuum pump
selected
4.2 VACCUM PUMP SOL INLET VALVE 1 & 2
RELEASE OPEN1) Differential pressure across Inlet valve 0.15 ksc
AUTO CLOSE
1) SGC Evacuation shutdown step-51 command
2) SGC Evacuation start-up Step- 7 command AND Vacm pump
selected
4.3 SEAL WATER RECIRCULATION PUMP 1 & 2
ON RELEASE1) Separator water level > 360 mm
1) Vac p/p -2 ON
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 33
AUTO START
1) SGC start-up Step 3 command
2) SLC vacuum pumps on AND Condenser pressure > 0.15 ksc
CLOSE RELEASE
1) Vacuum pump OFF
AUTO CLOSE
1) SGC Evacuation shutdown step-51 command
2) SGC Evacuation start-up Step- 7 command
3) Vacuum pump OFF
4.4 MAKE UP SOLENOID VALVE 1 & 2
AUTO OPEN
1) Level in separator tank < 330 mm
AUTO CLOSE
1) Level in separator Tank > 360 mm TD5s
4.5 SEAL STEAM CONDENSER EXHAUST VALVE 1/2
AUTO OPEN
1) SGC evacuation start-up step 1 command
2) Seal steam condenser other exhaust tripped (OFF or DISC)
AUTO CLOSE
1) SGC Evacuation Shutdown step 53 command
( Vacuum breaker open status is required).
PROTECTION CLOSE
1) Seal steam condenser level High.
4.6 SEAL STEAM CONDENSER SEAL VALVES
AUTO OPEN
1) SGC evacuation start-up step 1 command
RELEASE OPEN1) Integral bypass valve open TD-5sec.
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 34
PROTECTION CLOSE
1) Seal steam condenser level-2 High
4.7 INT BYPASS VALVE FOR SEAL STEAM CONDENSER
SEAL VALVES
AUTO OPEN
1) Seal steam condenser seal valve
AUTO CLOSE
1) Seal steam condenser seal valve open
4.8 SEAL STEAM CONDENSER SAFETY VALVE
AUTO OPEN
1) Seal steam condenser level-2 High.
RELEASE OPEN
1) Integral bypass valve open TD-5sec.
AUTO CLOSE
1) SGC evacuation start-up step 1 command
4.9 INT BYPASS VALVE FOR SEAL STEAMCONDENSER
SAFETY VALVES
AUTO OPEN
1) Seal steam condenser LEVEL -2 HIGH
PROTECTION CLOSE
1) Seal steam condenser SAFETY valve open
4.10 SEAL STEAM VAP EXHAUST ISOL VALVE - 1/2
AUTO OPEN
1) Seal steam condenser exhaust ON
AUTO CLOSE
1) Seal steam condenser exhaust OFF
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 35
4.11 EVACUATION ALARMS
1) Seal steam condenser level high
Seal stm Cond lvl -1 high
Seal stm Cond lvl -2 high
2) Seal steam Condenser Valve Position Fault
Seal stm cond SOV limit switch not open or not closed AND
Seal stm Cond level -1 high AND
Seal stm Cond level -2 high
3) Seal Stm Cond Fault
Seal stm cond lvl -2 high TD1m AND
Seal stm cond SOV not open OR not closed
4) Switch OFF Stand by Vaccum Pump
Both Vacuum Pumps ON AND
Generator Load > 5 % AND
Condenser Press < 0.15 ksc
5) Switch ON Stand by Vaccum Pump
Generator Load > 5 % AND
Condenser Press > 0.15 ksc
6) Separator Water level < min
Sep-1 water lvl < min
Sep-2 water lvl < min7) SW Flow Low
CW recirculation pump 1 ON AND
SW Flow vac pump -1 < 14 m3/hr OR
CW recirculation Pump 2 ON AND
SW Flow vac pump -2 < 14 m3/hr
8) SLC Vaccum pump not ON
SLC Vaccum pumps OFF AND
Turbine Speed > 15 rpm
9) VP Seal stm temp hi
VP-1 Seal stm temp 40 degC
VP-2 Seal stm temp 40 degC
10) Seal Stm Cond Exh tripped
Seal stm cond Exh.1 tripped
Seal stm cond Exh.2 tripped
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 36
5. TURBINE FIRE PROTECTIONS
FIRE PROTECTION-1 OPERATED WILL COME WHEN
[Fire Protection-1 PB pressed in UCR.Fire Protection-1 PB pressed in MBLD-1
Fire Protection-1 PB pressed in MBLD-2] ] OR Fire protection -2
initiated
This will cause
Opens the vacuum Breaker on Protection
SGC HP CTRL FLUID OFF
SLC CTRL FLUID HTG OFF
SLC CTRL FLUID PUMPS OFF
Stops HPCF P/Ps
Stops HPCF Heater
Stops HPCF Recirculation P/Ps
Trips the Turbine
* The vacuum Breaker will open on Protection if
[Fire protection -1 initiated OR MOT level very low]
AND Generator Breaker OFF
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 37
FIRE PROTECTION-2 OPERATED WILL COME WHEN
1) MOT level very low OR
[Fire Protection-2 PB pressed in UCR. OR
Fire Protection-2 PB pressed in MBLD-1 ORFire Protection-2 PB pressed in MBLD-2]
This will Cause
Switch Off the SGC Oil Supply Program
Stops AOP-1 on protection
Auto OFF SLC AOP-1
Stops AOP-2 on protection
Auto OFF SLC AOP-2
Auto ON SLC EOP
Auto OFF SLC JOP-1
Stops JOP-1 on protection
Stops JOP-2 on protection
Starts JOP-3 on protection
Auto OFF SLC JOP-3
Auto OFF SLC Turning Gear
Trips the Turbine
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 38
6. EHTC
SPEED REFRENCE TRACKS ACTUAL SPEED WHEN
1) ( Load ctlr. o/p > speed ctlr. o/p + 5 % ) AND
Speed actual < 3030 rpm AND
Speed actual > 2940 rpm AND load ctlr. ON
2) Turbine tripped
SPEED REF DELAYED IS RESTRICTED IF
1) Generator breaker not ON AND
( NrTD - Nactual ) > 50 rpm
2) Generator breaker not ON AND
[ Power set point block OR TSC on & faulty] AND
Speed ref > speed ref delayed AND
Speed actual > 2850 rpm
DN/DT ACTS WHEN
1) Speed slope value low ( < 108 rpm / min ) AND
Speed ctlr. output > 0 % ANDSpeed actual Nact > 725 rpm AND
Speed actual Nact > 2850 rpm AND
Generator breaker not on AND
HP ESV # 1 not close AND
HP ESV # 2 not closed AND
Speed set point not balanced AND
Nr > 650 rpm
LOAD REFERENCE TRACKS ACTUAL LOAD WHEN
1) Pressure ctlr. in action AND IP mode selected AND Load actual
< 30 %
LOAD CTRLR BECOMES ON / OFF ONLY WHEN
1) ( Speed ctlr. output > load ctlr. output ) AND Speed ctlr. in
action
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 39
ISOLATED GRID IS DETECTED WHEN
1) Speed > 84.33 % AND Load ctlr. not off AND
Load error > 8.4 % for 6 sec. AND
Speed ctlr. not in action AND Pressure ctlr. not in action
ISOLATED GRID RESETS WHEN
1) Generator breaker off
2) load error < 8.4 % AND Reset command given
LOAD CTLR.O/P TRACKS PR. CTLR.O/P+2% WHEN
1) Press ctlr. in action AND
Actual load > final load set pt AND Load < load ref.
LOAD CTLR. O/P TRACKS SPEED CTLR. O/P WHEN
1) ( Pact. < station load AND Load ctlr. error > 5 %)
2) Generator Breaker off
3) Load ctlr. off AND Pressure ctlr not on
LIMIT PRESSURE MODE CAN BE SELECTED IF
1) Boiler ctlr. not tripped to manual ( is in auto ) AND
Turbine follow Boiler from CMC not selected AND
IP mode not selected from OWS
INITIAL PRESSURE MODE GETS SELECTED IF
1) Boiler ctlr. is in manual
2) Turbine follow Boiler from CMC not selected
3) IP mode selected from OWS
SPEED CTLR. IN ACTION IF
1) Generator Breaker off
2) Turbine Tripped Ch - 1/Ch -2
3) Speed ctlr. o/p+100% < max(speed ctlr. o/p, load ctlr. o/p)
4) Speed ctlr. o/p > Load ctlr. o/p
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 40
LOAD CTLR. IN ACTION IF
1) Load ctlr. not off AND
Isol. Grid not detected AND
[ Speed OR Press. ctlr. not in action ]
PRESS. CTLR. IN ACTION IF
1) Press. ctlr. o/p < min [ (Speed ctlr. o/p + 100 %) ,
max(speed ctlr. o/p , load ctlr. o/p) ]
TRACKING DEVICE CAN BE MADE ON IF
1) EHTC fault is not persisting ANDStarting device position healthy AND
EHC posn. 1 and 2 healthy AND
Speeder gear posn. Healthy AND
Plunger coil healthy AND
Tracking device no off cond. AND
Turbine tripped not present AND
No EHTC fault AND
Speed signal no fault
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 41
7 GENERATOR AUXILIARIES
7.0 PRIMARY WATER PUMP 1 & 2
AUTO START1) SLC PW pumps on AND PW Tank level > 155mm
AND Other PW pump off
2) SLC PW pumps on AND
PW Tank level > 155mm AND
Other PW pump on AND Pressure after other PW pump < 5 ksc
STOP PERMISSIVE
1) Stand by PW Pump on AND PW press. after std by pump > 5
ksc TD5s
2) SLC PW pumps off.
7.1 NaOH DOSING PUMP
START RELEASE
1) Treated water flow > min
AUTO START
1) Conductivity after ion exchanger < 1us/cm
AUTO STOP
1) Conductivity after ion exchanger > 3 us/cm TD10s OR
2) Conductivity after main filter > 2.5 us/cm TD10s OR
2) NaOH tank level < min
PROTECTION STOP
1) Treated water flow < min
7.2 PW TEMP CONTROL VALVE
PROTECTION OPEN
1) PW inlet temp > 66 degc
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 42
7.3 SEAL OIL PUMP - 1 AIR SIDE
AUTO START
1) SLC SO Pump (AS) on AND
SO storage tank level not low AND SO pump 2 (AS) off
2) SLC SO Pump (AS) on AND
SO storage tank level not low AND
SO pump 2 (AS) on AND SO pr after SOP-2 (AS) < 05 ksc TD2s
3) SO p/p-2 OFF and SO p/p-2 discrepancy
4) SGC Gen seal oil Start-up step-1 command
STOP PERMISSIVE
1) SO pump 2 (AS) on AND SO pr after SOP-2 (AS) > 5 ksc TD5s
2) SLC SO pump (AS) off
7.4 SEAL OIL PUMP - 2 AIR SIDE
AUTO START
1) SLC SO Pump (AS) on AND
SO storage tank level not low AND
SO pump 1 (AS) on AND SO pr after SOP-1 (AS) < 5 ksc TD2s
2) SLC SO Pump (AS) on AND SOP-1 (AS) OFF and
discrepancy .
STOP PERMISSIVE
1) SO pump 1 (AS) on AND SO pr after SOP-1 (AS) > 5 ksc TD5s
2) SLC SO pump (AS) off
7.5 SEAL OIL PUMP - 3 AIR SIDE (DC)
AUTO START
1) DC SOP local PB On command with local selected
2) SLC DC SOP - 3 On AND SO/H2 DP (TE/EE) < 0.9 ksc TD2s
3) SLC DC SOP - 3 On AND
[ SO pump 1 (AS) OFF OR SO pr after SOP -1 (AS)
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 43
STOP PERMISSIVE
1) SO pump 1 (AS) on AND SO pr after SOP -1 (AS) > 5 ksc
TD5s
2) SO pump 2 (AS) on AND SO pr after SOP -2 (AS) > 5 ksc
TD5s
3) SLC DC SO pump 3 off.
MANUAL STOP
1) DC SOP local PB off command with local selected
2) Remote selected & Remote off command
7.6 SEAL OIL PUMP - 4 H2 SIDE
START PERMISSIVE1) Any Seal oil pump (AS) on AND Seal oil tank level > min
AUTO START
1) SGC Gen seal oil start-up Step 3 Command
PROTECTION STOP
1) Seal oil tank level low
2) SOP Pressure air side < 4.5 ksc TD3s
7.7 BEARING EXHAUST FAN 1 & 2
AUTO START
1) SLC Brg exhaust fan on AND
Other Brg exhaust Fan on AND
Press at respective Brg exhaust fan > -5 mbar TD2s
2) SLC Brg exhaust fan on AND Other Beg exhaust Fan off
3) SGC Gen seal oil start-up step-1 command
STOP PERMISSIVE
1) Other Brg exhaust fan on AND
Press at respective Brg exhaust < -5 mbar TD5s
2) SLC Brg exhaust fan Off
7.8 EXCITER AIR DRIER
AUTO ON1) SLC Air Drier on AND Turbine speed < 210 rpm
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 44
OFF PERMISSIVE
1) Exciter Shut down Heater off
AUTO OFF
1) Turbine speed > 240 rpm AND
Exciter Shut down Heater Off AND SLC Air Drier On
7.9 EXCITER SHUT DOWN HEATER
ON PERMISSIVE
1) Air drier on
AUTO ON
1) SLC air drier on AND Air Drier On ANDTurbine speed 240 rpm OR Cold air temp >50 degc]
PROTECTION OFF
1) Cold air temp > 90 degc
2) Air drier off
7.10 CO2 FLASH EVAPORATOR
AUTO ON
1) SLC CO2 Flash Evaporator On AND
CO2 Flash Evaporator temp. < 145 degc
AUTO OFF:1) SLC CO2 flash evaporator off
PROTECTION OFF:
1) CO2 Flash Evaporator temp. > 150 degc
7.11 COLD GAS TEMP CONTROL VALVE
PROTECTION ON
1) Cold gas temp > 55 degc
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 45
7.12 GAS DRIER HEATER
START PERMISSIVE:
1) Gas drier blower ON for 10 min
AUTO ON
1) SLC gas drier ON AND Air temp at drier outlet < 60 degc
TD10s
AUTO OFF
1) Air temp. at Gas exhaust > 100 degc
PROTECTION OFF
1) Gas drier blower off2) Gas drier heater temp > 150 degc
3) Gas drier blower ON for 4 hrs
7.13 GAS DRIER BLOWER
START PERMISSIVE
1) Gas drier blower LS-1 OR 2 open
AUTO ON
1) SLC gas drier ON
OFF PERMISSIVE
1) Gas drier heater off
AUTO OFF
1) SLC gas drier ON AND Air temp. at drier O/L < 60 C AND Htr
not On
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 46
7.14 GAMP ALARMS
1) Oil level in Pre chamber (TE/EE) High
2) Liquid at main leads bottom High
3) Liquid at main leads top High
4) Level in SOST low
5) Pressure after AC SOP -1/2 (AS) low ( < 5 ksc)
6) Pressure after DC SOP -3 (AS) low ( < 5 ksc)
7) Pressure after AC SOP -4 (H2S) low ( < 5 ksc)
8) DP across SO filter AS/H2S High ( > 0.9 ksc)
9) SO Pr. (TE/EE) Air side Low ( < 4.5 ksc)
10) SO temp after cooler (AS) High (> 50 degc)
11) SO temp after cooler (H2S) High (> 50 degc)
12) SO temp after cooler V High (> 55 degc)
13) SO/H2 Diff Pr (TE AND EE ) High (>1.7 ksc)
14) SO/H2 Diff Pr (TE AND EE ) low (< 0.9 ksc)
15) H2 Pressure in Manifold low ( < 15 ksc)
16) H2 Pressure in Gen Casing low ( < 3.3 ksc)
17) H2 Pressure in Gen Casing High ( > 3.8 ksc)
18) H2 purity in Gen Casing low ( < 95 %)
19) PW Pr. after Pump low (< 5 ksc)
20) DP Pr. Winding High ( > 1.5 ksc)
21) PW temp after cooler V High ( > 55 degc)
22) Stator Wdg Flow low ( < 54 m3/hr)
23) Stator Wdg Flow V low ( < 48 m3/hr)
24) Flow through R bush V low ( < 1.33 m3/hr)
25) Flow through S bush V low ( < 1.33 m3/hr)
26) Flow through T bush V low ( < 1.33 m3/hr)
27) PW Pr. at stator Wdg I/L High ( > 3.8 ksc)
28) Hot Gas temp. Coolers A AND B High ( > 60 degc)
29) Hot Gas temp. Coolers C AND D High ( > 60 degc)
30) Cold Gas temp. Coolers A AND B High ( > 55 degc)
31) Cold Gas temp. Coolers C AND D High ( > 55 degc)
32) Cold Gas temp. Coolers V High ( > 60 degc)
33) Temperature Hot Air Main Exciter High ( > 75 degc)
34) Temperature Hot Air Main Exciter V High ( > 80 degc)
35) PW press. Stator I/L Low ( < 2.8 ksc)
36) SO Pr. AS (TE/EE) Low ( < 4.9 ksc)
37) PW temp at o/l High ( > 60 degc)
38) Conductivity after Winding High ( > 3 uS/cm) TD5m
39) Conductivity after main filter High ( > 3 uS/cm) TD5m
40) Conductivity after Ion exchanger low (< 1uS/cm) TD5m
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 47
8 TDBFP
8.1 PROTECTION
1) TDBFP working AND suction flow very low ( < 100 tph )
2) Deaerator level very low ( < -1610 mmwc)
3) TDBFP Lub oil header press. very low ( < 1.0 ksc)
4) TDBFP Suction valve not open
5) TDBFP Exhaust stm temp very high ( > 120 degc)
6) TDBFP Live steam pressure very high ( > 12.5 ksc)
7) TDBFP Exhaust steam pr. very high ( > -0.6 ksc)
8) Governing oil press. very low ( < 4.5 ksc)
9) Trip oil press. very low ( < 2 ksc)
10) Turbine Axial shift high ( > 0.7 mm)
11) Turbine eccentricity very high ( > 92 mic)
12) Trip PB operated
13) Trip command from OWS
14) Turbine over speed ( > 6300 rpm )
15) Turbine GB i/p vibration very high ( > 70 mic)
16) Turbine GB o/p vibration very high ( > 70 mic)
17) Turbine FJB vibration very high ( > 70 mic)
18) Turbine RJB vibration very high ( > 70 mic)19) Turbine GB brg temp very high ( > 120 degc)
20) Turbine bearing temp very high ( > 120 degc)
21) Booster pump brg temp very high ( > 95 degc)
22) Booster pump thrust brg temp very high ( > 105 degc)
23) BFP thrust brg temp metal very high ( > 105 degc)
24) BFP brg temp very high ( > 95 degc)
25) FW Suction / disch DT high ( > 15 degc )
26) TDBFP working AND suc flow < Variable set point trip
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PROTECTIONS AND INTERLOCKS DIARY
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8.2 TDBFP PERMISSIVES
TDBFP Suction valve open AND
Deaerator level adequate AND
TDBFP Casing top/ btm DT < 20 degc AND
Condenser press. < -0.5 ksc AND
Lub oil header press. > 1.5 ksc AND
BFP LOP p/p disch pr > 12.5 kg
Lub oil temp after clr < 45 degc AND
Governing oil press. > 6.5 ksc AND
TDBFP gearbox brg temp < 105 degc AND
TDBFP turbine brg temp < 105 degc AND
TDBFP journal brg temp < 90 degc AND
TDBFP thrust brg temp < 100 degc ANDTDBFP BP journal brg temp < 90 degc AND
TDBFP BP thrust brg temp < 100 degc AND
Any LOP ON AND
TDBFP not working AND
TDBFP Speed > 30 rpm AND
TDBFP Aux steam block vlv open AND
Aux steam press. > 12 ksc AND
Aux steam temp >280 degc ANDAux steam superheat > 50 degc AND
TDBFP suction / disch DT > 10 degc
8.3 TDBFP DISCHARGE VALVE
OPEN PERMISSIVE
1) TDBFP discharge IBV open
AUTO OPEN
1) SGC TDBFP turbine start-up step 34 cmd
2) TDBFP working AND Discharge press. > 40 ksc
3) TDBFP discharge IBV open and OPEN cmd from OWS
AUTO CLOSE
1) SGC TDBFP turbine start-up step 21 cmd
2) SGC TDBFP turbine shutdown step 55 cmd
3) TDBFP Tripped
4) TDBFP not working ANDDischarge header press > 60 ksc
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TDBFP WORKING
1) TDBFP ESV open AND
Speed > 800 rpm AND
Remote engagement oil press > 3.5 ksc AND
[ Main CV >=2 % open OR CRH/Aux CV >=2 % open ]
8.4 TDBFP RECIRCULATION VALVE
CLOSE PERMISSIVE
1) TDBFP suction flow >550 tph AND
FW suction / disch. DT < 10 degc AND
No auto open command
2) TDBFP not working AND No auto open command
AUTO OPEN
1) TDBFP Working. AND
[ Suction flow < 400 tph OR FW suc./disch. DT > 10 degc OR
Suction flow measurement fault ]
3) SGC TDBFP turbine start-up step 20 cmd
4) SGC TDBFP turbine shutdown step 55 cmd
PROTECTION OPEN
1) TDBFP suction flow < 250 tph
2) TDBFP not working
AUTO CLOSE
1) TDBFP suction flow > 850 tph AND
FW suc./disch. DT < 10 degc TD- 5 sec
2) SGC TDBFP turbine start-up step-39 cmd3) TDBFP var set point: CLOSE TD- 5 sec
TDBFP variable set point: CLOSE
1) Diff between Calc Flow and suction flow > 50 t/hr
2) TDBFP FW suc flow >=550 t/hr
3) TDBFP speed meas NO fault
4) TDBFP suc & disch temp not HI 10 deg C
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8.5 TDBFP REMOTE ENGAGEMENT SOLENOID V/V
OPEN / ENERGISE PERMISSIVE
1) TDBFP remote engagement oil pressure < 3.5 ksc AND
TDBFP journal brg temp < 90 degc AND
TDBFP thrust brg temp < 100 degc AND
TDBFP BP journal brg temp < 90 degc AND
TDBFP BP thrust brg temp < 100 degc AND
TDBFP turbine brg temp < 105 degc AND
TDBFP gearbox brg temp < 105 degc AND
Discharge vlv closed AND
Recirculation vlv open AND
Lub oil temp after cooler < 45 degc AND
Control oil header press. > 6.5 ksc AND
Lub oil press. > 1.5 ksc AND
Condenser press. < -0.5 ksc AND
TDBFP Casing top/ btm DT < 20 degc AND
TDBFP Suction / Disch. DT < 10 degc AND
Deaerator level adequate AND
TDBFP SUC valve open
AUTO OPEN / ENERGISE1) SGC TDBFP turbine start-up step 23 cmd
AUTO CLOSE / DEENERGISE
1) TDBFP remote engagement oil pressure > 3.5 ksc
2) SGC TDBFP turbine start-up step 24 cmd
8.6 TDBFP OIL VAPOUR EXTRACTOR FAN- A & B
AUTO START
2) Other OVE tripped
3) Other OVE off AND SGC TDBFP oil supply start-up step-1 cmd
AUTO STOP
1) SGC TDBFP oil supply shutdown step-58 cmd.
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PROTECTIONS AND INTERLOCKS DIARY
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8.7 TDBFP LUB OIL PUMP - A & B
AUTO START
1) Other LOP tripped
2) Other LOP start cmd given AND pump not ON TD2s
3) [ TDBFP working OR Other LOP ON ] AND
[ Lub oil disch. hdr. press. < 1.5 ksc OR LOP disch. press. < 7
ksc ]
4) Other LOP off AND SGC TDBFP oil supply start-up stp-2
cmd
RELEASE STOP
1) TDBFP not working
2) TDBFP speed zero and TDBFP speed 1.5 ksc AND
LOP disch. press. > 7 ksc
AUTO STOP
1) SGC TDBFP oil supply shutdown step-57 cmd
8.8 TDBFP EMERGENCY OIL PUMP
AUTO START
1) EOP Auto on selected AND
TDBFP lub oil hdr. press. very low
RELEASE STOP
1) [ EOP Auto on not selected OR TDBFP lub oil hdr. press. not
very low ] AND[ Any LOP on OR TDBFP speed zero ]
AUTO STOP
1) SGC TDBFP oil supply shutdown Step-57 cmd
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PROTECTIONS AND INTERLOCKS DIARY
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8.9 TDBFP JACK OIL PUMP
AUTO START
1) TDBFP Turbine speed < 510 rpm
2) SGC TDBFP oil supply start-up step-7 cmd
3) SGC TDBFP oil supply shutdown step-53 cmd
STOP PERMISSIVE
1) Speed zero and TDBFP speed 540 rpm
AUTO STOP
1) SGC TDBFP oil supply start-up step-9 cmd
2) SGC TDBFP oil supply shutdown step-56 cmd
3) TDBFP Turbine speed > 540 rpm
8.10 TDBFP TURNING GEAR VALVE
AUTO OPEN
1) [TDBFP turbine Speed < 510 rpm
SGC TDBFP oil supply start-up step-6 cmd
SGC TDBFP oil supply shutdown step-52 cmd] AND2) LO to turning gear valve closed OR Speed 540 rpm
2) TDBFP turbine Casing temp < 85 degc
AUTO CLOSE:
1) TDBFP turbine Speed > 540 rpm2) SGC TDBFP oil supply start-up step-9 cmd
3) SGC TDBFP oil supply shutdown step-55 cmd
4) LO to turning gear valve Open AND Speed >=200 rpm
8.11 TDBFP ENGAGE SOLENOID VALVE
RELEASE OPEN / ENERGISE
1) TDBFP Speed zero AND Speed < 10 rpm AND
TDBFP Engage / diseng oil pump on
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AUTO OPEN / ENERGISE
1) SGC TDBFP oil supply start-up step-5 cmd
RELEASE CLOSE / DEENERGISE
1) TDBFP Speed zero AND Speed < 10 rpm AND
TDBFP Engage / diseng oil pump on
AUTO CLOSE / DEENERGISE
1) SGC TDBFP oil supply start-up step-6 cmd
8.12 TDBFP DISENGAGE SOLENOID VALVE
RELEASE OPEN
1) TDBFP turb. Speed < 300 rpm AND
TDBFP engage / diseng oil pump ON
8.13 TDBPF ENGAGE / DISENGAGE OIL PUMP
START PERMISSIVE
1) TDBFP LOP discharge hdr. press. not low >1.5 kg
AUTO START:1) SGC TDBFP oil supply start-up step-5 cmd
AUTO STOP :
1) TDBFP pump engaged OR disengaged TD5s
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PROTECTIONS AND INTERLOCKS DIARY
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9. MDBFP
START PERMISSIVES
[ AOP ON AND Lub oil press. > 2 ksc 2/3 ] TD2s AND
MDBFP Suction valve open AND
D/A level not low (> +20 mm) 2/3 AND
Working oil temp. upstream clrs < 110 degc 2/3 AND
Working oil temp. down stream clrs < 75 degc AND
HC lub oil temp down stream clrs < 55 degc 2/3 AND
MDBFP casing top / bottom DT < 22 degc AND
MDBFP journal bearing temp < 90 degc AND
MDBFP thrust bearing temp < 100 degc AND
Hydraulic coupling bearing temp < 90 degc AND
MDBFP motor journal bearing temp < 85 degc AND
MDBFP motor winding temp < 125 degc AND
Booster pump journal bearing temp < 90 degc AND
Booster pump thrust bearing temp < 100 degc AND
MDBFP CW header press. > 3.5 ksc AND
MDBFP HC tank level not low AND
MDBFP Recirculation Valve open AND
MDBFP CW Valve close AND[ [MDBFP discharge v/v AND IBV Close] OR MDBFP Standby
Selected ] AND
[ [MDBFP Rapid Start Up Solenoid SOV92 AND SOV93 ON
AND
Scoop position min. (0%) ] OR Hyd. coupling min/cls (50 tph)
2) MDBFP suction flow low ( < 100 tph) TD30s
3) HC lub oil header press. very low (< 0.8 ksc) 2/3
4) HC working oil temp very high (>130 degc) 2/3
5) HC working oil press very low (
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7) MDBFP suction & discharge DT >15 degc 2/3
8) Lub oil temp. downstream clr very high (> 60 degc) 2/3
9) MDBFP journal bearing temp very high (> 95 degc)
10) MDBFP thrust bearing temp. very high ( >105 degc)
11) MDBFP motor winding temp very high ( >130 degc)
12) D/A level very low (< -1610 mm) 2/3
13) MDBFP motor journal bearing temp very high (> 90 degc)
14) Hyd. coupling bearing temp very high (> 95 degc)
15) Booster pump thrust bearing temp very high (> 105 degc)
16) Booster pump journal bearing temp very high (> 95degc)
17) EPB acted
MDBFP AUTO START
1) [ MD BFP in Standby AND
[ TD BFP-A tripped OR TD BFP-B tripped ] ]
2) Command from MDBFP Startup Sequence Step # 07
MDBFP AUTO STOP
1) Command from MDBFP Shutdown Sequence step # 51
9.1 MDBFP AOP
AOP AUTO START
1) MDBFP Auto Start
2) MDBFP ON AND Lub oil press. low ( 15ksc) AND BFP OFF
5) MDBFP OFF AND MDBFP Reverse Rotation Acted
6) Command from Startup Sequence Step # 06
7) MDBFP OFF AND 30 minutes hasn't elapsed to BFP OFF
status.
*Auto start command of A.O.P will persist for 30.min.
AOP AUTO STOP
1) MDBFP ON AND LO press. high (> 2.5 ksc) 2/3 TD2s
2) Command from Startup sequence step # 13- A
3) Command from Shutdown sequence step # 54- A
4) MDBFP OFF for 30 min AND Any bearing temp. not high
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PROTECTIONS AND INTERLOCKS DIARY
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9.2 MDBFP RECIRCULATION VALVE
AUTO OPEN
1) MDBFP flow measurement fault
2) MDBFP ON AND
Suction flow < 400 tph AND
Its Variable Set point Fault
3) MDBFP ON AND
Its Variable Set Point no fault AND
Diff of MDBFP Suction flow and Corrected Spd less than 5 tph
4) MDBFP ON AND Discharge / Suction DT >10 degc
5) Command from Startup sequence step # 02- A
6) Command from Shutdown sequence step # 52- B
PROTECTION OPEN
1) MDBFP Suction flow low ( 50 tph ] ORMDBFP Suction flow > 850 tph ] AND
MDBFP Disch / Suction DT 50 tph ] OR
MDBFP Suction flow more (>850 tph) ] AND
MDBFP Disch /Suction DT 40 ksc TD2s
2) Command from Startup Sequence Step # 16
3) Any TDBFP ON AND MDBFP Standby Selected AND
Disch. header press. > 60 ksc
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OPEN RELEASE
1) Discharge Valve I.B.V Opened AND Reverse Rotation Not
Acted
AUTO CLOSE
1) MDBFP OFF AND in Stdby AND MDBFP Reverse rotation
acted
2) MDBFP OFF AND in Stdby AND MDBFP Suction press. > 15
ksc
3) MDBFP OFF
4) Command from Sequence Startup Step # 06-A
5) Command from Sequence Shutdown Step # 53-A
6) MDBFP OFF AND in standby AND Discharge press. < 40 ksc
TD2m
CLOSE RELEASE
1) MDBFP OFF
9.4 MDBFP DISCHARGE IBV
AUTO OPEN1) MDBFP ON AND MDBFP Disch header. press. > 40 ksc TD1s
2) Command from Startup Sequence Step # 15- A
3) MDBFP Selected standby AND
Any TDBFP ON AND Discharge header press. > 60 ksc TD2s
AUTO CLOSE
1) Command from Startup Sequence Step # 06- B
2) Command from Startup Sequence Step # 17- B
3) MD BFP Discharge valve opened
4) Command from Shutdown Sequence Step # 53- B
9.5 MDBFP RAPID START-UP SOLENOID - 91/92
AUTO OPEN
1) MD BFP Auto Start
2) Command from Startup Sequence Step # 05- A
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AUTO CLOSE
1) MD BFP ON for 5.sec
2) MD BFP Reverse Rotation Acted
3) Command from Startup Sequence Step # 11- A
2) MD BFP STDBY SELECTED & MD BFP Reverse Rotation Acted
3) MD BFP STDBY SELECTED & SUC PR >15 KG
OPEN RELEASE
1) MD BFP standby selected AND Its Reverse Rotation Not Acted
9.6 MDBFP CW VALVE
AUTO OPEN
1) MD BFP ON
2) Command from Startup Sequence Step # 10- A
CLOSE RELEASE
1) MD BFP OFF
AUTO CLOSE
1) MD BFP Selected standby AND
Discharge header press. > 60 ksc TD2s ANDAny TDBFP ON
2) Command from Startup Sequence Step # 01-A
3) Command from Shutdown Sequence Step # 53- C
4) MD BFP OFF
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10 CEP
START PERMISSIVE
CEP Suction valve open AND
Hotwell level not low (>-250 mm) 2/3 AND
Swgr. available AND
Thrust bearing temp < 100 degc AND
Motor bearing temp. < 85 degc AND
Motor winding temp. < 125 degc AND
Recirculation valve 40% open AND
Vent valve open AND
[[CEP Standby selected AND Its disch v/v open ] OR
CEP discharge valve closed ]
TRIP PROTECTION
1) Hotwell Level very low ( < - 1850 mm ) 2/3
2) CEP ON AND Discharge press. low ( < 18 ksc )
3) CEP ON for 10 sec AND Flow through CEP low ( < 300 tph)
TD5s
4) Thrust bearing temp. very high ( > 105 degc)5) Motor bearing temp. very high ( > 90 degc)
6) Motor winding temp. very high ( > 130 degc)
7) Suction valve not open
AUTO START
1) Pump Selection Standby AND
Other Running pump Tripped
2) Pump Selection Standby ANDAny other pump ON for 30 sec AND
Discharge header press. low (
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10.1 CEP DISCHARGE VALVE
AUTO OPEN
1) CEP ON AND Discharge press. > 18 ksc TD2s
2) CEP Discharge press. > 18 ksc AND
Any other CEP ON AND CEP Standby Selected TD5s
3) Command from CEP Startup sequence step # 106
OPEN RELEASE
1) Discharge Valve I.B.V Open
CLOSE RELEASE
1) CEP OFF
AUTO CLOSE
1) CEP Stdby Selected AND Disch hdr. press. < 20 ksc TD2m
2) CEP OFF
3) Command from CEP Startup sequence step # 102
4) Command from CEP Shutdown sequence step # 202
DISCHARGE VALVE I.B.V AUTO OPEN
1) CEP ON AND Discharge press. > 18 ksc TD2s
2) CEP discharge press. > 18 ksc AND
Any other CEP ON AND CEP Standby Selected TD5s
DISCHARGE VALVE I.B.V AUTO CLOSE
1) Discharge valve opened
10.2 CEP VENT VALVE
AUTO OPEN
1) CEP discharge press. > 18 ksc AND
Any other CEP ON AND CEP Standby Selected TD5s
2) CEP OFF
3) Command from CEP Startup sequence step # 103
4) Command from CEP Shutdown sequence step # 202
AUTO CLOSE
1) CEP ON
OPEN RELEASE
1) CEP OFF
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11. ACW PUMP
START PERMISSIVES
1) Suction header press. > 1 ksc 2/3 AND
Suction valve open AND
[ Pump Selected Stdby AND Dischg vlv open ] OR Discg vlv clsd
TRIP PROTECTIONS
1) Pump ON for 08 sec AND Discharge press. high (>4.5 ksc )
2) Pump ON for 120sec AND Discharge valve not open
3) Pump ON and Suction Valve Not Open TD- 30 sec
4) Pump ON AND Any other ACW ON ANDCommon discharge hdr. press. > 4.5 ksc 2/3 TD30s
5) Suction header press. < 0.2 ksc 2/3 TD5s
AUTO START
1) Pump Selected Standby AND Any other ACW tripped
2) P/p Selected Stdby AND Any other p/p ON AND Dischg hdr. pr
< 2.3 ksc
3) Command from ACW Startup Sequence Step # 3-A
11.1 ACW PUMP DISCHARGE VALVE
AUTO OPEN
1) Pump Stdby Selected AND any other ACW ON AND Discharge
header press. > 2.3 ksc AND ACW-A OFF
2) Pump ON AND Discharge press. > 2.3 ksc
3) Command from ACW Startup Sequence Step # 4-A
AUTO CLOSE
1) Pump Selected stdby AND Disch hdr pr < 2.3 ksc AND ACW
OFF TD10s
2) ACW OFF
3) Command from ACW Startup Sequence Step # 1-A
4) Command from ACW Shutdown Sequence Step # 52-A
PERMISSIVE TO CLOSE
1) ACW-A OFF
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11.2 ACW PUMP SUCTION VALVE
AUTO OPEN
1) Pump Stdby Selected.
2) Command from ACW Startup Sequence Step # 02-A
AUTO CLOSE
1) Command from ACW Shutdown Sequence Step # 52-A.
2) ACW-A OFF
PERMISSIVE TO CLOSE
1) ACW-A OFF
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12. ECW PUMP
START PERMISSIVE
1) Motor winding temp. < 125 degc AND
Motor bearing temp. < 85 degc AND
ECW standby condition & Discharge valve open AND
Discharge valve Closed AND
Suction header press > 2.5 ksc 2/3 AND
Any ECW p/p ON OROverhead tank level not low ( > 950 mm)
ECW STANDBY CONDITION
1) Discharge v/v closed2) ECW standby selected AND Discharge v/v open
3) Motor winding temp. < 125 degc AND
4) Motor bearing temp. < 85 degc AND
5) Overhead tank level not low ( > 950 mm)
TRIP PROTECTIONS
1) ECW ON for 60sec AND Discharge valve not open
2) Suction valve not open
3) ECW ON AND Discharge hdr. press. very high (> 8.5 ksc)
4) Suction header press. very low (< 0.2 ksc) 2/3
5) Motor winding temp very high (> 130 degc)
6) Motor bearing temp very high (> 90 degc)
AUTO START
1) Pump Selection Standby AND Any other pump Tripped2) Pump Selection Standby AND Any other pump ON AND
Discharge hdr. pr. low
3) Command from Startup Sequence Step # 3
AUTO STOP
1) Command from Shutdown Sequence Step # 51
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12.1 ECW PUMP DISCHARGE VALVE
AUTO OPEN
1) Pump Standby Selected AND Its Start Permissive Available
AND
Any other pump ON AND Discharge header press. > 3 ksc
2) Pump ON AND Its Discharge press. > 5.4 ksc
3) Command from Start Up Sequence step # 04 - A
AUTO CLOSE
1) Pump Selected standby AND Discharge header press. < 3 ksc
2) Pump OFF
3) Command from Shutdown Sequence Step # 202
4) Command from Startup Sequence Step # 101
12.2 ECW O/H TANK MAKE UP VALVES (SG + TG)
EMG MU VALVE AUTO OPEN
1) ECW O/H Tank Level low (
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13 LP BYPASS
1) LP Bypass Reset Trip SOV Protection valve will act
at condenser wall temp > 90 C
2) Injection water v/v open command will be issued at
steam pressure before bypass v/v 1/2 > 6.8 ksc
Closure of LPBP , in vase of:
a) Condenser vacuum is low
b) Spray water pressure is low
c) Temperature of condenser body is high
Malfunctions of the turbine bypass, i.e. failure of the bypass valves to
open on demand, have to be counteracted by opening of the reheat
safety valves to ensure flow through the reheater. This prevents a heat
accumulation in the reheater tubes. For this purpose, the measure of
flow through reheater is the magnitude of the deviation between actual
and set pressure. The following conditions prevail.
1. If the control deviation rises above a set limit value (>30%) and
neither all bypass stop valves are fully open (25 %)
and all LP bypass stop valves are fully open, the command for opening
the reheater safety valves is also given on a time delay of 30 Seconds.
13.1 SEAL STEAM
1) Turbine Seal Steam Supply valve will get auto closed
on temperature interlock at
Seal Steam Header temp < 190 C
2) Gland steam press abnormal : > 450 mmwc OR
< 50 mmwc
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14. AUX PRDS
14.1 HT PRDS INLET ISOLATING VALVE ASV 21
OPEN PERMISSIVE
1) HT PRDS Isolating vlv ASV 21 IBV open
AUTO OPEN
1) HT PR control valve ASV 22 > 2 % open
2) HT PRDS Isolating vlv ASV 21 IBV open
AUTO CLOSE
1) HT PR control valve ASV 22 < 2 % open TD-1.5 sec
PROTECTION CLOSE
1) HT PRDS Temperature V High > 350 degc
2) LT PRDS Temperature V High > 285 degc
14.2 HT PRDS ISOL. VALVE ASV 21 IBV
AUTO OPEN
1) HT PRDS Isolating vlv ASV 21 IBV open
2) HT PR control valve ASV 22 > 2 % open
AUTO CLOSE
1) HT PRDS Isolating vlv ASV 21 open
2) HT PR control valve ASV 22 < 2 % open
PROTECTION CLOSE
1) HT PRDS Temperature V High > 350 degc
2) LT PRDS Temperature V High > 285 degc
14.3 HT PR CONTROL VLV ASV 22
PROTECTION CLOSE
1) MFT operated
2) HT PRDS Temperature V High > 350 degc
3) LT PRDS Temperature V High > 285 degc
4) CRH press > 18 ksc AND ASV 22
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14.4 LT PRDS INLET ISOLATING VLV ASV 25
AUTO OPEN
1) LT PR control valve ASV 26 > 2% open
AUTO CLOSE
1) LT PR control valve ASV 26 285 degc
14.5 LT PRDS CV BYP VLV ASV 28
CLOSE PERMISSIVE
1) LT PR CV bypass valve ASV 29 close
PROTECTION CLOSE
1) HT PRDS Temperature V High > 350 degc
2) LT PRDS Temperature V High > 285 degc
14.6 LT PR CONTROL VLV ASV 26
AUTO CLOSE
1) CRH press < 18 ksc
PROTECTION CLOSE
1) MFT operated
2) HT PRDS Temperature V High > 350 degc
3) LT PRDS Temperature V High > 240 degc
14.7 LT PRDS DESH. VALVE ASV 181
AUTO OPEN
1) HT PR control valve ASV 22 > 2% open
2) LT PR control valve ASV 26 > 2% open
AUTO CLOSE
1) HT PR control valve ASV 22 < 2% open AND
LT PR control valve ASV 26 < 2% open
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14.8 SPRAY BLOCK VALVE to PRDS FDV 43
AUTO OPEN
1) HT PR control valve ASV 22 > 2% open
2) LT PR control valve ASV 26 > 2% open
RELEASE CLOSE
1) HT PR control valve ASV 22 < 2% open AND
LT PR control valve ASV 26 < 2% open
AUTO CLOSE
1) HT PR control valve ASV 22 < 2% CLOSE
2) LT PR control valve ASV 26 < 2% CLOSE
3) LT PR control valve ASV 29 < 2% CLOSE
PROTECTION CLOSE
1) MFT operated
14.9 HT PRDS SPRAY ISOLATING VLV FDV 29
AUTO OPEN
1) [HT PR control valve ASV 22 > 2% open OR
HT APRDS spray control vlv FDV 30 >2 % open] AND
2) Main line selected
AUTO CLOSE
1) HT PR control valve ASV 22
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FORCED AUTO
1) HT PR control valve ASV 22 > 2 % open AND
2) Main line selected
14.11 HT PRDS SPRAY CONTROL VALVE FDV 31
AUTO CLOSE
1) HT PR control valve ASV 22 < 2% close
PROTECTION CLOSE
1) MFT operated
FORCED AUTO
1) HT PR control valve ASV 22 > 2 % open AND
2) Main line selected
14.12 LT PRDS SPRAY ISOLATING VLV FDV 33
AUTO OPEN
1) [LT PR control valve ASV 26 > 2% open OR
HT PR control valve ASV 22 > 2% open] and
2) Main line selected
RELEASE CLOSE
1) LT PR control valve ASV 26 < 2% open AND
HT PR control valve ASV 22
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AUTO OPEN
1) [LT PR control valve ASV 26 > 2% open OR
HT PR control valve ASV 22 > 2% open] and
2) Bypass line selected
RELEASE CLOSE
1) LT PR control valve ASV 26 < 2% open AND
HT PR control valve ASV 22 2% open] AND
2) Main line selected
14.15 LT PRDS SPRAY CONTROL VALVE FDV 46
AUTO CLOSE
1) HT PR control valve ASV 22 < 2% close ANDLT PR control valve ASV 26 < 2% close AND
ASV 29 < 2% open
PROTECTION CLOSE
1) MFT operated
FORCED AUTO
1) [HT PR control valve ASV 22 > 2 % open OR
LT PR control valve ASV 26 > 2% open] AND
2) Main line selected
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 71
15 LP HEATERS
15.1 LPH CONDENSATE INLET ISO. VALVE
OPEN RELEASE
1) LPH Cond. I/L Isolating valve I.B.V Open ANDLPH Level Not HI
AUTO OPEN
1) Command from Startup Sequence Step # 02- A
CLOSE RELEASE
1) LPH Bypass Valve Opened
AUTO CLOSE
1) Command from Shutdown Sequence Step # 52- A
PROTECTION CLOSE
1) LPH Bypass Valve Not ClosedAND
LPH Level very high 2/3
15.2 LPH CONDENSATE OUTLET ISO. VALVE
OPEN RELEASE
1) LPH Level Not HI
AUTO OPEN
1) Command from Startup Sequence Step # 02- A
CLOSE RELEASE
1) LPH Bypass Valve Open
AUTO CLOSE
1) Command from Shutdown Sequence Step # 52- B
PROTECTION CLOSE
1) LPH Bypass Valve Not Closed AND LPH Level very high 2/3
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 72
15.3 LPH CONDENSATE INLET ISO. IBV
OPEN RELEASE
1) LPH Level Not HI
AUTO OPEN
1) Command from Startup Sequence Step # 01-A
AUTO CLOSE
1) Command from Startup Sequence Step # 03-A
2) Command from Shutdown Sequence Step # 52-D
3) LPH Cond. I/L Isolating valve open
PROTECTION CLOSE
1) LPH Level very high 2/3
15.4 LPH BYPASS VALVE
AUTO OPEN
1) Command from Shutdown Sequence Step # 51-A
CLOSE RELEASE
1) LPH Cond. I/L AND O/L Isolating valve Open
AUTO CLOSE
1) LPH Cond. I/L AND O/L Isolating valve Open
2) Command from Startup Sequence Step # 03- B
PROTECTION OPEN
1) LPH Level very high 2/3
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 73
15.5 LPH 2 & 3 EXT STM VALVES
EXT STM ISOLATING VALVE OPEN RELEASE
1) LPH I/L Isolating valve open AND
O/L Isolating valve open AND
LPH level not high AND Turbine Not Tripped
EXT STM ISOLATING VALVE AUTO OPEN
1) Command from Start Sequence Step # 04- A
EXT STM ISOLATING VALVE AUTO CLOSE
1) Command from Shutdown Sequence Step # 52- A
EXT STM ISOLATING VALVE PROTECTION CLOSE
1) Turbine Tripped
2) LPH Level very high 2/3
3) LPH Cond. I/L Isolating valve Not Open
4) LPH Cond. O/L Isolating valve Not Open
5) LPH Cond. Bypass Valve Not Close
EXT STM DRN VALVE AUTO OPEN
1) Command from Startup Sequence Step # 01- B
2) Command from Shutdown Sequence Step # 51- A3) LPH EXT STM Isolating valve close
EXT STM DRN VALVE AUTO CLOSE
1) Command from Startup Sequence Step # 05- A
2) LPH EXT STM Isolating valve open
EXT STM DRN VALVE PROTECTION OPEN
1) LPH Level very high 2/3
2) Turbine Tripped
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 74
16. HP HEATERS
16.1 HPH 5A FW INLET ISOLATING VALVE
OPEN RELEASE
1) HPH-5A FW I/L isolating valve I.B.V opened AND
2) HPH-5A/6A level < 135 mm 2/3 (Not Hi)
AUTO OPEN
1) Command from Startup Sequence Step # 03-A
CLOSE RELEASE
1) [HPH FW 50% BYP Valve Opened AND
HPH-5B FW I/L Iso. Valve Opened ANDHPH-6B FW O/L isolating valve opened] OR
2) HPH FW 100% bypass valve opened
AUTO CLOSE
1) Command from Shutdown Sequence Step # 62-C
PROTECTION CLOSE
1) Release to Auto Close available AND
HPH-5A/6A Level > 415 mm 2/3 (HI HI)
16.2 HPH 5A FW INLET ISOLATING IBV
AUTO OPEN
1) Command from Startup Sequence Step # 1-A
2) HPH -5A iso valve open CMD
PERMISSIVE OPEN
1) HPH -5A/6A level not high
AUTO CLOSE
1) Command from Startup Sequence Step # 62-E
2) HPH-5A FW I/L isolating valve open
3) HPH-5A FW I/L isolating valve Close CMD
PROTECTION CLOSE
1) HPH-5A/6A Level > 415 mm 2/3 (Hi Hi)
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 75
16.3 HPH 6A FW OUTLET ISOLATING VALVE
OPEN RELEASE
1) HPH-6A FW O/L isolating valve I.B.V opened AND
HPH-5A/6A level < 135 mm 2/3
AUTO OPEN
1) Command from Startup Sequence Step # 03- B
CLOSE RELEASE
1) HPH FW 50% BYP Valve Opened AND
HPH-5B FW I/L Iso. Valve Opened AND
HPH-6B FW O/L Iso. Valve Opened OR
HPH FW 100% bypass Valve Opened
AUTO CLOSE
1) Command from Shutdown Sequence Step # 62 -D
PROTECTION CLOSE
1) Release to Auto Cls Available AND HPH-5A/6A Level > 415 mm
2/3
16.4 HPH 6A FW OUTLET ISOLATING IBV
AUTO OPEN
1) Command from Startup Sequence Step # 01-B
2) HPH -6A O/L iso valve open CMD
PERMISSIVE OPEN
1) HPH -5A/6A level not high
AUTO CLOSE1) Command from Startup Sequence step# 04-B
2) HPH-5A FW I/L isolating valve open
3) HPH-5A FW I/L isolating valve Close CMD Step # 62-F
PROTECTION CLOSE
1) HPH-5A/6A Level > 415 mm 2/3
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 76
16.5 HPH 5A(6A) EXT. STM VALVE AND NRV
OPEN PERMISSIVE
1) HPH-5A/6A LVL NOT HI
2) HPH-5A I/L isolating Valve Open AND
HPH-6A O/L isolating Valve Open
3) Turbine Not Tripped
4) [ HPH-5B FW I/L Iso. valve Closed AND
HPH-6B FW O/L Iso. valve Closed AND
HPH FW 50% BYP Valve Opened AND
HPH FW 100% bypass Valve Closed ] OR
[ HPH FW 100% bypass valve closed AND
HPH-5B FW I/L Iso. valve Opened AND
HPH-6B FW O/L Iso. valve Opened ANDHPH FW 50% bypass valve Closed ]
AUTO OPEN
1) Command from Startup Sequence Step # 10- A
AUTO CLOSE
1) Command from Shut down Sequence Step # 51- A
PROTECTION CLOSE
1) Turbine Not Tripped
2) HPH-5A FW I/L isolating valve Closed
3) HPH-6A FW O/L isolating valve Closed
4) HPH FW 100% BYP valve open
5) HPH-5A/6A level very high
HPH-5A EXT STM I/L NRV AUTO OPEN
1) Command from Startup Sequence Step # 11
HPH-5A EXT STM I/L NRV AUTO CLOSE
1) Command from Shutdown Sequence Step # 51
HPH-5A EXT STM I/L NRV PROTECTION CLOSE
1) Turbine Tripped
2) HPH-5A FW I/L isolating valve not opened
3) HPH-6A FW O/L isolating valve not opened
4) HPH FW 100% bypass valve not closed
5) HPH-5A/6A Level very high
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 77
HPH-5A/5B EXT STM DRN VALVE AUTO OPEN
1) Command from HPH-5A/6A Shutdown Seq Step # 202
2) Command from HPH-5B/6B Start-up Seq Step # 102
3) Command from HPH-5B/6B Shutdown Seq Step # 202
4) HPH-5A EXT STM Valve Closed AND
HPH-5B EXT STM Valve Closed
HPH-5A/5B EXT STM DRN VALVE AUTO CLOSE
1) Command from HPH-5A/6A Startup Seq Step # 112
2) Command from HPH-5B/6B Startup Seq Step # 112
3) HPH-5A EXT STM Valve opened
4) HPH-5B EXT STM Valve opened
HPH-5A/5B EXT STM DRN V/V PROTECTION OPEN
1) HPH-5A/6A Level very high
2) HPH-5B/6B Level very high
HPH-6A EXT STM DRN VALVE AUTO OPEN
1) Command from HPH-5A/6A Shutdown Seq Step # 201
2) Command from HPH-5A/6A Startup Seq Step # 101
3) HPH-6A EXT STM Valve
HPH-6A EXT STM DRN VALVE AUTO CLOSE
1) Command from HPH-5A/6A Startup Seq Step # 112
2) HPH-6A EXT STM Valve opened
HPH-6A EXT STM DRN V/V PROTECTION OPEN
1) HPH-5A/6A Level very high
16.6 HPH FW 50% BYPASS VALVE
OPEN RELEASE
1) HPH FW 50% BYP Valve I.B.V Open
AUTO OPEN
1) Command from HPH Startup Seq Step # 107
2) Command from HPH Shutdown Seq Step # 204
AUTO CLOSE
1) Command from HPH Startup Seq Step # 5- A
2) Command from HPH Shutdown Seq Step # 06- A
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 78
PROTECTION OPEN
1) HPH-5A/6A Level > 415 mm 2/3
2) HPH-5B/6B Level > 415 mm 2/3
CLOSE PERMISSIVE
1) [ HPH-5A I/L Iso. Valve Opened AND
HPH-6A O/L Iso. Valve Opened AND
HPH-5B I/L Iso. Valve Opened AND
HPH-6B O/L Iso. Valve Opened ] OR [ HPH FW 100% bypass
Valve Opened ]
BYP.VALVE I.B.V AUTO OPEN
1) Command from HPH Startup Seq Step # 06- A
2) Command from HPH Shutdown Seq Step # 54- A
BYP.VALVE I.B.V AUTO CLOSE
1) Command from HPH Startup Sequence Step # 08-B
2) Command from HPH Shutdown Sequence Step # 05- B
3) HPH FW 50% bypass Valve opened
4) Command from HPH Shutdown Sequence Step # 60-B
BYP.VALVE I.B.V PROTECTION OPEN
1) HPH-5A/6A Level > 415 mm
2) HPH-5B/6B Level > 415 mm
16.7 HPH FW 100% BYPASS VALVE
CLOSE PERMISSIVE
1) [ HPH-5A I/L Iso. Valve Opened AND
HPH-6A O/L Iso. Valve Opened AND
HPH-5B I/L Iso. Valve Opened AND
HPH-6B outlet Iso. Valve Opened ] OR
[ HPH-5A FW I/L Iso.Valve Opened AND
HPH-6A FW O/L Iso.Valve Opened OR
HPH-5B FW I/L Iso. Valve Opened AND
HPH-6B FW O/L Iso. Valve Opened AND
HPH FW 50% bypass Valve Opened ]
OPEN RELEASE
1) HPH FW 100% BYP Valve I.B.V Open
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 79
AUTO OPEN
1) Command from HPH Shut down Seq Step # 58- A
AUTO CLOSE
1) Command from HPH Startup Seq Step # 09- A
PROTECTION OPEN
1) [ HPH-5A FW I/L Iso. Valve Not Open OR
HPH-6A FW O/L Iso. Valve Not Open OR
HPH-5A/6A Level > 415 mm ] AND
[ HPH-5B FW I/L Iso. Valve Not Open OR
HPH-6B FW O/L Iso. Valve Not Open OR
HPH-5B/6B Level > 415 mm ]
BYP.VALVE I.B.V AUTO OPEN
1) Command from HPH Shut down Seq Step # 57- A
BYP.VALVE I.B.V AUTO CLOSE
1) Command from HPH Startup Sequence Step # 09-A
2) Command from HPH Shutdown Sequence Step # 59- A
3) HPH FW 100% bypass Valve opened
BYP.VALVE I.B.V PROTECTION OPEN
1) [ HPH-5A FW I/L Iso. Valve Not Open OR
HPH-6A FW O/L Iso. Valve Not Open OR
HPH-5A/6A Level > 415 mm ] AND
[ HPH-5B FW I/L Iso. Valve Not Open OR
HPH-6B FW O/L Iso. Valve Not Open OR
HPH-5B/6B Level > 415 mm ]
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 80
17. DEAERATOR
1 AS TO D/A PEGGING CV BP VALVEASV 10
PROTECTION CLOSE:
1) Deaerator level very high
2 D/A OVERFLOW CONTROL VALVE DRV 48
AUTO OPEN
1) Deaerator level high
PROTECTION OPEN
1) Deaerator level very high
AUTO CLOSE
1) Deaerator level low
3 CRH TO D/A PEGGING CV BP VALVE CRHV 8
PROTECTION CLOSE:
1) Deaerator level very high
4 D/A EXTRACTION VALVE EXV 13
OPEN PERMISSIVE
1) D/A level not High.
AUTO OPEN
1) Extraction steam pressure >3.5 ksc
PROTECTION CLOSE1) D/A level V High
2) Turbine tripped
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 81
5 D/A EXTRACTION LINE DRAIN VALVE EXV 15
AUTO OPEN
1) Turbine tripped
AUTO CLOSE
1) Extraction steam flow to D/A >10%
6 Main Cond CS CV ( CD-22) I/L iso valve
Auto open: CD-22 is opened by >2%
AutoClose: CD-22 is closed by 2%
AutoClose: CD-25 is closed by
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PROTECTIONS AND INTERLOCKS DIARY
KAHALGAON STAGE II 3 X 500 MW 82
18. CW PUMP
1 CW PUMP START PERMISSIVES
Sump level not low (>34.7 m) AND
Motor thrust bearing temp < 100 degc AND
Motor upper guide bearing temp NDE < 100 degc AND
Motor lower g
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