Interlocks Protections of Boiler 4x600MW
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Transcript of Interlocks Protections of Boiler 4x600MW
PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
1. MASTER FUEL TRIP PROTECTIONS:
SL NO
PARAMTR TRIP CONDN
ALARM
TRIP TIME DELAY
REMARKS
1 Both ID Fans OFF -- -- -- 3 hardwired contacts for each ID fan (2/3)
2 Both FD Fans OFF -- -- -- 3 hardwired contacts for each FD fan (2/3)
3 Water wall Circulation Incorrect ON DELAY
5 sec4 UCP: EMG PB &
ReleasePressed together
-- -- --
5 Any OWS: EMG trip comd
Initiated & Confirmed
-- -- --
6 Furnace Pressure V LO -- 2/3 Pressure Switches7 Furnace Pressure V HI -- 2/3 Pressure Switches8 Drum Level V LO ON
DELAY 5 sec
2/3
9 Drum Level V HI ON DELAY 10 sec
2/3
10 Total Air Flow V LO -- < 30% -- Flow Transmitters11 Loss of Reheat
ProtectionActed -- -- -- Arming:
12 Unit 220V DC Not Avlbl 2 sec 220V DC for LOTV solenoids13 Unit 24V DC
(FSSS internal)Not Avlbl -- -- -- 24V for MFT Panel
Hardwired trip14 Less than FB & loss of
AC in any elevation in service
Loss of 110V AC
-- -- 2 sec 110V AC for nozzle valve solenoidsArming: All feeders off
15 Unit Flame Failure Trip
Activated -- -- -- Arming: Any feeder proven
16 Loss of All Fuel Trip Activated -- -- -- Arming: Any LO nozzle valve not closed
17 Both Air Heaters off OFF -- -- 5 sec for indiv SAH
Air Heater OFF = Main motor OFF & Air pressure Low
18 All BFP OFF 10 secNOTE: All Trip Conditions are individually sensed by each MFT panel.
Final 2/3 Logic for Master Fuel Trip is hardwired in Purge Panel.
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW ) LOSS OF ALL FUEL TRIP (Arming: Any Nozzle valve Not closed )
Note: All conditions to be satisfied for trip
SN PARAMETER TRIP CONDN ALARM VAL TRIP VAL REMARKS
1. Loss of all fuel trip arming* AND 2. All feeders Off AND3. (LOTV Not Open) OR All EL.
LONV closed OR All Elevation Backup Trip
* Loss of all fuel Trip Arming is done when any elevation any nozzle valve not closed signal becomes true.
UNIT FLAME FAILURE TRIP (Arming: Any Feeder proven)
SN PARAMETER TRIP CONDN ALARM VAL
TRIP VAL REMARKS
Flame failure trip arming* & All Elevation A-H Voted no flame **
-- --
*Flame failure trip arming is done when any of the feeders is proven.** No flame VOTING LOGIC For Elevation A1. Feeder A STOP for More Than 2 sec OR2. EL AB Start And Loss of 110V AC Power for more than 2 sec OR3. EL AB 2/4 Light oil Nozzle V/V Not Proven & EL. AB 3/4 FB scan No flame.
LESS THAN FIREBALL OR LOSS OF AC IN ANY ELEV IN SERVICE
SN PARAMETER TRIP CONDN ALARM VAL
TRIP VAL REMARKS
1. All Feeders Off AND2. Any of the Oil EL.(AB, CD, EF, GH) Start and Loss of 110V AC ( ON TD 2 sec)
-- --
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
FSSS : PURGE PERMISSIVES:
S. No
PARAMETER REQ. STATUS SET VALUE
REMARKS
All PA Fans OFF --LOTV Closed --All Elevation All LONV Closed --All Feeders OFF --All Hot Air Gates Closed --All Elevations Discr Scanners
No Flame --
All Elevations Fireball Scanners
No Flame --
All Auxiliary Air Dampers Modulating Taken from inlet pressure switches for each damper
Total Air Flow > 30%< 40%
> Tph< Tph
100% = Total Air Flow at MCR =Tph
No Boiler Trip True MFT condition not present (but MFT Not reset)
NOTE: Purge Timer = 9 minutes, Post-Trip Purge Timer = 5 minutes.
LIGHT OIL TRIP V/V :
OPENING PERMISSIVES: AUTO CLOSING CONDITIONS:
1.1 Depress the LO trip valve OPEN pushbutton AND No MFT AND Light oil supply pressure adequate AND All LONV closed OR
2.1 Depress the LO trip valve OPEN pushbutton
AND 2.2 LFO Return oil trip valve OPEN
1.1MFT AND LO Return Trip valve not open
OR2.1 Atomizing air pressure very low AND any
light oil nozzle valve not closed AND No LO start/stop in any elevation AND LO Return valve not open
OR
2.2 LO header pressure very low AND any light oil nozzle valve not closed AND LO Return valve not open
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
OR2.3 Loss of 24V DC supply.
LO ELEVATION:
LO ELEVATION START PERMIT: LO ELEVATION TRIP CONDITIONS:
1. Light oil selected2. No MFT3. LOTV proven fully open4. Pulverizer start permit
4.1 Nozzle tilt horizontal AND air flow <40% MCR
OR4.2 Any oil elevation is in service
OR 4.3 Any feeder On.
AND 4.4 No MFT.
1. Master Fuel Trip Operated
OR 2. LOTV Not Opened
LIGHT OIL RETURN TRIP VALVE:
OPENING PERMISSIVES: AUTO CLOSING CONDITIONS:1. LFO return trip valve open PB pressed
AND2. All elevation LONV closed.
AND3. No auto closing conditions.
1. All El. LFO Nozzle valves not closed
OR2. LFO return trip valve close PB pressed
OR3. LFO Trip Valve closing command AND LFO
Return valve not closed
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
LIGHT OIL NOZZLE VALVE:
OPENING PERMISSIVES: AUTO CLOSING CONDITIONS1. The corner is not in scavenge
AND2. Atomizing air nozzle valve is proven open
AND3. None of the corner trip condition is present
AND4. HEA ignitor spark rod is in advanced position
AND5. Non existence of corner LO nozzle valve is
open
AND6. Non Existence of the condition in which LO
Nozzle valve open AND Discriminating scanner shows no flame
1. Scavenge start.
OR2. LO Nozzle valve open AND discriminating
scanners show no flame.
OR3. Light Oil Trip*
OR4. Loss of 24V DC in El. AB
AIR NOZZLE VALVE:
OPENING PERMISSIVES: AUTO CLOSING CONDITIONS1.1 HEA Rod advanced AND oil gun engaged
AND LO corner start AND EL. AB light oil selected AND Atomizing air manual isolation valve open AND scavenge valve closed.
OR1.2 Disc. Scanner Flame
AND2. LO nozzle valve closed AND Start scavenge
AND El. AB Light oil selected AND Light oil trip not available
Light oil Trip*
*Conditions for Light Oil Trip
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
1. Elevation AB back up trip OR LGM switch in off OR Oil gun not engaged
OR2.1 LO manual isolation valve not open OR Atomizing air manual isolation valve not open OR discriminating
scanner shows no flame.
AND2.2 LO corner not start AND Non availability of El. AB light oil selected and start scavenge.
OR 3.1 Atomizing air manual isolation valve not open OR LO nozzle manual isolation valve not open.
SCAVENGE NOZZLE VALVE:
OPENING PERMISSIVES: AUTO CLOSING CONDITIONS1. Light oil trip not present
AND2. Atomizing air nozzle valve open
AND3. Open scavenge valve signal available
1. Atomizing air nozzle valve not open
AND2. Close scavenge nozzle valve present.
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
SECONDARY AIR DAMPER CONTROL:
AUX. AIR DAMPER AUX. AIR DAMPER OPEN CONDITION: (APPLICABLE TO AB, BC, CD, DE, EF, FG, GH, AND HH)
AUXIALIARY AIR DAMPERS CLOSING CONDITION (For El. AB)
1. Both FD fans are OFF2. Both ID fans are OFF3. Master fuel trip exists.4. Loss of unit critical power (+24V DC)
1. MILL A & B Off &2. No MFT &3. *Boiler Load index >30 % &4. EL AB back up trip
OR5. El. AB Started AND El. AB start time not expired
AND Boiler load is not >30%.
* Once the Boiler Load Reaches > 30% the aux air dampers close in a timed sequence starting from top with a time delay of 10 Sec provided all other conditions for closing are satisfied.
Also the auxiliary air control loop is tripped to manual if any of the following conditions exist. DP transmitter deviation high. DP transmitter failed. Furnace to Wind box DP very high (> 240mm WCL).
FUEL AIR DAMPERS (A-K) & OFA DAMPER OPENING CONDITIONS:
FUEL AIR DAMPERS (A-K) OPENING CONDITION
FUEL AIR DAMPERS (A-K) CLOSING CONDITION
1. Both FD fans are OFF2. Both ID fans are OFF3. Master fuel trip exists.4. Loss of unit critical power (+24V DC)
1. Post trip purge time expiredAND
2. ID fan off OR FD fan off OR MFT not exist.
Fuel (coal) air damper control loop will be tripped to manual if any of the following conditions exist:
Feed rate signal failed Open fuel air damper command (From FSSS) Close fuel air damper command (From FSSS)
*The opening command is removed once the post purge time has expired and all opening conditions are removed instantaneously for fuel air dampers F-K and for A-E with 30 sec time delay. The close command is extended with a time delay of 50 sec after the corresponding feeder is out of service.
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
ID FAN : ID FAN VFD CHANNEL-1 DRIVE START PERMISSIVES:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE
REMARKS
1. Ch-1 SRC Breaker Not Disturbed --2. Ch-1 SRC Breaker ON from SWGR --3. VFD Ch-1 No Alarm --4. VFD Ch-1 Ready --5. VFD Ch-1 Start Permissive Available -- From VFD6. ID Fan Ch-1 auxiliary Supply Healthy --7. Ch-1 No Fault --8. VFD System Aux Supply OK --
9. Reg. Damper Pos Min & I/L Gates Closed & O/L Gates Closed (OR) ID Fan VFD Ch-2 ON
10. Either LOP (A or B) ON --11. ID Fan Exciter Winding temp Not HI --12. Lub oil pressure OK ≥0.8 ata13. Fan/Mtr Brg temp. Not HI --14. Mtr Wdg temp. Not HI --15. Lub oil temp. at cooler O/L Not HI --16. Lub oil tank level Not LO --17. Flue gas path available OR Other ID Fan ON
ID FAN VFD CHANNEL-2 DRIVE START PERMISSIVES:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE REMARKS
1 Ch-2 SRC Breaker Not Distbd2 Ch-2 SRC Breaker ON3 VFD Ch-2 No Alarm4 VFD Ch-2 Ready5 VFD Ch-2 Start Permissive Available6 Ch-2 No Fault7 VFD System Aux Supply OK --8 Reg Damper Pos Min & I/L Gates Closed & O/L Gates Closed (OR) ID Fan VFD Ch-1 ON9 Either LOP (A or B) ON10 ID Fan Exciter Winding temp Not HI11 Lub oil pressure OK ≥0.8 ksc12 Fan/Mtr Brg temp Not HI13 Mtr Wdg temp Not HI14 Lub oil temp at cooler O/L Not HI15 Lub oil tank level Not LO16 Flue gas path available OR
Other ID Fan ON
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW ) VFD CHANNEL-1 TRIP PROTECTIONS:
SL NO
PARAMTR TRIP CONDN
ALARM VAL
TRIP VAL REMARKS
1) VFD Ch-1 FAULT /VFD2) Ch-1 SRC Breaker Elect Trip3) Fan/Mtr Brg temp V HI4) Mtr Wdg temp V HI5) Fan/Mtr Brg
VibrationV HI ≥9.9 mm/s
6) IDF-A Post Purge TRIP /FSSS7) Fan ON* for 120 sec & ID fan A
outlet gate 1 & 2 closed*VFD Ch-1or 2 min speed achieved
8) Fan ON* for 120 sec & I/L gate 1 & 2 closed
*VFD Ch-1or 2 min speed achieved
9) Both ID and both FD ON(off time delay 5 sec) & FD-A trip
FD to ID inter trip
VFD CHANNEL-2 TRIP PROTECTIONS:
SL NO
PARAMTR TRIP CONDN
ALARM TRIP REMSET VAL SET VAL
1) VFD Ch-2 FAULT /VFD2) Ch-2 SRC Breaker Elect Trip3) Fan/Mtr Brg temp V HI4) Mtr Wdg temp V HI5) Fan/Mtr Brg
VibrationV HI ≥9.9 mm/s
6) IDF-A Post Purge TRIP /FSSS7) Fan ON* for 120 sec & ID fan A
outlet gate 1 & 2 closed*VFD Ch-1or 2 min speed achieved
8) Fan ON* for 120 sec & I/L gate 1 & 2 closed
*VFD Ch-1or 2 min speed achieved
9) Both ID and both FD ON(off time delay 5 sec) & FD-A trip
FD to ID intertrip
ID FAN LOP-A:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE REMARKS
START PERMISSIVES1) Lub Oil Tank Lvl Not Low2) ID fan A LOP A MCC Not Distbd.
AUTO STARTLOP-B Tripped From LOP-B logicID Fan lub oil pressure low AND <0.6 ata 5 sec on delay
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
LOP-B ONID fan LOP order START AND LOP-B off
STEP#1 To be checked in SGC
STOP RELEASE1) ID Fan OFF 30 min. delay2) IDF-A LOP:B- ON & Lub Oil Pr OK ( > 0.8
ksc) AUTO STOP1) LOP order STOP STEP#55 To be checked in SGC
ID FAN LOP-B:
**Note: Same as ID fan LOP A.
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW ) FD FAN START PERMISSIVES:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE REMARKS
1 FD Fan OFF(From SWGR)2 Lube oil tank level Not Low Time Delay 2 sec3 FD Fan motor winding
temperatureNot HIGH
4 FD Fan Electric Trip Not Present5 Atleast One ID Fan ON6 FD Fan/Motor Bearing
temperature Not HIGH
7 FD Fan Control Oil Pressure OK >8ata8 FD Fan lube oil pressure OK <4 bar9 FD Fan Outlet Gate Closed10 Any of the LOP ON(MCC)11 FD Fan blade pitch Control Minimum(ACS)12 FD Fan blade pitch Control Manual13 SWGR Available14 SWGR not disturb
TRIP PROTECTION:
SNO PARAMTR TRIP CONDN ALARM VAL TRIP VAL
1 FD Fan post Purge trip From FSSS 2 FD fan /Motor Bearing
TemperatureVery HIGH T*+5 T*+10
3 FD Fan Motor Winding Temperature
Very HIGH T*+5 T*+10
4 FD Fan/ Motor Vibration Very HIGH 5 Both ID fan Off OFF(SWGR)
6 FD Fan ON (TD 5sec) AND FD Fan outlet Gate Closed
7 Both FD fan ON AND one ID fan OFF
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
FD FAN LOP-A:
S NO
PARAMETER REQ. STATUS
SET VALUE REMARKS
PERMISSIVE STARTPA Fan Lub Oil Tank Level Not low
AUTO STARTOther LOP Tripped LOP was running &OFF status appeared without
manual OFF command.Other LOP ON (TD 60 sec) & Control oil pressure LOW <5 barLOP Order start command When other LOP is OFF
STEP#01 To be checked in SGC
AUTO STOPLOP Order STOP STEP#54 To be checked in SGC
PERMISSIVE STOPFDF OFF (TD 30 min)Other LOP ON AND FD Fan Control Oil Pressure OK
>8ata
FD FAN LOP-B:
**Note: Same as FD fan LOP A.
FD FAN OUTLET GATE:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE REMARKS
PROTECTION OPEN:Both FD Fans OFF 15 min pulse
AUTO OPEN:FD Fan ON for (T sec)FD fan O/L gate open STEP#53 To be checked in SGCFD fan O/L gate open STEP#5 To be checked in SGCFD fan O/L gate open From FD fan B
logicAUTO CLOSE: (Permissive: FD Fan OFF)
Other FD Fan ON &Other FD Fan Outlet gate Open &FD Fan OFF
PERMISSIVE CLOSE:FD fan O/L gate close STEP#52 To be checked in SGC
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
FD fan O/L gate close STEP#2 To be checked in SGCFD fan O/L gate close From FD fan B
logic
PA FAN START PERMISSIVES:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE REMARKS
1 PA- Fan OFF(From SWGR)2 PA Fan control oil pressure OK >25 bar3 PA Fan electrical trip Not present4 Lub oil tank level Not less than min5 Path for PA fan Available6 PAF Fan/motor vibration Not high7 PAF fan/motor bearing temp Not high8 PAF motor winding temp Not high9 Any of the LOP ON10 PAF start permissive from
FSSS11 PA Fan outlet air gate Closed12 PA Fan Blade Pitch control
damperMinimum(ACS)
13 PA Fan Blade Pitch control damper
Manual(ACS)
14 Both of the FD fan ON OR (Either FD FAN On & Other PA FAN Off)
15 SWGR Available16 SWGR not disturb
TRIP PROTECTION:
SNO PARAMTR TRIP CONDN ALARM VAL TRIP VAL
1 MFT operated(From FSSS)2 PA fan /Motor Bearing
TemperatureVery HIGH T*+5 T*+10
3 PA Fan Motor Winding Temperature
Very HIGH T*+5 T*+10
PA Fan/ Motor Vibration Very HIGH 6.3mm/s 9.9mm/s4 FD Fan A AND B OFF(SWGR)
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
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PA Fan ON for 5sec AND PA Fan Discharge Air Gate Closed
*Actual Running Temperature observed
PA FAN LOP-A:
S NO
PARAMETER REQ. STATUS
SET VALUE REMARKS
PERMISSIVE STARTPA Fan Lub Oil Tank Level Not low
AUTO STARTOther LOP Tripped LOP was running &OFF status appeared without
manual OFF command.Other LOP ON for 30 sec &Oil pressure after filter (time delay)
<15 barTime delay 30 sec
LOP Order start command When other LOP is OFF
STEP#01 To be checked in SGC
AUTO STOPLOP Order STOP STEP#53 To be checked in SGC
PERMISSIVE STOPPAF OFF (TD 30 min) From SWGROther LOP ON from MCC AND PA Fan Control Oil Pressure OK
>25 bar
PA FAN LOP-B:
**Note: Same as LOP A.
PA FAN OUTLET DAMPER:
S NO
PARAMETER REQ. STATUS
SET VALUE REMARKS
AUTO OPEN1 PA Fan ON(Time Delay
2sec)2 PA Fan outlet Air Gate
OpenSTEP#4 OR 5 To be checked in SGC
AUTO CLOSE1 PA Fan Outlet Air gate
CLOSESTEP#2 To be checked in SGC
2 PA Fan Outlet Air gate CLOSE
STEP#52 To be checked in SGC
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
3 PA Fan Outlet Air gate CLOSE
From PAF B logic
4 PA Fan OFF (Time Delay 10sec)
From SWGR
SEAL AIR FAN A:
START PERMISSIVES SHUT DOWN CONDITIONS1. Seal air fan A start PB is pressed
OR2. Any PA fan ON AND Seal air header/Cold air DP
low for >10 sec
OR3. Auto Start Seal air fan A & not Seal air fan B
1. All PA fans off for 15 sec
OR2. Seal air fan A stop PB is pressed when
Seal air header/ cold air duct DP not low AND Seal air fan B stop push button not pressed AND Both seal air fans ON
OR3. Auto start Seal air fans A & B command
for more than 10 sec.
NOTE- One Seal air fan fails to start within 5 sec after receiving the start command; the other scanner fan will start automatically.
SEAL AIR FAN B: Note: Same as Seal air fan A.
SCANNER AIR FAN A:
START CONDITIONS SHUT DOWN CONDITIONS1. Scanner air fan start PB is pressed
OR2. No MFT AND Scanner duct/Furnace DP
low(<150mmWC) for 5 secOR
3. One scanner fan fails to start within 5 sec after receiving the start command; the other scanner fan will start automatically.
1. Scanner air fan stop PB is pressed whenScanner duct/Furnace DP low AND No MFT conditions are not present.
2. Both Seal air fans are tripped when Both PA fans are off for more than 15 sec.
3. Both Seal air fans are tripped when Both seal air fans have unsuccessful start command
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW ) SCANNER AIR FAN B:Note: Same as Scanner air fan B.
AIR PRE HEATER:
START PERMISSIVES For AH-A:
Sl No PARAMETER REQUIRED STATUS
SET VALUE
REMARKS
1. AH-A off2. AH-A Elect motor MCC not disturbed3. AH-A support brg oil temp Not V. High4. AH-A guide brg oil temp Not V. High5. AH-A supp brg LOP-A MCC not disturbed6. AH-A supp brg LOP-B MCC not disturbed7. AH-A guide brg LOP-A MCC not disturbed8. AH-A guide brg LOP-B MCC not disturbed9. AH-a power supply for air motor
solenoid valveAvailable
10. AH –A air pressure before air motor solenoid
Not low >5Kg/cm2
11. EP Path Available
AH ELECTRICAL MOTOR:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE
REMARKS
ON RELEASE:AH-A GB oil temp Not V.HI <70 oCAH-A SB oil temp Not V.HI <70 oCAH-A electrical motor MCC not
disturbAUTO ON:
AH-A SGC Startup Sequence Step#04 -- To be checked in SGCAUTO OFF: (Rel always available)
AH-A SGC Shutdown Sequence Step#53 -- To be checked in SGC
AH AIR MOTOR:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE
REMARKS
ON RELEASE:AH-A GB oil temp Not HI <70 oC
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
AH-A SB oil temp Not HI <70 oCAH-A Elect Motor OFF --
AUTO ON:AH-A Elect Motor Tripped -- 5 sec pulse
AUTO OFF: (Rel always available)AH-A Elect Motor ON --AH-A SGC Shutdown Sequence Step#53 -- To be checked in SGC
AH SUPPORT BEARING LOP:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE
REMARKS
ON RELEASE:Support Bearing oil temp HighSupport bearing LOP-A MCC not
disturbedAUTO ON:
AH SGC Startup Sequence Step#01 -- Either SB LOP ONTo be checked in SGC
AH ON ANDAH support bearing oil temp is high ANDOther Support bearing LOP OFF (2 sec pulse)
--
AH ON AND Other SB LOP ON for 30 sec ANDSB Oil flow LowAH ON & Other SB LOP ON to OFF
--
AUTO OFF: (Rel always available)AH SGC Shutdown Sequence Step#56 -- To be checked in SGCAH SB Oil temp
Low 30 sec delay, 5 sec pulse
AH GUIDE BEARING LOP:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE
REMARKS
ON RELEASE:Guide Bearing oil temp high HighGuide bearing LOP-A MCC not
disturbedAUTO ON:
AH SGC Startup Sequence Step#01 -- Either GB LOP ONTo be checked in SGC
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
AH ON ANDAH Guide bearing oil temp is high ANDOther Guide bearing LOP OFF (2 sec pulse)
--
AH ON AND Other GB LOP ON for 30 sec ANDGB Oil flow LowAH ON & Other GB LOP ON to OFF
--
AUTO OFF: (Rel always available)AH SGC Shutdown Sequence Step#56 -- To be checked in SGCAH GB Oil temp
Low 30 sec delay, 5 sec pulse
AH FLUE GAS I/L DAMPER(1 & 2):
Sl No
PARAMETER REQUIRED STATUS
SET VALUE
REMARKS
AUTO OPEN:AH FG I/L damper open OR Step#11 -- To be checked in SGCAH FG I/L damper open From AH-B
logicTo be checked in SGC
PROTECTION OPEN:AH-A ON for 5 sec AND MFT Operated
PERMISSIVE OPEN:AH SA O/L Damper open ANDAH SA I/L Path open ANDAH PA I/L Damper open ANDAH PA O/L Damper open ANDBoiler not ON.
AUTO CLOSE:AH Flue gas damper close Step#51 To be checked in SGCAH Flue gas damper close From AH-B
logicTo be checked in SGC
AH-A OFF AND AH-B AvailablePERMISSIVE CLOSE:
Both ID Fans off
AH FLUE GAS O/L DAMPER (1 & 2):
Sl PARAMETER REQUIRED SET REMARKS
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
No STATUS VALUEAUTO OPEN:
AH FG O/L damper open OR Step#10 -- To be checked in SGCAH FG O/L damper open From AH-B
logicTo be checked in SGC
PROTECTION OPEN:AH-A ON for 5 sec AND MFT Operated from FSSS
PERMISSIVE OPEN:Boiler fire not ON OR AH-A ON
AUTO CLOSE:AH Flue gas O/L damper close Step#51 To be checked in SGCAH Flue gas O/L damper close From AH-B
logicTo be checked in SGC
(AH-A OFF OR Tripped) AND AH-B Available
PERMISSIVE CLOSE:Both ID Fans off
AH PA I/L AND O/L* DAMPER:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE
REMARKS
AUTO OPEN:AH-A PA I/L damper open OR Step#5 -- To be checked in SGCAH-A PA I/L damper open From AH-B
logicTo be checked in SGC
PERMISSIVE OPEN:AH-A ON
AUTO CLOSE:AH-A PA I/L damper close Step#52 To be checked in SGCAH-A PA I/L damper close From AH-B
logicTo be checked in SGC
PERMISSIVE CLOSE:Both ID fans OFFAH-A FG I/L Damper 1 & 2 closed AND AH- B available AND (AH-A
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
OFF OR Tripped)PROTECTION CLOSE:
Both PA fans OFF From SWGR 900 sec pulse
* For PA O/L Damper control logic PA I/L Damper shall be replaced by PA O/L Damper.
AH SECONDARY AIR SCAPH-A I/L AND O/L** DAMPER:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE
REMARKS
AUTO OPEN:AH-A SCAPH-A I/L damper open OR Step#9 -- To be checked in SGCAH-A PA SCAPH-A I/L damper open From AH-B
logicTo be checked in SGC
PROTECTION OPEN:MFT Operated 900 sec. pulse
AUTO CLOSE:AH-A SA SCAPH-A I/L damper close Step#09 To be checked in SGC (Start
Sequence)AH-A SA SCAPH-A I/L damper close Step#52 To be checked in SGC
(Shutdown Sequence)AH-A SA SCAPH-A I/L damper close From AH-B
logicPERMISSIVE CLOSE:
AH-A SA SCAPH-A BP Damper openedAH-A FG I/L Damper 1 & 2 closed
**For SA SCAPH-A O/L Damper control logic SA SCAPH-A I/L Damper shall be replaced by SA SCAPH-A O/L Damper.
AH SECONDARY AIR SCAPH-A BP DAMPER:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE
REMARKS
AUTO OPEN:AH-A SCAPH-A BP damper open OR Step#9 -- To be checked in SGCAH-A PA SCAPH-A BP damper open From AH-B
logicTo be checked in SGC
PROTECTION OPEN:MFT Operated 900 sec. pulse
AUTO CLOSE:AH-A SA SCAPH-A BP damper close Step#09 To be checked in SGC (Start
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
Sequence)AH-A SA SCAPH-A BP damper close Step#52 To be checked in SGC
(Shutdown Sequence)AH-A SA SCAPH-A BP damper close From AH-B
logicPERMISSIVE CLOSE:
AH-A SA SCAPH-A I/L Damper opened ANDAH-A SA SCAPH-A O/L Damper openedAH-A FG I/L Damper 1 & 2 closed
AH SA O/L DAMPER:
Sl No
PARAMETER REQUIRED STATUS
SET VALUE
REMARKS
AUTO OPEN:AH SA O/L damper open OR Step#5 -- To be checked in SGCAH SA O/L damper open From AH-B
logicTo be checked in SGC
PROTECTION OPEN:AH-A ON for 5 sec AND MFT Operated
PERMISSIVE OPEN:Boiler fire not ONAH-A ON
AUTO CLOSE:AH SA O/L damper close Step#52 To be checked in SGCAH SA O/L damper close From AH-B
logicTo be checked in SGC
PERMISSIVE CLOSE:Both ID Fans offAH-A FG I/L Damper 1 & 2 closed AND AH-B available AND(AH-A off OR tripped)
COAL MILL
START PERMISSIVE FROM PLOS AUTOMMATIC MILL TRIP CONDITION FROM PLOS
1. Lub oil temp adequate (>30oC) 1. Both lube oil pumps are not ON for more
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
2. Lub oil pump ON for more than 60 sec AND lub oil pressure a cooler outlet is NOT LOW (>0.8 bar)
3. Lube oil filter not dirty (< 2 bar)4. Lube oil flow to gearbox is NOT LOW
(>200LPM)5. Any bearing temperature of gearbox is within
alarm limits (<75oC)
than 2 sec2. Lub oil pump ON and lube oil pressure is
< 0.5 bar after cooler is very low with a time delay of 15 sec.
3. Lube oil temp after cooler is very high (>65oC)
4. Lube oil flow to gearbox is very low (<175 LPM)
COAL MILL : Start Permissive1 Mill Ready Conditions 1. Pulverizer/feeder start permit
2. Pulverizer discharge valve open3. Pulverizer outlet temperature not high4. Cold air gate open OR Pulverizer ON5. Tramp iron hopper valve open6. Primary air permit OR Pulverizer ON7. Pulverizer no unsuccessful auto start8. All burner isolation valve open9. Feeder switch in remote10. Pulverizer no trip11. Lube oil system healthy12. Feeder inlet gate OPEN13. Bunker outlet gate OPEN.
2 Mill Start Permissive 1. (Nozzle tilts horizontal AND Air flow is less than 40% MCR) OR Any oil Elevation in Service OR Any feeder ON.
2. No MFT
MILL PROTECTIONS:1 Mill Protections 1. Pulverizer failed to start >10 sec
2. Loss of PA fan- trip pulverizer H, G, F, E3. Electrical trip4. Pulverizer discharge valve not open5. Pulverizer ignition permit is not available AND support
ignition required6. Hot air gate closed AND cold air gate not open7. Seal air to pulverizer differential pressure low ( <125
mmwc) AND Pulverizer ON for more than 60 sec.8. Any burner isolation gate not open9. Loss of primary air10. Loss of unit +24V DC
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
11. Lube oil system failed
2 Loss Of Primary Air Conditions:
1. PA HDR Pressure very low 2. All PA or FD fans off and any Pulverizer on3. PA HDR pressure low (TD 5 sec)
3 Description Of PA Trip: (Applicable to Mills H, G, F, E Progressive time Delay of 2 sec starting from Mill H for which, trip is instantaneous)
5 or more MILL on & any one of the following Any FD fan offAny PA fan not off
MILL HOT AIR GATE: OPENING PERMISSIVES: AUTO CLOSING CONDITIONS:
1. Pulveriser ONAND
2. Close hot air gate not presentAND
3. Pulveriser auto start-open hot air gateORPulverizer manual mode AND Hot air gate open PB is pressed
1. Pulverizer offOR
2. Loss of 24 V DCOR
3. Close hot air gate with 30 sec delay ##[Hot air gate not closed OR Pulverizer outlet temp 100oCANDClose hot air gate auto command OR HAG close pulse OR Auto pulveriser unsuccessful start OR (Feeder ON too 5 sec AND Feeder OFF)]
MILL COLD AIR GATE:
OPENING CONDITIONS: AUTO CLOSING CONDITIONS:1. Mill outlet temp adequate (90oC) AND pulveriser
is ONOR
2. Cold air gate PB is depressed.
1. Pulveriser ON AND mill Outlet temp is low(75oC)OR
2. Pulveriser OFF AND CAG close PB is pressed.
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
BCW PUMP : START PERMISSIVES:S N
PARAMETER REQ. STATUS SET VALUE REMARKS
1 Pump prot criteria Not present --2 Pump LP cooling water flow Not low >8TPH3 Diff Temp between BCW pump casing
& suction manifoldNot high < 50oC
4 Pump Motor Cavity temp OK >2oC &<63oC5 Pump Disch Valve Stem-1 Open --6 Pump Disch Valve Stem-2 Open --7 Pump Switchgear Available Remote & in service8 Boiler drum vent valves Closed --9 Pump Switchgear Not disturbed --10 CW supply to BCW pumps Normal Emergency CW tank
level OK
TRIP PROTECTIONS:
S N PARAMETER TRIP CONDN ALARM VAL
TRIP VAL REMARKS
1 Pump Motor Cavity temp V HI >63 oC 66 oC2 Pump Disch Valve Stem-1 Not Open -- --3 Pump Disch Valve Stem-2 Not Open -- --
PUMP AUTO START (in standby selection):
S N
PARAMETER REQ. STATUS
SET VALUE
REMARKS
1 Any other running BCWP (B OR C) Tripped --2 BCWP-C ON for 30 sec & DP low (5 sec delay) * (18 psi for >60% MCR)3 BCWP-B ON for 30 sec & DP low for 10 sec &
BCWP-C Not ON (2 sec delay)* (18 psi for >60% MCR)
ECW PUMP (BOILER): START PERMISSIVES:S N PARAMETER REQ.
STATUSSET
VALUEREMARKS
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PLANT INTERLOCK AND PROTECTION JPL (4 x 600 MW )
1 Boiler ECW pump suction header pressure Adequate2 Boiler ECW pump Suction Valve OPEN3 Boiler ECW Pump MCC Not disturbed > 2.5 Ksc 2 / 3 Logic(LVM)4 ECWP Selected Stdby & Its Discharge Valve Open OR
Its Disch.Valve Close
TRIP PROTECTIONS:
SNO
PARAMTR TRIP CONDN
ALARM VAL
TRIP VAL
REMARKS
1 ECW Pump ON and Off both commands from MCC
2 ECWP ON for 10 sec & Its Disch. Valve Not Open
TD= 2 sec
3 ECWP Disch. Hdr. Pr. V.HI4 ECWP Suct. Hdr. Pr. V.LOW
DIFFERENT LEVELS
DRUM LEVEL
( FROM HYFRASTEP )S No PARAMETER VALUE REMARKS
1 NORMAL LEVEL - 225 mm2 HIGH LEVEL ALARM + 125 mm 6th PORT FROM TOP3 HI HI LEVEL TRIP +250 mm 2nd PORT FROM TOP4 LOW LEVEL ALARM - 175 mm 6th PORT FROM BOTTOM5 LO LO LEVEL TRIP - 375 mm 2nd PORT FROM BOTTOM
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