ML17191B125
| ML17191B125 | |
| Person / Time | |
|---|---|
| Issue date: | 06/05/1998 |
| From: | NRC |
| To: | |
| Shared Package | |
| ML17191B124 | List: |
| References | |
| NUDOCS 9806110088 | |
| Download: ML17191B125 (52) | |
Text
25 Page 1 of~
OPL11*.ao8 leV. 0 I.
PIOCIWI:
BFll Licemed Opei-ator Training II.
SUBJBCT:
Licen*ed lequalification Training III.
TITLE:
Diesel Ceneratol"8 IV.
t.llJGTH OF LISS08:
8 houra Y.
OB.JICTIYBS A.
Tendnal Objective Upon completion of thi* l.. *on, the JlO/SRO will demon*trate satisfactorr knowledge of the di**el generatol"8.by *coring a liinimum of 8~ on a written exam.
- 1.
- 2.
- 3.
- s.
- 6.
Lut tbe Unit. 112 and Unit 3 dieHl generator ratings.
De*cribe th* lubricating oil system including the number of pump* and their purpose u dbcuased in claH.
Describe th* fuel oil 91*t* ineluding the number of pumps,
- their functi01W tnd* tbe location of* fuel ail *torage cai>>abilltiu.. cll*cua*ed ill clue.
Describe tbe*atarting air *J*U.* lu purpose and m.aaber of receiver tanks and pruaure rang.. u dlacus*ed in clue.
Describe the dieHl cooling water *Y*t* and explain bow it.
perforlUI it* purpoae as diacussed in clu*.
Describe the beat exchanger. operation and explain how the dieHl is maintained in atandby readineH u diacwised in clus.
- 7.
Stat* th* purpoee and operation of the turbo-charger.
- 8.
State the purpose of tbedi***l generator batterr and give it* ratings.
- 9.
State from electrical print. th* purpo*e and location of the instrumentation u*ociated with each diesel generator.
- 10.
List:
- a.
Diesel Cenerator Auto Start*
- b.
Di*Hl Output Breaker Closing Pec"111.ias1v***
- c.
Die**l Cenerator Trip* <*on-Accident Condition)
O*l6W 9806110089 980605 PDR MISC PDR 9806110092
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OPL17.\\.808 Bev. o
- d.
Di***l Generator Tripe (Accident Condition)
- 11. rrom electrical printa:
- a.
Describe the operation of the IJOBKAL/IKllCIDJCY lnfitch as diacuaHd in clua.
- b.
Identify all diesel generator starting points.
- 12. State the purpose and the positions of the diesel genet"ator Mode SVitcb.
- 13. rrom electrical prints:
- a.
List th* di***l generator start and atop sequence.
- b.
Describe a dieael atart and loading during an accident condition with and without normal power available aa dilCU8aed in clua.
- c.
Diacu1a equipment starts, tlmea, load ahedding and restarting u dilcusaed in clua.
- d.
lxplain how to place a unit 1n the diesel generator Back.feed llode u dilcus1ed in clua.
1.\\. Uat 10 41***1 generator: alaru and their: ~tpoints.
- 15. Di1cu11 the applicable Br& Technical Specifications aa discuaaed in clu1:
Section 3.9/.\\.9 V1.
TBAIIJIIC AIDS A.
Whi teboar:d and mar:ker:a B.
overhead pr"Ojector: and screen VII.
KA.TllULS A.
Handouts Brl TVA prints, latest E'W"ialon.
- 2.
VIII.
(
B.
Transparencies:
TP-1:
Figure 1. DIISBL CllJDATOB LUii OIL SYSTBll TP-2:
Figure 2. DIISBL ClllDATOI P'UIL OIL SDTlll TP-3:
Figure 3. DIISIL All START SYSTBll TP-\\:
Figure... DIISIL CllDATOI COOLIJJC WATD SYSTD TP-5:
Figure 5. SHUTDOWll BOAllD UllDllVOLUCI LOGIC TP-t.:
F"113'4"'* t.. T'fP*C A\\... D\\~~~\\.. G..ttll~~.,.~ 1)Q.ooP JWPUllJCES A.
BFIJ FSAI 8. 5 B.
BFIJ OI 82 C.
BFIJ TVA prints, latHt revidond
- 3.
45S767
- 4.
45S768 D.
BFrl Technical Specifications*
Section 3.9/.t.9
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{ -..ESSONOUTUE
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IX.
IITIODUC'l'IO&
'rhi* l***on reviewa the di***l genet"atoC'8 and their awcili&rJ equipment in detail.
X.
t.ISS08 BODY A.
Ceneral De*cription
- 1.
Di***l Generators
- 2.
- a.
11ght"(8) diesel genet"ators, 4.ahared bJ Units l and 2 and 4 for Unit 3.
- b.
Ratings
- c.
v 1 and 2 n
(1) 4160 v, 3 **
4160 v, 3+
60 Hz 60 Hz (2) 2600 kW 2600 kW for continUowa ccmti1WOUS (3) 2850 kW for 2850 kW for 2000 boun 2000 hour&
(4) 2950 kW for 2950 kW for 7 day*
7 da:r*
(5) 3050 kW for 3050 kW for 30 ainu.tea 30 ainutea capable of fut *tart and ready to accept load within 10 **cond8.
Diesel Generator Awciliariea
- a.
Lubricating oil (Figure 1)
The engil)e lubricating oil *:r*tem i* a combination of four.uba:ratema:
th*
main lubricating *:ratem, the pi*ton cooling *:r*t~. the *cavenging oil
- r8tem, and th*
NS'TRJCTCA NOTES
- Obj. V.B.1.
Obj. V.B.2.
.(
- SSONcun.N!
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- oakback lube oil syetem.
The main oil pump, piston oil pump, and *cavenging oil pump are engine driven.
(1)
Th*.. in lubricating oil *Y*tem 8uppli** oil under preesure to the variOU8 moving part* of the engine. The main lube oil pump take* oil from the *trainer bou*ing and discharges it into the main oil manifold, from tlhich the *in bearinge., gear train, turbocbal:"ger, cam abaft, and other moving parta are wpplied.
(2)
Th* piaton cooling s1stmll suppliea oil for piston cooling and.lubrication of the piaton pin bearing wrface. The pump receive* ita oil from a common wction with the main lube oil pump and dalivara oil.to the two piaton oil cooling manifolds to supplf the piatona.
C3)
'fba acavanging oil *JSt*
supp11H tba other *Y*tca with cool~. filtered oil. Th*
acavanging oil pump take* a wction from tbe*engine oil pan and discharges the oil through th* oil f iltar and the oil cooler to th* strainer houaing to supply th* main oil pump and th* piaton oil pump.
(4)
Th* aoakback pump is.motor driven. It pNlubea the turbocharger bearing area ao that.
the bearing will be fullJ lubricated tlhen the engine receive* an automatic atart signal. It also nmovH residual beat f roa the turbocharger bearing area upon *butdown of the engine.
The soakback oil pump also circulate* warm oil through the oil system via a 30 psig check valve and keep* the engine in a constant state of readinH*
tor an immediate start.
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.ESSCNCUTUE
- l.
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- b.
Puel oil *J*tem (Figure 2)
Cl)
During *tart action, the electric driven priming pump 8Upplies fuel oil to th* injection eyatem.
(2)
Th* unit normallJ operate* with the engine-driven fuel oil
- J*t*, with the motor driven u backup.
Both *19teu operate
- imultaneou*lJ with the motor-driven *Y*tem bypaaaing the engine fuel injectora and retunli.ng fuel to the day tank.
(3)
The 550 gallon "day" tank provi4$.. enough fuel to operate for 2-1/2 hours of full load operation.
(4)
Fuel m8t be tnnaferred from the 40,000 gallon 7~J ~ieael atorage tank with the di***l oil*
tnnafer pump to contima*
operation. Thi* la accompliahed matomatically by level avitchea on the "day" tank. The 7~y atorage tank capacity i* required by Technical Specification*.
(5)
An emergency fuel cut-off valve in th* engine-driven fuel oil ayat* 18 provided in event of a fire or other emergency.
(6)
Tranafer pump* are provided Which can *8Ul'PlJ fuel oil from th*
2-71,000 gallon auxilial"J boiler fuel oil tanka to th* 7-day ator-ase tanka.
- c.
Starting air ayatc (Figure 3)
Cl)
Two full1 redundmlt air *tart
- yat-. per di***l are provided, either of Which i* capable of dieHl atarting.
TP-2 Obj. V.B.3.
The motor driven pump will still aupply fuel oil.
TP-3 Obj. V.B.4'.
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(2)
(3)
(5)
Receiver preaaure in each bank of unite 18 maintained at 175 to 200 pdg bf air compreHon.
Air campreHor At: 110tora are potMred f l"Oll the 480V AC Dieael Awc11iaey Boarda, tb* DC 110tor
!t"'ml the 250V DC Battery Boarda.
lacb *f*tem drives 2 fully capable air *tart 110tora which are engaged and E"Otat* the engine when.air is muppli*d by tbe
- olenoid *tarting valves.
- At >100 rpm the *tarting *olenoid valve ia deenergized, interrupting air to the *tarting 110tora and venting tb* prea8Ure off.
(6)
Thi* C.U.** tb* air 110ton to
- top and di*engage.
C 7)
If 91*t* pre*.ure *i* redaiced to 175 p*ig, sufficient pre*8Ure nmaiu to *tart the 41***1 generator once vitb no air compre**or action.
- d.
Cooling water *Y*tem (Figure 4)
(1).
Cooling water circulates through cored puaagu in the Cflinder linera and heads and the after cooler on the turbocharger.
(2)
A conatant temperature b maintained bf a tcpera~
regulating valve Which control&
th* flow of engine cooling water through the heat excbangera.
(3)
A bJPaH line provide* fut
- varmup and a con*tant flow of engine cooling water.
(4)
Heat exchanger cooling i*
provided bJ the DCW Sy*tem.
2S° Page 7 of~
OPL174.808 Rev. o IG'TRJCTOR NOTES
- .,i**
- i.
TP-4~*:.
Obj. V.B.S.
- Obj
- V. B. 6 *
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- 2S Page 8 of -N.
OPL174.808 Bev. o (S)
Lube oil la alao cooled by the.
di***l cooling water *Y*tem.
(6)
An expanaion tank provide* a wrge volume and makeup capability.
(7) tWo gear driven centrifugal pumpa provide th* motive force.
(8)
A 151cW ialeraion heater ia provided to maintain the diesel in *tandby readi~eaa (warmed).
(a) 8atural circulation will force the cooling water through the *1*tc.
(b) 1\\arbocharger The oil cooler now becomes an oil "heater* and the flow from the oil c1rculating pump 18 warmed to bep the.oil *18t* in
- t&ndbJ readln****
(1)
Th* dieael ia turbocharged to force IDOre air into the engine, increuing the power of the engine.
C2)
- The turbocharger ia driven by the engine gear train at low loada and bJ exhawlt gaa at high loads
(>7~).
(3)
An aftercooler reducea th*
temperature of the air, increaaing iudenait1 and allowing 110re oxygen to be forced into the engine.
- f.
Di***l generator control power Cl) 12SV DC battery *1atc, with battery and a normal and alternate battery charger
- ~NOTES.
Obj *. V.B.6.
Obj. V.B.7.
Obj. V.B.8.
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(2)
The battery charger is supplied from the *aov Di***l Auxiliary Boards.
(3) 60-cell: 12.5 ampe for 8 houre 25.3 ampe for 3 hour3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br />'8 50 ampe for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> 1*8 ampe for 1 minute Located in th* Di***l Cenerator aoom
. (5)
SUpplie* p0wr for:
<a>
Dieeel contl"Ol/logic (b)
Governor boo*t*r pumpe (c)
Fuel pump (d) rield fluhing lela1 protection (f)
- kV degraded-voltage rela1*
B.
Iutl'\\lllefttation
- 1.
Contl"Ol aoom, for each diHel, and dieeel contl"Ol panele
- a.
Synchl"Onizing equipment
- b.
lndicaton for voltage, current, llil, llVAI are pl"Ovided for each diesel.
- c.
Voltage and cur'1'81lt loade on each bue, board, and breaker an pl"Ovided.
2~
All Contl"Ol loom equipment and contl"Ol8 are duplicated for individual diesel*, buae* or board* at the nepective *tv Shutdown Boarde.
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OPL17.\\.808 Rev. 0 NSTRJCTCR NOTES Obj *,, V. B. 9.
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OPL17.\\.808 aev. o
. ( -.ESSONCUTUE
- 3.
Centr'al Information Panel
- a.
Located in Dieael Generator Building
- b.
Pr.. enta dieHl loading information
- c.
Coamunication center to monitor load, dispatch supervision vben dieaela are on backup control Interlocks
(....
(
- a.
Diesel generator auto-atart dgnala Cl>
High drywell pE"eaaure 2.*5 psig, (from Core Spray logic)
(2)
Low-lov-lov reactor water level
-11*.5", (from Core Spray logic)
(3)
Lo** of voltage to *kV Shutdown Board (Figure 5) :
Degraded voltage on *kV Shutdown Board (Figur:9 5) mil. On (1) and (2), all dieHl generator. will etart.
On (3) and <*>, only the d!eeel aeeociated with th* board(a) loaing voltage will etart.
- b.
Dieael output breaker will cloae only if:
(1)
Dieeel baa *tarted and ia up to epeed (2)
All other eupply breaker. to the
- *kV board are open (3)
So eupply bE"eaker overcurrent lockout exillt*
An undervoltage exi*t* on the board Nl1'RJCICR NCT'ES
- Obj. V.B.10.a.
TP-5 O volta.
- TP-5 3920 volts Obj. V.B.10.b.
(
- c.
Dieael generator trips (1)
High differential current (2)
OVel"Current with voltage r"e*tl"&int (3)
Lo** of field CS)
OVenpHd (1035 rpm
- 115~)
IQI!:
Under accident conditiona only items (1) and (5) will cauae a trip.
C.
Operational SUlllmal"J
- 1.
- 2.
Di***l Genel"&tor Controls
- a.. With the DIG lmel"gency Control.Tran*fer SVitch in llOBllAL, auto *tart and
- "Control Room aanual *tal"t* an provided bJ th* normal bus.
- b.
With the lliel"gency Control Tnn*f*r SWitcb in lllDGBllCY, the di***l can be 111UW&l1J *tarted and controlled from it* *kV Shutdown Board; auto-atart capability *is available.
Remote Starting from the Control Room
- a.
All dieeela (Units 1/2) can be
- ilultaneoualy *tarted from Unita 1 or 2 Panel 9-8 with the dieael Start witch.
- b.
Panels 9-23-7 and -8 are provided* vi th individual dieael Start, Stop,
- ynchronizing equipment, and lmet"gency Stop featurea.
~5 Page 11 of "2'4.
OPL17*.aoa aev. o INSTRJCTCR ~s Obj. v.a.10.c.
Obj. V.B.10.d.
Obj. v.a.11.a.
Obj. V.B.11.b.
- r.
- 2~
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.ESSONCUTUE
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- c.
Remote *tarting is available from 4kV Shutdown Boards *
- d.
lacb of theH *tatiom bu the following control svitche*:
(1)
Start-Stop switch (a).
Start initiatea fast start of die*el generator.
(b)"
Stop-8eutt"&l position, initiates normal *top aequence (He below) if.
placed in Stop and pulled*
out.
Cc)
Reaet poaition to naet Auto Start lockout.
Operational llode SVitch..
Seta iDode of voltage ngulator operation.
- To l.nitiate modes li*ted below *. place switch in position and pull out.
(b) ingle Unit*- Seta voltage ulator for diesel lying 4kV Shutdown*
only *ource.
Cc)
Units voltage gulator for operatin die*el generatora in parallel.
(d)
Parallel wit Sy*tem -
Seta voltage gulator to parallel w1 th e of th*
4kV Unit Boards ia the 4kV Shutdown Bua mi: Any fut*
- signal, or automatic, plac a voltage ngulato in Single Unit.
Obj *. V. B. 12
- ll
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(ai) SINGLE UNIT-Ustd whtn tht 9tntraitor is th* onllJ suppllJ to th* usociaittd shutdown boaird. Spttd (frt~) droop (dtcrHSt) from Ztro loaid KILO\\rr'ATTS to full nttd loaid KILO\\rr'ATTS ts ltss thain on* ptrctnt. (Fi9urt 6A).
Voltaigt droop from ztro loaid OUTGOING KILOVARS to full raittd loaid OUTGOING KIL.OYARS is ltss thain on* ptrctnt. (FiCJUr* 68)
. AnCJ fut st.rt si9nail or DC control powtr loss aiutomaiticailly plaicu th* modt of optraition to SINGLE UNIT mod*, without li9htin9 tht indicaitor aibov* tht SINGLE UNIT position. Rtq¥dltss of stairt si9~1 tvP*, pulling up tht MODE SELECT haindle and plaicing it in tht dtsirtd positior:i will chain9t tht modt of optr1tion aind liqht up tht usociaittd indic1tor uovt tht MODE SaECT switch.
(b) UNITS~ PARAUn. - Used whtn two C)tMr1tors r* to bt titd to9fthtr. Spttd and vo1t19* droop air* idtnticail to SINGLE UNIT modt. 8ruktr positions *r*
- StnStd to dtttrmfnt tf th* untt ts optr aitfn9 fn pair* ll* 1 with *nv of th.. othtr 7 dits.1 9fntr1tors. If so, fttdb1ck occurs bttwHn spttd r*9ulaitor-s (*nd volt19e rf9Ulltors) of th* pv111tltd 9fMr*tor-s so ~t stult loaid shll"ing optraition nsults.
Pai9t 12-A -of2S 0Plt74.W8 Rtv.O (c) PARALLEL YITH SYSTEM - Ustd whtn 9fntraitor is to bt pvailltltd with offsitt powtr. To tnSUr* stlb1t 1Hd w1"in9 with Vid, spffd droop from nro loaid KILOYATTS to full nt.d loMI KILOYATS ts 1f>proxirNttllJ flvt ptrctnt. (Fi9un 6C)
Volt* droop from ztro lold OUTGOING KILOV ARS to full nttd loaid OUTGOING KIL.DY ARS is aipproxirnaitt ly flvt ptrctnt. (FiCJUr* 6D)
(3) Govtrnor Control Switch (FiCJUrt 6 A or 6C)
(1) lncrHSt KILOY ATT loaicft\\9 whtn pM"ailltltd to offsitt powtr.
OR (b) lncr*u* output fnqu.ncv whtn 9.n.r1tor is tht only supply to 1 boaird.
R1isn volt19* droop curvt (tncrtues current in f"wld windings) to tither: (Fi9UI"* 68 or 6D)
(1) lncrtut tht OUTGOING KIL.OVAR 1o1din9 whtn pairailltt.d to offsitt powtr.
OR (b) lncrtut output volt19t when 9tntntor ts tht only supply to tht boaird.
- 3.
L
(
... l *
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Voltage regulator cont~l.vitcb reue, decreue (4)
(5)
In addition, dieael Start/Stop and wanu*l field fl.. b control*
are available at tbe dieael gener"ator cont~l panel for eacb dieHl.
l2lJl. Tb* di***l geneNtor logic
- panel mat be deen*rsized to uae the** cont~l1.
Di*Hl GeuNtor Start/Stop Sequence
- a.
The air *tart aequence la outlined below:
- (1 >
One bank of dual air *tart in&
- ton (dependln& upon whicla bank
- la Hlected for-prefen'M *tart>
cnna the englM. If the -am fail* to *tart (<40 rpm 1D 3 eecond8 or- <100 rpa 1D
- Hcanda after *tart *1paal), the air
- tartlDs *ton *but c1own.
After a 1/2 Hcond pause, botb banka of dual air *tartlng mtora crank tbe engine. If the engine fail* to *tart, tb* air *tarting
. *ton *but dow and prefened bank la locked out.
After a 1/2 Hcond pauH, the other.bank (bank not Hlected..
pref er-red) cr-anb tbe engine. If tb* engine fail* to *tart, U.
air *tarting *ton *but down and the *econd bank la locked out.
(2)
At 870 rpa tbe break9r clo**
dgnal la a ~rmiil*i,,.. Bl"Mbr clo.ure al*o.recauirea:
(a) ill other aupplJ brubn open
.2~*
Page 13 of N OPL174.808 Rev. 0 N9TFIJCTQR NOTES Obj. V.B.11.b.
Obj. v.a.13.a.
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OPL174.808 Rev. o (b)
Cc) 80 oven:urrent lockout on eupplJ breakena
.undervoltage or degraded voltage on 4kV board
- b.
Stop *equence Cl)
Placing Stop.vitch to Stop and pulling up initiates *top
- equance.
(2)
Ca)
Di**~l will idle to 450 rpm and tdpa after 11.S minute ttme dela7 to allow dieHl to cool.
(b)
After trip, die*el i* aet f_or auto operation.
Cc>
°"ring tiM dela7, an1.
fut *tart 8igna1 will re*tart the die*el.
llllergencJ Stop (Control loom panel8 onlJ) will *but off fuel oil to i.Ajectol"8 tor ilamediate
- top.
Ca>
on11 to be used 1.n cue*of local fil"'e, or low-low lube oil prH.ure (b)
Puel oil flow coola the fuel injectors. which 11&7 be dUl&ged.
Accident Operation
- a.
Accident dgnal received Cl)
Signal* diH*l generaton to *tart C 2 >
Open* diHel output breabn if clo*ed
- b.
If norm&! volt.age available, load will
- equence on u follOW8:
Obj. V.8.13.b.
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OPL174'.8D8 Rav. 0 e (
ESllCNCUl\\H!
I Nl1RJCICR liOl'ES
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Time After Accident Slmal O aec.
7 HC.
1" aec.
21 HC.
28 HC.
_....£ IJDl, CS, IHI, CS IHllSW*
IHllSW*
SID loud
.IHll, *cs IHllSW*
SID Board
.Q mm, cs llHRSW*
- IHBSW for ucw TiM Alter
- c.
~f nonaal power la not available Cl)
After a S **cond T.D., all.\\kV Shutdown Board load11, except
.\\kVl.\\IOY tranaformer breakers, are auto tripped.
(2)
Dieael generator output breaker cloaea when undervoltag*
penU.aaive 1a received.
(3)
Lo&da aequenc* u iluH.cat.ed below:
Di.. el Pwr SID loud Anilple. ___&.
SID Board B
S/D Board SID Board c
---R O aec.
7 aec.
1" aec.
IHI cs IHJlSW
- s.
IHll IHI IJDl cs cs cs IHISW IHllSW IJDlSW Back.feed Operation Provided to allow f *eding die11el generator power back to unit boards in order to atart a ccw pump and eatabl111b tb* main condenaer u a beat aink following a loH of all incoming powr.
- a.
On Panel. 9-23, there are two back.feed SVitcbe*, one for ucb.\\kV Shutdown Bus.
- b.
Placing tbeH nitcbn in BACDllD will trip and lock out tb* nonaal and alternate supplJ breakers on the u11ociated unit boudll and allow cloaing on* of tbe feeder breakers to a unit.board fl"Olll the ahutdown bus
- Obj. Y.B.13.c.
Obj. Y.B.13.c.
.I*
Obj. Y.B.13.d.
- t.:.
- j:
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OPt.1'7.\\.808 Rev. 0
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WSCHCUTUIE
- 6.
- c.
BJ paralleling two dleaela to a *kV Shutdown Bua (unit. in Parallel llode),
.a CCW pump and conden8ate pump can be 1t.arted on a unit board to provide a hut aink and to wpply &akeup to th*
- reactor ve11el. **fer to OI-82 for procedure to parallel the dieeele.
- a.
-.Ot auto'"
Cl) lither air compreeaor 8Witches not in auto (2) rield breaker not cloeed (3)
OVerapeed trip lever not reaet
- b.
"'Low oil ;nauure" (1)
.Alana at 20 pal 1f engine 'Peed ii betwMn ioo rpm and 870 rpm (2)
Alarm at.. pal 1f engine speed i1 above 870 rpm
- c.
"Bl crankcue preawre'"
Alarm at 1 to 1.7 _in. - H20 crankcue pre*aun
- d.
'"Low cooling water preeau""
Alana at 20 paig
'"Low raw water pre1sure'"
Alarm at 7 plig llcw aupply to heat excbmlger
- f.
"Circuit malfunctiona'"
.. ~.. :
(1)
Alarm at 12 minutee after 1top aignal* if all rela19 are not reeet (2)
Cenentor voltage le** than 75~
11x Hcond* after puaing 100 rpm on fut start Obj
- V. B.14 *
( ***
(
- g.
"IJo field" Alarm 1f field voltage not normal aix aecond8 after atart
- b.
"Low air prea8W'a" Alarm at 165 paig air preall\\U"e (di1abled during cranking of angina)
- i.
"Start failure" Cl) rut atart relay not picked up within one aacond after atart aignal
- (2 >
lngina.,.ad below *o rpm three aacond8 attar atart aignal (3) lngine epffd above 40 rpm but leH than 125 rpm four a.-cond8*
after *tart.. ignal j.
"""4!1 traafar abnormal*
Alarm when level ln day tanJc drop* to 190 galloua or riaea to 497 gallona Jt.
"Fuel preaaure abnormal" Alarm when fuel preaaure reaches 51 paig
- 1.
"Hot engine" Alarm when cooling water temperature reaches lto*r
- a.
"Lov lube oil tamp'"
Alarm when lube oil temperature drops to us*r witb engine apead below 100 rpm
- n.
"DiaHl engine atoraga*tanJc level abnormal" (fuel oil)
(1)
- Alarm at 9~ high level (9~
indicated level i* 96.n of tank volume - *39,000 gallona) z Page 17 of It OPL174.808 Rav. 0 ttS'TRJC'TCR NOTES
~...
...l c**\\
ii\\
'l I
(
- Oi'l.l.7..\\
- BOB llev. O (2)
Alarm at 75~ low level (75~
indicated level ia 81.7'. of tank volume - -3*.ooo gallona>
D.
Operational Conaiderationa OI-82 cautiona th* operator to avoid routine fut
- tart* between 15 ainutea and 3 boura after" engine abutdow.
- 1.
- 2.
- 3.
During theae condition*, the aoakback ayatem and the illDeraion beater 1n the cooling water *1*tem maintaina the oil ayatem l"eady to aupport 'automatic *tarting. However, if the engine receive* another atart signal before the oil ha9 bad time to cool, the full output of th* circulating pump will flow only to the turbocharger du* to reduced flow reaiatance in thb portion of the ayatem created bf the lower vbcodty of the hot oil
- The circulating pump will not be ale to develop 30 peig diacharge preesure, ao no oil will be aupplied to the ayetem.
8099 of the oil contained in the filter and cooler wil~ 4ra1n back to the ausip via the lube oil acavenging pump, and aome of the oil ill tbe
- trainer box will be dravn into the cooler by the vacuum that developa.
Then, if a fut atart signal ia received, the oil diacharged from the main oil PumP mat replace tbe drained oil before any oil can reach the turbocharger.
Under the wol"tlt conditions, the engine may actually.reach operating.apeed before oil pr-eaaure is eatabliahed at the cause aome smearing of th* bearing metal ao that cumulative dulage f roa HV*ral aiailar atarts wuld r-e1Nlt in turbocharger failure.
I.
1'edmical Specificationa Sectiona:
3.9.A, 8, C; *.9.A, B Obj
- Y. B. lS.
C.
During th.is lesson we have diecu.sed the Unite 1/2 and Unit 3 diesel generators and aux111arr equipment in detail.
Page 19 of OPLl74.80S Rev. o
. NSTRJCTCR NC
-~. ---~ --
7 lDNLllEPRESSlH~
SCAVENGHl
- =stWT cif c
1UBX>WGR ii1 -
LUBE OR.FLTER 0 iii TO MAIN BEARINGS, Cll m
GREAR TRAIN, CAMSHAFT r-ROCKERS a
m z
10 CVlN)ERS m
- D
?i 0
- D PISTON Oil PUMP
._MAIN Oil PUMP c m (SHAFT DRIVEN)
(SHAFT DRIVEN) m Q
UJeEOL r-lUB)QWtGB>e<<;tE Cooler Cll
~
OILCIRCPUW iC (M)TOR DRIVEN)
STRAMA FLTERS
~~
Page 21 of~
OPL 174.808
(.
Rev. 0 1
i I
if h
~
0 --
~
I~
LI.
~
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c:
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1 1
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- .~~
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Q
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- C'
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5 :.:
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Figure 2.
DIESEL GENERATOR FUEL OIL SYSTEM
-(
(
FE.1EF VAL.VE AIRLINE WSACATCA SCUNOIDAIR VAL.VEWl'TH Dut.tPWHT AIR STARTING MOTORS sa..aa>
STARTING VALVES AIR cu.GE STFWNER R.EXJBLE CCNECn:NS
'TYPICAi. AIR STARllNG ~DIAGRAM AC MOTOR!
cc~*
DAVEN CXIM"'fEER Figure 3.
.DIESEL AIR START SYSTEM FEUEFVAL.VE UNIT 3 ONLY
j ENOK SIGHT GAGE I
- CVLH>ER LM.RS
- 2. CVLH>ER I-EADS J.TIJUIOCHARGER DISCHARGE AIR COOLER
~
VE.NT LR YATER
£>
£RAT\\JRE REOll.ATINO YM..Vf. I-EAT__/ EXCHANGERS FROH EECY TO YARD (tYS DRAINAGE i * (JI CLOSES ON LOSS Of VOLT AGE FOR I. :5 SEC. lll>EfMl.TAGE RELAYS 27DA 27 27DAXIDAV N;f;.ll)(NT SIDNM. U-I, 2, OR 3 START 0/0 DEORADEI> VOl.TAOE RELLAVS 2-211-1 A INST. PICk lP TDOO.3SEC. -211-2A TOPU 4SEC. 213 CLOSE FOR OYERYCJl T AGE 4400Y FOR:SSEC. ..-----127 SAX/SAY TRPS NORMM. TRPS AK> M.L M.TERNATE FEEDS MOTORS D/O lP TO SPEEDI ux::dlrs I ~ (86) ~ M.L FEEDER I BREAKERS OPEN., _____ 213 OYEiM1.TAGE RELAYS TOPU 5 SEC. Nft.ltCIATIJN CLOSE 0/0 BREAKER ( * ( ~ ~ IOt--~~~~~~~~~~~~ I 0 KW 6A Speed Droop SINGLE UNIT, UNIT IN PARALLEL ICW 6C Speed Droop PARALLEL WITH SYSTEM I! Page 25 of 25 OPL 174.808 Rev. 0 .J *llOt---------------- ~ 0 68 KVAA OUTGOING RA'TED (LAO) Voltage Droop SINGLE UNIT, UNIT IN PARALLEL
- j o'-------------------------i--------.,
KVAA OUTQOINQ RATED (LAO) ID
- Voltage Droop PARALLEL WITH SYSTEM Figure 6.
TYPICAL DIESEL GENERATOR DROOP CURVES !1 SYSTEM: 264000 Emergency Generators (Diesel/Jet) INPO
REFERENCE:
264 Emergency Diesel Generator System INPO
REFERENCE:
265 Gas Turbine Generator TASK:
Perform a lineup of the diesel generator system Start a diesel generator (DIG}
Load the diesel generator (D/G}*
Monitor the diesel.generator Unload the diesel generator Shutdown the diesel generator (O/G)
Transfer fuel oil from main storage tanks to various system tanks Operate the diesel starting air compressor Restart a diesel generator (D/6} with an automatic start signal present Perform emergency diesel generator (EOG) load tests Perform lineups on the gas turbine generator Start the gas turbine generator rerrotely Monitor gas turbine generator emergency start Monitor the gas turbine generator during operation Conduct normal shutdown. of the gas turbine.generator Conduct emergency shutdown of the gas turbine generator K/A NO
- Kl.
KNOWLEDGE IMPORTANCE RO SRO Kl. 01 Kl.02 Kl.03 Kl. 04 Kl.OS Kl.06 Kl. 07 Knowledge of the physical connections and/or cause-effect relationships between EMERGENCY GENERATORS (DIESEL/JET) and the following:
A.C. electrical distribution.......................... 3.8 D.C. electrical distribution...***..***.**......**.*.. 3.3 Fire protect ion system.............................. *.
- 2. 9 Emergency generator cooling water system *.**.*....**.. 3.2 Emergency generator fuel oil supply system ******..**** 3.2 Starting system......*.*.....*.**.***.*..*.*..**.****. 3.2 Emergency core cooling systems........................ 3.9 K2.
Knowledge of electrical power supplies to the following:
K2.0l K2.02 K2. 03 K2.04 K2.05 K2.06 K2.07 Air compressor........................................
Fuel oil pumps........................................
Turning gear (jet engine}:
Plant-Specific **....*.*..*
Ignition system (jet engine}:
Plant-Specific.******.*
Lube oil pumps...................*...............*....
Battery charger..................*.**.***..*....*****.
Emergency generator field flash................... ~...
Kl.
Knowledge of the effect that a loss or malfunction of the EMERGENCY GENERATORS (DIESEL/JET) will have on
-fol lowing:
KIA catalog: BWR
- 3.6-9 2.2*
2.2*
2.0*
2.3*
2.3*
2.2*
2.1*
4.1 3.4 3.2 3.3 3.3 3.2
- 4. 1 2.4*
2.4*
2.3*
2.7*
2.4*
2.2*
2.3*
SYSTEM:
264000 Emergency Generators (Diesel/Jet)
Tasks as noted previously K/A NO.
K3. 01 K3.02 K3.03 k4.
K4.0l K4. 02 K4.03 K4.04 K4.0S K4.06 K4.07 K4.08 KS.
KS.01 KS.02 KS. 03.
KS.04 KS.OS KS.06 KS. 07 K6.
K6. 01 K6.02 K6.03 K6.04 K6.0S K6.06 K6.07 K6.08 K6.09 KNOWLEDGE IMPORTANCE RO SRO Emergency core.cooling systems..*.*.........*......... 4.2*
4.4*
A.C. electrical distribution.......................... 3.9 4.0 Major loads powered from electrical buses fed by the emergency generator(s)............*................... 4.1*
4.2*
Knowledge of EMERGENCY GENERATORS (DIESEL/JET) design feature(s) and/or interlocks which provide for the following:
Emergency generator trips (normal)....................
Emergency generator trips (emergency/lOCA)......*.*...
Speed droop control....*..*.*.....*....*.*..........*.
Field flashing..*.*****..*....*. *...........*....*.*....
load shedding and seq~encing..........*......*.*.*...*
Governor control.~.....*...................*..........
local operation and control...***.**********..********
Autornat ic startup.....................................
Knowledge of the operational applications of the following concepts as they apply to E"ERGENCY GENERATORS (DIESEL/JET) :
Definition of frequency and synchronous frequency~ **..
Reactive power contra l................................
Real power control......................................
Governor control...... *................................
Paralleling A.C. power sources........................
Load sequencing.......................................
Speed droop...*.*....***...*..*..*...*****.**.........
Knowledge of the effect that a loss or malfunction of the.following will.have on the EMERGENCY GENERATORS (DIESEL/JET) :
3.S 3.7 4.0 4.2 2.S 2.7 2.6 2.7 3.2 3.. S 2.6 2.7 3.3 3.4 3.8 3.7 2.0*
2.1
- 2.0*
2.1*
2.4*
2.4*
2.4 2.S 3.4 3.4 3.4 3.S 2.3 2.4 Starting air...**...*..*..*.......*..**.*..*....*...... 3.8*
3.9 Fuel oil pumps.......................*....*. -*..*...... 3.6 3.6 Lube oil pumps.............................*.......... 3.5 3.7 Turning gear (jet engfoe):
Plant-Specific............ 2.S 2.S Ignition system (jet engine):
Plant-Specific.....**.. 2.S 3.0 Battery charger *......**.......*..*....**.*.**.*.***.. 2.9*
3.1 Cooling water system..*....*.*.**..*.***.**...******** 3.8 3.9 A.C. power.....................................**..... 3.6 3.7 D.C. power..*........*...........*...****..*****.***** 3.3 3.s*
KIA catalog: BWR 3.6-10
SYSTEM:
264000 Emergency Generators (Diesel/Jet)
Tasks as noted previously K/A NO.
ABILITY Al.
Abfl ity to predict and/or monitor changes in parameters associated with operating the EMERGENCY GENERATORS (DIESEL/JET} controls including:
Al. 01 Al. 02 Al. 03 Al. 04 Al.OS Al.06 Al. 07 Al.08 Al.09 AZ.
A2. 01 A2.02 A2.03 A2. 04.
A2.05 A2.06 A2.07 A2.08 A2.09 A2.10 Lube o i 1 temperature *............*......*..*....**.....
Fuel c*onsumption rate...............*.......*....*.*..
Operating voltages, currents, and temperatures....**..
Crank case temperature and pressure........*.**..**...
Cylinder temperature different ia 1.....................
Emergency generator room temperature......**..*....*..
Gas generator temperature:
Plant-Specific..*....*....
Gas generator speed:
Plant-Specific..................
- Maintaining minimum load on emergency generator (to prevent reverse power).....***..**.*.*.**..*..***.....
Ability to (a) predict the impacts of the following on the E"ERGENCY GENERATORS (DIESEL/JET) ; and (b) based on those predictions. use procedures to correct
- control. or mitigate the consequences of those abnormal conditions or operations:
Parallel operation of emergency generator........**...
Unloading prior to securing emergency generator **..*.*
Operating unloaded, lightly loaded, and highly loaded~
Consequences of operating under/over excited.*.*.*....
S{nchronization of the emergency generator with other e ectrical supplies.**...*..**....**..**..***.....*...
Opening normal and/or alternate power to emergency bus Loss of off-site power during full-load testing.....*.
Initiation of emergency generator room fire protection system..*..*.*.......**...**..*..*....*..*.**.... * * * *
- Loss of A. C. power.....***.*.*.....*.*.**.*.. * *.***...*
LOCA *.**.**.*********.*.*********.*..*....**..********
Al.
Ability to monitor automatic operations of the EJtER6ENCY GENERATORS (DIESEL/JET) including:
A3.0l Automatic starting of compressor and emergency IMPORTANCE RO SRO 3.0*
3.0*
2.2*
2.3 2.8 2.9 2.6 2.7 2.4*
2.4*
2.3 2.4 2.0*
2.5 2.0*
2.5 3.0 '-:;. 3.1 3.5 3.6 3.1 3.1 3.4 3.4 2.9 3.0
' ~
3, 6 C;, 3, 6 3.4 3.4 3.5 3.7 3.3 3.7 3.7 4.1 3.9 4.2*
generator.............. *.............................*. 3.0 3.1 3.1 3.4 A3.02 A3.03 A3.04 A3.05 A3.06 Hin imum time for load pick up......................... 3.1 Indicating lights, meters, and recorders........*..**. 3.4 Operation of the governor control system on frequency and voltage control~********************************** 3.1 Load shedding and sequencing..*........*.....**....*.. 3.4 Cooling water system operation........................ 3.1 KIA catalog: BWR
- 3. 6-11 3.1 3.5 3.2
- .14
SYSTEM:
264000 Emergency Generators (Diesel/Jet)
Tasks as noted previously K/A NO.
A4.
A4. 01 A4.02 A4.03
- A4. 04 A4.05 A4.06 ABILITY Ability to manually operate and/or monitor in the control roOlll:
Adjustment of exciter voltage.. ~**********************
Synchroscope..........................................
Transfer of emergency control between manual and automatic............................................ ;
Manual start, loading, and stopping of emergency generator:
Plant-Specific..*...........**............
Tranifer ~f emergency generator (with load) to grid...
Droop setting...............*....*.............**...*.
SYSTEM GENERIC K/As
- 1. 'tKnowledge of operator responsibilities during* all modes of plant operation.
- 2. 'tKnowledge of system status criteri* which require the notification of plant personnel.
- 3. fKnowledge of which events related to system operation/status should be reported to outside agencies.
- 4.
Knowledge of system pu~pose and/or function.
- 5. fKnowledge of limiting conditions for operations and. safety limits.
- 6. fKnowledge of bases in technical specifications for limiting conditions for operations and safety limits.
- 7.
Knowledge of purpose and function of major system components and controls.
- 8.
Knowledge of the annunciator alarms and indications, and use of the response instructions.
- 9.
Ability to locate and operate components, including local controls.
- 10.
Ability to explain and apply all system limits and precautions.
- 11. 'tAbility to recognize indications for system operating parameters which are entry-level conditions for technical specifications.
K/A catalog: BWR 3.6-12 IMPORTANCE RO SRO 3.3 3.4 3.4 3.4 3.2 3.4 3.7 3.7 3.6 3.7 2.4*
- 2. 8*.
3.7 4.2 3.1 3.8 2.9 4.3*
3.6 3.8 3.4 4.1 2.9*
3.9 3.6 3.8 3.5 3.6 3.8 3.9 3.2 3.6 3.4 4.1
).
- 5. Which one of the following describes how long the class 1 E
- battery will have sufficient capacity to start a diesel generator after a blackout event?
- a. 30 minutes b, 60 minutes
- c. 90 minutes *
- d. 120 minutes Answer: c
% RATING:
.fr.
- 4.
While in MODE 4, Unit suffered a Prolonged Loss of Offsite and Onsite Power to All Three 4160 VAC ESF Susses. Which ONE of the following is the correct Emergency Classification?
- a. Site Area Emergency
- b. General Emergency
- c. Alert
- d. Notification of Unusual Event Answer: b
% RATING_
- 3. Selec.t the MINIMUM emergency event classification that involves failures of plant functions needed for protection of the public.
- a. Unusual Event
- b. Alert
- c. Site Area Emergency*
- d. General Emergency Answer: c
% RATING:
- 2. Following a loss of off-site power, a LOCA occurs on Unit (2).
Plant conditions are:
Reactor Water Level 1 70 inches, steady Average Drywell Temperature 250 F, rising Suppression Chamber Pressure 18 psig, rising Diesel Generators 3 and 4 loaded Group 10 isolated All Dryweli Coolers running Initiation of Drywell Sprays have been directed. How can the Drywell coolers be stopped per SEP-02?
- a. By placing all Drywell Cooler control switches on the RTGB to the OFF {L/0) position.
- b. By Pacing the PLACE D/W CLR A&D and B&C OVERRIDE Switches in XU-27 and XU-28.to the STOP position.
- c. QrW by placing the 480 VAC MCC breakers in the Reactor Building for all Drywell Coolers in OFF.
- d. OnJ.¥ by placing the Group 10 Valve control switches on the RTGB to the OVERRIDE/RESETposition, then to OPEN. -
Answer: b
% RATING:
ITEMS FOR DIFFICULTY RATINGS
- 1. Which one of the following reactor water levels will initiate the RHR pumps?
- a. Level 1 only
- b. Level 1 and 2 only
- c. Level 1 and 2 arid 3 only
- d. Level~ only Answer: a
% RATING:
_/
Angoff Method - Summary Percent of Item Difficulty Item 1 Item 2 Item 3 Item 4 Item 5 Rater 1 Rater 2 Rater 3 Rater 4 Rater 5 Average LOK 123
/
I Pract;cal Exerc;se On the attached record form and within your group individually rate the passing or cut score for each individual item that follows in this exercise.
Use the guidance stated in #2 above.
Then, convene briefly with your group, discuss your ratings, and make any changes needed to your rating. Finally, calculate your group's average for each item to yield an intended or anticipated individual item difficulty level. After that we will average the averages for the entire group.
Angoff Method The Angoff Method is one co11111only used method for setting a cut score for an examination.
The methodology relies on a panel of subject matter experts to estimate item difficulty.
The quality of the estimate or judgement is based upon the quality of the SHE experience with the population for which the examination is developed.
The Angoff method evaluates the examination after it is developed and assigns a cut score based upon its overall difficulty level. Unlike the NRC examination, whose cut score is established at 80 percent, the developer attempts to ~fit" the item to the cut score range.
In effect, the NRC uses a fixed cut-off which is a reverse process of the Angoff method.
The process works this way:
I. A panel of SHEs (typically three members) is established.
The panel members should have experience in the knowledge level and test performance with the population group for whom the test is intended.
rl ff.I,
Wl'-t'IM~
- 2.
Each member individually assigns a perc age st~tistic to each it m by asking the question:
What ercenta e of ndidates should be able to answer t~
question corre
?
eoret i ca n age s a 1 s 1.may range from o
00 percent.
In the matter of CRTs where testing is based upon training that should have occurred, the percent score should likely be in the higher ranges, i.e. >SO percent.
- 3. After the individual percentages are arrived at, the panel convenes to discuss and or modify any percentage changes. Then, the individual percentages are averaged to produce an aggregate level of difficulty for the item.
- 4.
The process is continued for each item. After all individual items are averaged, they are averaged a final time to arrive at an overall examination cut score.
Assumptions Assume individual rating scores should not vary widely for internal reliability.
Assumes that the candidates have been trained.
Assumes that SHEs know the job and its expectations, have a grasp of the training program content and coverage of the knowledge asked in the question, and most importantly, have an understanding of how candidates have performed in the past on either an identical or similarly phrased question.
CUT SCORE APPROACHES
- George M. Usova USNRC FIXED
- Set at a predetermined level by policy prior to development.
- Level of difficulty is set prior to and during the design and development t~ "fit" within a cut score range, e.g., 70-90.
- VARIABLE
- Level of difficulty estimated by panel at the item* and overall test level llftlr the item is developed.
Both approaches are estimations and require either the developer or
. rater to have knowledge of...
- the job for which the test is developed
- candidate level of knowledge
- candidate past performance on similar items
- the training program scope arid depth
- test item content knowledge
- 1.
Examine the item for unnecessarily difficult wording and simplify it.
- 2.
Identify those misleads which are likely to be most attractive to better applicants and substitute misleads which will be less attractive to this group.
- 3.
Try. splitting the item into two items if it is measuring two concepts or processes.
If the item is too easy, substitute misleads which have an element of truth but are defensibly
- wrong.
-r
- 1.
Content. The reviewer needs to check that the content is relevant to the job, both the concept and the level of the concept, and that it is content which is required before entry to employment. It should not measure job knowledge that is normally expected to be learned on the job. The reviewer should make certain that
- there is one and only one correct answer to each question. Since all item writers presumably have working or supervisory experience with the job, they should as a general rule be able to answer any item required for selection on the examination. If more than one writer has trouble with a given item, it is well to examine it carefully for appropriateness. However, a level of knowledge beyond that required for job performance may be required to spot errors in assumptions or points which are open to. disagreement among experts. Therefore, items covering specialized content which have been written by a specialist should be referred for review to at least one other specialist. If no one else has this specialist background, these items must be submitted to specialists outside the training program.
- 2.
Difficulty level. Each reviewer should be asked to make two estimates of difficulty:
- a. The percent of those on the job(s) for which the test is designed who could answer the question and
- b. The percent of the candidate population who could answer it.
Estimates of difficulty made by reviewers may vary somewhat but should not vary widely.
Unless there is some reason to doubt the estimates of some reviewers, the average estimate may be taken as a basis for judging the suitability of item difficulty for the pretest. (Items should be revised if estimates fall well below or above the 70 - 90 target range.)
- 3.
Measurement principles. The reviewers will need to review the item relative to the list of Item Writing Rules. This list appears to be long, but with practice, the concepts become internalized, and there should be less time for this review.
- 4.
Editorial review. This review will ordinarily be done only after the item is considered in final pretest form. It should be done by someone with competence in English usage and expression. The item writers may have such a background and be qualified. If not, the training department should enlist the services of another person who can do this review. There are some advantages in having the item reviewed for this purpose by someone not familiar with the area being tested. Such a person can check not only the clarity, grammar, expression, spelling and punctuation, but can determine whether the item is answerable by a person without knowledge of the field.
It facilitates catching errors for the editor to read through the test once for each of the following: clarity and expression, grammar, spelling, and punctuation.
Item Revision If item difficulties appear to be running too high (i.e., low percent pass estimates) the following revision techniques may help:
Research has shown that when a person is writing items in his own area of specialization, there is a tendency to underestimate the difficulty of a concept or principle he is testing; this tendency can manifest itself in two ways: (1) he will view items of average difficulty as easy or (2) in an effort to get plausible misleads, for example, among distractors in a multiple choice test item, he may make the item even more difficult. For this reason, an estimate of item difficulty made by a few reviewers will probably be more accurate than one made by the author of the item.
Assumptions The dynamics between stem (content and operational validity) and distractor coupled with psychometric adherence plays a fundamental role in assessing LOO (discriminant validity).
Assessing item difficulty is an estimate. Actual post-exam performance confirms or disconfirms the estimate. Exam writers should review actual post exam performance to determine item difficulty and conduct a distractor analysis, i.e., which distractors distracted and which did not.
Item Review Reviewers can assist by evaluating item writing in progress; reviews can take the form of technical, editorial, and psychometric checks. An editorial review, for example, woulci check whether there is unnecessary wordiness and might find an item to appear overly leng~hy or the writer is devising too complicated a problem situation. In the latter case, the reviewer"can question whether the item writer is attempting to test more than one concept or process and, if so, whether these can be tested with separate items; in this case, the editorial review overlaps into a technical review.
Dlstractors On the average, Item difficulty should be moderate, in the 85-90 range. Under this premise, there !;hould be a reasonable expectation that some candidates may miss t!:le answer.
Distractors should distract to some extent; otherwise they do not meet their Tntended purpose.
If they do not distract, seek ways to make them distractible..
I* ~*
One key question that the exam writer/reviewer should ask for~ distractor is the following:
Could some percentage of the test group choose that distractor?
- If the answer is yes, then the distractor is adequate. if the answer is no, the distractor may contribute toward making the item too easy. Revise the distractor and substitute misleads which have an element of truth but are defensibly wrong.
The major areas item writers should concentrate their review ')n are shown below. There is an advantage in considering each of these four areas separately and in this order. If there is a need to revise an item on the basis of one stage of the review, the changes can be agreed upon before going further. The changes at each stage could well affect those reviews which follow. For example, a criticism which appears to affect only one option may lead to changes in other parts of the item and time spent reviewing the item for grammar and punctuation may be wasted.
- ,1
ESTABLISHING A SYSTEM FOR EXAM DEVELOPMENT Writer Qualifications The level of test writer/reviewer professionalism (training and experience) are central underpinnings toward development of a successful examination product. Utility test writers will write test items that measure candidates' possession of knowledge and skills and will likely review items written by others. They will also revise the items. as necessary, on the basis of peer or NRC reviews prior to administration.
Good item writing involves skill and art. To enhance the probability of success, item writers should have, as a minimum, the following qualifications:
I.
Experience in the job for which the test is being designed or in supervising it.
- 2.
Strong knowledge of relevant content areas for which items are being* developed.
The knowledge of the specialist must be substantially beyond that required to answer the test questions in his specialty area.
- 3.
An understanding of fundamentals of psychometric principles or the accepted guidelines for writing good test items.
- 4.
Interest in the examination project with motivation toward the item writing task.
, 5.
Ability to work in a group and openness to suggestions regarding his work.
- 6.
Willingness to persevere with a task and try a variety of alternatives approaches.
Selection of those persons with the most aptitude for and interest in writing items can save considerable item writing time. There should be "representation of the relevant specialty areas.
to provide the needed coverage." Additionally, such persons need to be familiar with the level of development, training and experience of the candidate population for which they are developing examinations. Specifically, the item writer must know the RO/SRO job and its relevant safety-significant knowledge and abilities from which test items, JPMs, and scenario sets will be developed.
Stability. Keep the examination development team trained and consistent.
Achieving Appropriate Item Difficulty As is discussed in conceptual detail in Appendix A, both level of knowledge and item difficulty are at the heart of examination discrimination. Test writers should develop items that are estimated to center around the 80 percent cut score level. Pragmatically, this means that individual item difficulty should be estimated to fall in the 70 - 90 percent difficulty range. These parameter should not be viewed as precise benchmarks, but rather as approximate end points.
If post examination analysis confirms that actual item difficulty is either greater or lower than the estimated item difficulty, then item writers should adjust.their frame of reference accordingly and aim at a somewhat higher or lower levels in developing like-kind items for the next examination.
TEST EVALUATION:
ITEM ANALYSIS
- 1.
ITEH DIFFICULTY (PASS RATE):
2
- WAS THE ITEM TOO DIFFICULT OR TOO EASY?
- ITEM DISCRIMINATION:
DID THE ITEM FUNCTION AS INTENDED?
DID HIGH PERFORMERS DO WELL ON THE ITEM, AND POOR PERFORMERS DO POORLY?
-~..
- 3.
FOR MULTIPLE CHOICE ONLY:
j~,.
WERE EACH* OF THE MULTIPLE-CHOICE DISTRACTORS EFFECTIVE?
l:.
t
~
~
- nt
ITEM ANALYSIS RESULTS Total Possible Points: 100 Number of Test Takers:
49 Mean Score:
79%
Highest Score:
94%
Lowest Score:
56%
Item Discrimination
. Item Ratio Correl.
Res~onse Freguencies Item Difficult~
No.
{Pass Rate)
Top 1/3 Lower 1/3.
A B
c D
E 1
92%
100%
85%
0.20 2
2 45*
0 0
2 98 100 92 0.22 0
1 48*
0 0
3 90 92 77 0.18 3
2 0
44*
0 4
98 100 100
-0.01 48*
1 0
0 0
5 90
. 100.
69 0.44 44*
0 4
1 0
6 98 100 92 0.22 0
48*
0 1
0 7
49 54 54 0.11 0
24* 23 2
0 8
94 100 85 0.20 0
46*
0 2
0 9
98 100 100 0.06 0
0 1
48*
0 10 27 46 8
0.35 6
3 13* 19 8
11 61 100.
31 0.47 30* 19 0
0 0
12 100 100 100 o.oo 0
49*
0 0
0 13 65 92 46 0.40 4
10 2
32*
1
- 14 90 100 77 0.24 44*
2 2
1 0
15 22 0
15
-0.03 12*
5 11 18 4
16 86 100 62 0.39 1
0 42*
2 4
17 100 100 100 o.oo 0
49*
0 0
0 18 94 100 85 0.29 2
46*
0 0
0 19 94 100 77 0.45 1. 46*
2 0
0 20 88 92 69 0.25 4
43*
0 2
0 21 86 92 62 0.31 0. 6 42*
1 0
22 96 100 85 0.20 1
0 0
1 47*
23 92 100 85 0.29 0
0 2
45*
2 24 2
0 8
-0.25 6
42 0
1*
0 25 73 85 62 0.21 10 36*
1 2
0 26 41 85 38 0.30 24 20*
5 0
0 27 80 100 62 0.39 39* 10 0
0 0
28 92 100 92 0.15 1
45*
0 3
0 29 98 100 92 0.22 48*
1 0
0 0
30 96 100 92 0.11 1
47*
1 0
0
ADDITIONAL GUIDANCE MULTIPLE-CHOICE ITEMS
.17.
Not a collect;on of unrelated true-false statements
- 18. All necessary/poss;ble ;nfonnat;on prov;ded in stem
- 19. Positively stated stem, or intent is to test what not to do
- 20. Free of double negatives
- 21. All answers equally relevant and important
- 22.
- None of the Above* and *All of the Above*
avoided
- 23.
Answers are free of "specific detenniners 11 (clues)
- 24. Distractors based on corrmon misconceptions
- 25.
Answer options ordered sequenti~lly Poor. Marg;nal Good
- f.
. "L;
ITEM REVIEW CHECKLIST fil ITEMS
- 1.
Adequacy of testing objective
- 2.
Match between item, testing objective, and K/A
- 3.
Importance of item: relationship between being able.to answer the question and job competence
- 4.
Clear, concise, easy to read S.
All necessary information and assumptions contained in question
- 6.
Appropriate level of. knowledge (memory, comprehension, analysis/synthesis)
- 7.
Free of unnecessary difficulties, irrelevancies
- backward logic*
- 8.
Covers one concept or topic
- 9.
Face validity of question -- exolicit operational basis
- 10. Important words that could be overlooked or misread are highlighted (underlined, capitalized, bold)
- 11.
No unintentional clues as to correct answer
\\
- 12. Appropriate for written test and selected question format (e.g., short answer:
multiple-choice)
- 13. Match between item and answer key
- 14. Only one correct answer
- 15. length and scope of answer key appropriate
- 16. Point values specified on question and answer key 1
~
Marginal Good -
- RO QUESTION #021 While performing actions in E-3, "Steam Generator Tube Rupture" the Control Room Supervisor asks the Balance of Plant Operator to check intact Steam Generator narrow range levels greater than 4% Which ONE of the following BOP responses would satisfy XXXX Plant Communication Guidelines?
A. Yes, intact Steam Generator narrow range levels are greater than 4%.
B. Yes, intact Steam Generator narrow range levels are:'50%
and stable.
C. Yes, intact Steam Generator narrow range levels are
- increasing.
D. Yes, intact Steam Generator narrow range levels are ::10°/o ANSWER:
B.
RO#B SRO#?
KIA #194001A105 OBJECTIVE #003A060H
REFERENCES:
UEND-COMMUNICATIONS-01, Page 4 of 5
,I
.! ~11
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,r*I
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~ -~
SRO QUESTION #044 Which ONE of the following events is required to be recorded in the RO Narrative Logs?
A. Chemical addition to the condensate system.
B. Security Event due to Security System (SAS) malfunction.
C. Annunciator switchyard carrier potential/tone loss,*
alarms.
D. Unexpected ESFAS alarm on ESW system.
ANSWER:
D.
R0#9 SR0#8 KJA #194001A106 OBJECTIVE #003A0281 REFERENCES> ODP-ZZ-00006, Section 4.3
SRO QUESTION #046 Which ONE of the following is the preferred method of injecting highly borated water into the RCS during an ATWS?
A. Manually align Charging Pump suction to the RWST.
B. Borate through BGV0177, Alternate Immediate Bo ration Valve.
C. Manually initiate a Safety Injection from RL001.
D. Borate through BG-HV-8104, Emergency Borate to Charging Pumps Suction Valve.
ANSWER:
D.
SR0#80 KJA #000029G11 OBJECTIVE #0030290B
REFERENCES:
FR-S.1
Question 16:
Which one of the following statements is correct concerning an uncoupled control rod during coupling cheeks?
- a. Up to two attempts may be made to recouple the drive.
- b. ff attempts to recouple the rod are unsuccessful, the rod should be disarmed at that position.
- c. Digital display of control rod position on the Rod Display Module will go blank if the rod is uncoupled.
- d. When the ROD UNCOUPLED indicating light has illuminated, it will not clear until the rod is successfully recoupfed.
Answer
- c.
References:
Off-Normal Instruction (ONl)-C11-2, "Uncoupled Control Rod (Unit 1 )"
SRO QUESTION #032 Which of the following is NOT an event the MSIVs are used to protect against?
A. Steam Line Break inside Containment B. Feedwater Line Break upstream of check valve C. Steam Line Break outside Containment D. Steam Generator Tube Rupture ANSWER:
B. Feedwater Line Break upstream of check valve KIA #03501 OK601 OBJECTIVE #0110200A REFERENCE T61.0110.6 LP-#20