ML19354E020

LER 89-016-01:on 890913,generator 1B Power Circuit Breaker Opened,Causing Unit Runback to 54% Power & Failure of Generator Breaker Air Pressure Gauge.Caused by Equipment Failure.Pneumatic Gauge replaced.W/900117 Ltr

ML19354E020
Person / Time
Site:	Catawba
Issue date:	01/18/1990
From:	Glover R, Owen T DUKE POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
LER-89-016-02, LER-89-16-2, NUDOCS 9001250233
Download: ML19354E020 (9)

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Dukihunt Company *

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. 'Catauha NuclearStati n'-

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' Clover, S C 29710 DUKEPOWER

' January' 17, 1990

'D'ocument' Control Desk-

.U. S. Nuclear Regulatory Commission Washington, D.-C.c -20555-

Subject:

> CatawbaLNuclear.Stati'on Docket No. 50-4131 .

.LER'413/89-16, Rev. 1 Gentlemen:

Attached is-Licensee Event Report 413/8D-16,' Revision?1,- concerning TECHNICAL SPECIFICATION.3'O.3 ENTERED DUE'.TO FOUR~ CHANNELS OF POWER.

RANGE' INSTRUMENTATION BEING DECLARED INOPERABLE:FOLLOWING UNIT' RUNBACK.

AS.A RESULT 0F FAILURE.OF,A GENERATOR' BREAKER AIR PRESSURE GAUGE..

This event was considered to beTof no significance lwith respect'to the, health and' safety of the,public.

Very truly.yours,

[

Tony ." Owen.

Station Manager 1 keb\LER-NRC.TBO xc: Mr.-S.'D. Ebneter American^ Nuclear. Insurers Regional Administrator,-Region II' _c/o Dottie.Sherman,'ANI. Library l U. S.1 Nuclear Regulator Commission The Exchange, Suite ~245 101LMarietta Street, NW, Suite 2900- -270 Farmington~Avenuel Atlanta. GA -30323 Farmington, OT 06032 M &'M Nuclear. Consultants Mr. K. Jabbour 1221 Avenues of tho' Americas U'. S. Nuclear' Regulatory Commission-Nek York, NY 10020 Office of Nuclear Reactor'. Regulation .J Washingtoni D. C. L205S5 .; i

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• ' ' ' * ' Four Channels of Power Range Instrumentation' Inoperable Following Unit-Runback As A Result of Failure of a Cencrator Breaker Air Pressure Gauge EVENT OATI 161 LER NUMeER 18) REPORT DATE (7) OTHER F ACitfTIES INVOLVED fel MONT'ef%AY YEAR YEAR -

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On September 13, 1989, at 0541' hours Unit i was in Mode 1, 100% Power Operation. Generator 1B Power Circuit Breaker (PCB) opened causing Unit runback to 54% Power. Four out of four channels of Power Range Nuclear Instrumentation  !'

(PRNI) displayed greater than the 5% allowable mismatch between Rated Thermal l l

Power (RTP) and Nuclear Power, in the non-conservative direction. At 0550-hours, l Technical Specification 3.0.3 was entered and Work Request 4099 SWR was issued-l to complete calibration of the PRNIs. The Unit was stable at 54% Power at 0630 '

hours and the calibrations were performed. Following the required calibrations of the PRNIs, the Unit exited Technical Specification 3.0.3. The pneumatic gauge was subsequently replaced, and Generator PCB 1B was restored.to service.

Unit Power increases commenced at 1003 hours0.0116 days <br />0.279 hours <br />0.00166 weeks <br />3.816415e-4 months <br />'on September 13, 1939. All required PRNI calibrations were completed to within 2% of RTP by 1525 hours0.0177 days <br />0.424 hours <br />0.00252 weeks <br />5.802625e-4 months <br />.

Unit Power reached 97% Power at 1815 hours0.021 days <br />0.504 hours <br />0.003 weeks <br />6.906075e-4 months <br />. At 2100 hours0.0243 days <br />0.583 hours <br />0.00347 weeks <br />7.9905e-4 months <br />, Unit Reactor Power reached 100%. The Power Range mismatch was considered to be an expected phenomenon following e Unit runback. This incident has been attributed to Equipment Failure due to the failure of the pressure gauge on the PCB which caused the Unit runback.

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j ~ The purpose of the Out of Core Instrumentation [EIIS:JG] (ENB) System is to 4 s monitor. Reactor-[EIIS:VSL] Core leakage neutron flux and generate appropriate t

< trips and alarms for various phases of. Reactor [EIIS:VSL], operations. The three i 2 ' separate overlappi.ng ranges' of Source Range, Intermediate Range, and Power Range

, also provide control functions and indicate Reactor status during Mode 2,

Startup and Mode 1, Power Operation _ Technical Specification;4.3.1.1 requires . S that channel calibration ~be performed daily on;the Power Range Neutron Flux High Setpoint. This is to be. performed by-comparison-of. calorimetric (reactor . .

, thermal power best estimate, based on; actual plant indicator temperatures). to ,

) excore' power (based upon nuclear'powernlevels from detector instrumentation) i indication when the Unit is above 15% Rated Thermal Power.(RTP). Excore channel  !

' gains are to be adjusted to make indicated.excore power consistent with

? indicated calorimetric power whenever- this comparison . reveals an absolute  !'

j difference of more than 2% between the two..

l' Technical Specification 3.3.1, Table 3.3-1, requires-that three out of 1our-channels of PRNI must be operable during. Modes 1 and 2.  ;

During power operation, a power.. range channel must be considered INOPERABLE i 1 whenever a mismatch exists-between calorimetric; power and~excore power- >i indication that is-greater than 5.0% in the non-conservative direction '

'(calorimetric power greater'than:excore power). If the mismatch is between 2.0%

L and'5.0% in the'non-conservative direction, the channel is OPERABLE as long as i

. the calibration process has been ' initiated. ;When the Unit is engaged in a= power maneuver which results in a mismatch between . calorimetric and excore power in 1 excess of 2%, 'excore adjustment may be delayed.until the Unit reaches a steady state power level, provided the mismatch does not exceed 5.0% in the non-conservative direction, as specified by the Technical; Specification

' Interpretation, dated June 2,'1989.

Technical Specification 3.0.3 is required to be entered when the Unit.is -

operating in a condition prohibited by Technical Specifications. This condition .

exists when a Limiting Condition for Operation-is not met except as provided in the associated Action Requirements. It requires'that within one hour-action- -

shall be initiated to place the Unit in a Mode-in which the' specification d m s {

not apply by placing:it, as applicable, in:

a. At least HOT STANDBY within'the next 6_ hours,

b. At least HOT SHUTDOWN-within the following 6 hours6.944444e-5 days <br />0.00167 hours <br />9.920635e-6 weeks <br />2.283e-6 months <br />, and

c. At least COLD SHUTDOWN within'the subsequent 24' hours.

The Unit Main Power [EIIS:EA]-(EPA)' System's primary function is to generate and transmit power '.o Duke's Transmission. System while-simultaneously supplying the -

6.9KV Normal' Auxiliary Power-[EIIS:EA]-(EPB) System. 'If the generator NK Om 366A - .g.s. cro, 19tg.90439 00010 W__-. - . . _ --_ - . . - . . . . . - ..

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[EIIS: GEN]-is out of service, the EPA System is used to supply power from the

~

e Transmission System to the Unit Auxiliary Power System. The EPA ~ System is 5 divided into non-safety trains, connected to the 230KV switchyard through a  ;

h step-up transformer [EIIS:XFMR] and two power circuit breakers [EIIS:BRK] (PCBs) 1 K located in the switchyard. A generator breaker is provided on each train. The l- generator breaker and step-up transformer combination on each train is capable of carrying approximately fifty percent (750MVA) of the rated generator output.

EVENT DESCRIPTION On September 13, 1989, at 0541 hours0.00626 days <br />0.15 hours <br />8.945106e-4 weeks <br />2.058505e-4 months <br />,'with Unit 1 at 100% Power Operation, i Generator PCB 1B tripped open, causing an unexpected Unit runback. Operations Q entered AP/0/A/5500/03, Load Rejection. At 0550 hours0.00637 days <br />0.153 hours <br />9.093915e-4 weeks <br />2.09275e-4 months <br />, the PRNI:versus Thermal' f Power (TP) was observed to be greater than 5% non-conservative on all four

(- channels. Technical Specification 3.0.3 was entered'at 0550 hours0.00637 days <br />0.153 hours <br />9.093915e-4 weeks <br />2.09275e-4 months <br />, and Work . 'i Request 4009 SWR was issued to direct the Instrumentaion and Electrical (IAE) section to calibrate the PRNI. The-determination was made at 0600 hours0.00694 days <br />0.167 hours <br />9.920635e-4 weeks <br />2.283e-4 months <br />,'that Generator PCB 1B tripped on low air pressure as a result of a failed pressure gauge at the PCB, Phase X. The Unit was stablized'at 54% Power at'0630' hours.

The Control Room Operator (CRO) exited Technical Specification 3.0.3 at 0640  ;

g hours, due to the acceptable power mismatch on three of the four channels. '

Operations determined-that the failed pressure gauge would be replaced by 0930 hours0.0108 days <br />0.258 hours <br />0.00154 weeks <br />3.53865e-4 months <br />, by the Transmission Department; therefore, adjustment of the remaining.

power range channel per Technical Specifications was unnecessary as power escalation was expected to correct the mismatch problem. ,

' Generator PCB 1B was restored to service at 0952 hours0.011 days <br />0.264 hours <br />0.00157 weeks <br />3.62236e-4 months <br />, following the -

i replacement of the pneumatic pressure gauge. No problems were encountered following this action.

At 1003 hours0.0116 days <br />0.279 hours <br />0.00166 weeks <br />3.816415e-4 months <br /> on September 13, 1989, Unit 1 Power increase began to establish '

100% Power Operation. Power was increased from 54% at a rate.of 10% per hour.

At 1340 hours0.0155 days <br />0.372 hours <br />0.00222 weeks <br />5.0987e-4 months <br />, Reactor power was at 90% and holding to perform Main Steam

[EIIS:SB] (SM) System control valve _[EIIS:V] movement tests and to complete final PRNI calibrations. All four channels of the PRNI registered Quadrant ,

Power Tilt Ratios of less than 1.02%. The control valve movement test and PRNI 1 calibrations were complete at 1525 hours0.0177 days <br />0.424 hours <br />0.00252 weeks <br />5.802625e-4 months <br />. Power _ increases continued to 100% at '

3% per hour. Unit power reached 97% thermal power at 1815 hours0.021 days <br />0.504 hours <br />0.003 weeks <br />6.906075e-4 months <br /> and by 2100 hours0.0243 days <br />0.583 hours <br />0.00347 weeks <br />7.9905e-4 months <br />, the Unit reached 100% Power Operation.

CONCLUSION This incident has'been attributed to Equipment Failure. The pneumatic gauge, manufactured by Protais (France), normally displays _a pressure of 500 lbf/sq.in.  !

on Phase X, Y, and Z of the Generator B PCB. The failure of the gauge occurred '

at the connection of the bourdon tube and the linkage of the meter. The pneumatic pressure that resulted from the break of the soldered connection caused the gauge to be separated from its housing on the breaker. The immediate l

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TEXT ta mese guess e segueset use estseenaf WC Fen m W 117l drop in pressure caused the Generator 1B PCB to tr'ip open. During the fourteen  !

year use history of the Protais. gauges, there have.been no failures reported.

The mismatches reported.on the PRNI channels after Unit power reduction were considered to be-an expected phenonmenon. Within the past twelve months, one previous Problem Investigation Report (PIR)-2-C88-0335 was-initiated as a. result

' of entering Tech Spec 3.0.3 due to all four channels of PRNI being declared

-inoperable. This occurred during a power manuever of Unit 2 from 96% to 51%

' power. All channels were' inoperable due to the allowable non-conservative mismatch between calorimetric power and excore power. The cause of that incident was attributed,to Defective Procedures. The procedure OP/2/A/6100/03,. -

Controlling Procedure'For Power Operation,.did not contain a Caution or other L information concerning the Power Range mismatch that normally occurs on a power

( decrease. The procedures-for both Units were revised. A Technical .

F Specification Interpretation revision was issued June 9, 1989. Since this previous incident was not. caused by Equipment Failure,- the current incident is not considered to be a recurring event.  ;

The Protais' gauge is not NPRDS reportable.

CORRECTIVE ACTION l

l SUBSEQUENT t

l 1) Work Request 4099 SWR was issued to recalibrate the PRNI.

l l 2) The Protais pneumatic gauge was replaced for? Generator IB PCB.  !

! 3) Recalibration of PRNI was completed, per IP/1/A/3240/11.

4) Safety Analysis was revised based upon review.

5) The' failed Protais pneumatic gauge was sent to the Duke Power i Standards Laboratory for' failure analysis and testing.

L SAFETY ANALYSIS l

The excore power range neutron detectors [EIIS:XT]'are arranged and located such that one detector measures core leakage neutron flux for one quadrant. Each l

detector and its associated circuitry comprise one channel, for a total of four PRNI channels. The Power Range High Neutron Flux Trip (High Setpoint) function utilizes a 2-out-of-4 trip logic. l Nn po7su sse.

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', 1 Catawba Technical Specification 4.3.1.1 requires that channel calibration be-performed daily on the Power Range Neutron Flux High Setpoint. This is to be performed by comparison of calorimetric (thermal.best estimate) to excore. power

..1 indication when the Unit is above 15% rated thermal power-(RTP). Excore. channel

[; gains are to be adjusted to make' indicated excore (NIS) power consistent with .

' indicated calorimetric power whenever this comparison reveals an absolute difference of more than 2% between the two.

During power operation, a power range channel must be considered IN0PERABLE

~

whenever a mismatch exists between calorimetric power and excore power -

. indication that is greater than 5.0% in the non-conservative direction i (calorimetric power greater than excore power). If_the mismatch is between 2.0%

f.I '

and 5.0% in the non-conservative direction, the channel is OPERABLE as long as the calibration process has been initiated. When the-Unit is engaged inLa power-maneuver which results in a mismatch between calorimetric and excore power in excess of 2%, excore adjustment may be delayed until-the Unit reaches,a steady: l state power level, provided the mismatch does not exceed 5.0% in- the non- i' conservative direction, as specified by the Technical Specification Interpretation, dated June 2, 1989. The justification for the increased allowable mismatch is based upon the existing margins in the Steam Generator

,, [EIIS:HX] (S/G) low-low level and power range high flux (high and low) setpoint  !

i calculations, power range response during specific transient analyses, and the- i conservatisms inherent in the Catawba FSAR analyses.

Bank D Rod Cluster Control Assemblies (RCCAs) are located in the core such that- j one RCCA is inserted in the middle of the core along.the vertical axis, with one '

'RCCA inserted in each of the four quadrants (for a total of 5 RCCAs in Control Bank D). -The RCCAs in control Bank D are positioned more closely to the excore neutron flux seen by these detectors to a greater degres than the other control banks. This phenomenon commonly _ occurs during power reductions in which Control Bank D is partially inserted.

~

Core quadrant 1 (channel N43) mismatch exceeded 5% from 0555 hours0.00642 days <br />0.154 hours <br />9.176587e-4 weeks <br />2.111775e-4 months <br /> to.0643 hours0.00744 days <br />0.179 hours <br />0.00106 weeks <br />2.446615e-4 months <br />; core quadrant 2 (channel N42) mismatch exceeded 5%'from 0555 hours0.00642 days <br />0.154 hours <br />9.176587e-4 weeks <br />2.111775e-4 months <br /> to 0630 hours0.00729 days <br />0.175 hours <br />0.00104 weeks <br />2.39715e-4 months <br />; core quadrant 3 (channel N44) mismatch exceeded 5% from 0555 hours0.00642 days <br />0.154 hours <br />9.176587e-4 weeks <br />2.111775e-4 months <br /> s to 0640 hours0.00741 days <br />0.178 hours <br />0.00106 weeks <br />2.4352e-4 months <br />; core quadrant 4-(channel N41) mismatch exceeded 5% from 0552 hours0.00639 days <br />0.153 hours <br />9.126984e-4 weeks <br />2.10036e-4 months <br /> to 0623 hours0.00721 days <br />0.173 hours <br />0.00103 weeks <br />2.370515e-4 months <br />. Therefore, all four NIS channels were technically inoperable from 0555 hours0.00642 days <br />0.154 hours <br />9.176587e-4 weeks <br />2.111775e-4 months <br /> to 0623 hours0.00721 days <br />0.173 hours <br />0.00103 weeks <br />2.370515e-4 months <br />, a total of 28 minutes. The maximum mismatch errors were 8.1%, 7.8%, 6.95%, and 8.2% for quadrants 1, 2, 3, and 4, respectively. During this short period of multiple channel inoperability, the channels were not functionally inoperable, as they would have still_provided input to the SSPS Reactor trip function. The NIS channels were only 3.1%, 2.8%, j 1.95%, and 3.2% non-conservative beyond.the allowable mismatch, for quadrants 1  !

through-4, respectively, i

-The following'is a list of Catawba FSAR Chapter 15 transients in which credit is assumed for the Power Range High Neutron Flux Trip (High Setpoint):

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t j 1)- Startup of an-Inacti.ve Reactor Coolant Pump [E!IS:P] at an Incorrect  !

1 Temperature (discussed in Section 15.4.4).

S- .

1

2) Feedwater System Malfunctions that Result in a Reduction in Feedwater b Temperature (discussed in Section 15.1.1).

b L 3) . Excessive Increase in Secondary Steam Flow (discussed in Section. <

[.. -15.1.3).

4) Inadvertent Opening of a Steam _ Generator Relief or Safety Valve '

(discussed in Section'15.1.4).

f I

j 5) Steam System. Piping Failure (discussed in Sectionf15.1.5). .

ls ll 6) Uncontrolled Rod [EIIS: ROD] Cluster Control Assembly Bank Withdrawal

[; From a Suberitical or Low Power Startup. Condition (discussed in L Section 15.4.1), r

( .

[ 7) Uncontroll'ed Rod Cluster Control Assembly Bank Withdrawal.at Power p (discussed in Section'15.4.2).

h

8) . Spectrum of Rod Cluster Control Assembly Ejection- Accidents (discussed in Section 15.4.8).

The following discussion outlines the protective features'which existed for the above scenarios other than the Power Range High Neutron Flux Trip Function (High Setpoint): -

1) The "Startup of an Inactive Reactor' Coolant Pump at an Incorrect Temperature" scenario.is not applicable. All.four Reactor Coolant loops were in operation during this incident. However .if the Unit-had been operating in'a three loop configuration, any. postulated power excursion would have been terminated.at the P-8 setpoint (2-out-of-4 '

power range indications > 49% full. power).

L 2) The Unit would be protected against a "Feedwater System Malfunctions that Result in a Reduction in Feedwater Temperatures "' scenario by the Overtemperature and Overpower Delta-T trip functions.

3) The Unit would be protected against the " Excessive Increase-in Secondary Steam Flow" scenario by the Overtemperature and Overpower-Delta-T trip functions. -;

L

' 4) The Unit would be protected against the " Inadvertent Opening of a- ,

Steam Generator Relief or Safety Valve" scenario.by initiation of a Safety Injection signal (due to steamline pressure) which initiates a' .

Reactor Trip signal. The~0vertemperature and Overpower Delta-T trip functions also provide Reactor protection in this scenario. j g,o= x.. . ..... cro i,.. 3m s., m m .

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d 5) The Unit would be protected against a " Steam System Piping Failure"-

J' scenario by initiation of a Safety Injection signal (due to steamline>

e' pressure) which initiates a Reactor Trip signal. The Overtemperature

[ and Overpower Delta-T trip functions also provide Reactor' protection =

D' in this scenario.

? 6) The " Uncontrolled Rod Cluster Control Assembly. Bank Withdrawal From a i Subcritical-~or. Low Power.Startup Condition" scenario,is not 2 applicable, as this. incident involved a load: follow power reduction:

~

(Unit runback). ,

1 7) The " Uncontrolled. Rod: Cluster: Control- Assembly Withdrawal at Power"~

i scenario is. assumed to be terminated by the following trip functions r^

in addition to the Power Range High Neutron Flux Trip Function (High:

• Setpoint): . 0vertemperature and'0verpower Delta-T, pressurizer

. pressure, and pressurizer level. In, addition to these trip functions, .

there are the following RCCA withdrawal blocks: '

[ a) high-neutron flux, b) Overtemperature Delta-T, and F c) Overpower Delta-T. For slow RCCA withdrawal accidents, i thermal-time constraints on the heatup do not become'al factor; the Unit is tripped and DNBR-is maintained above the limit.value. ' <

E

8) The " Spectrum of Rod Cluster Control Assembly Ejection Accidents" b scenario assumes credit for the High Neutron: Flux Rate. Trip Function.

! Furthermore, in any postulated rod withdrawal accident, the out-of-calibration L condition would have corrected itself during the transient-due to the absence of 1 the cause of the deviation, i.e., insertion of Control Bank D.~ Also, the I conservative effects of moderator and doppler feedback would tend to limit any

~

postulated power excursion.

The calibration problem was one of gain setting, or overall absolute value power indication. The ability of the NIS to detect axial flux difference (AFD) and- i high flux rate was unaffected. The Overtemperature Delta-T and the Overpower Delta-T Trip Function receives AFD as an input _to the setpoint equation, and the Overpower Delta-T Tr.ip Function is unaffected by neutron flux, .Therefore, the-high flux rate, Overtemperature Delta-T, and Overpower Delta-T Trip Functions ' -  ;

remained intact and functional ~throughout this event. -The Overtempe'rature ,

Delta-T Trip function protects against DNB conditions, and the Overpower Delta-T I Trip Function ensures that allowable heat generation rate-(kw/ft)=is not

. exceeded.

The Unit 1 0-3 S/Gs utilize a ramped operating level based on NIS indication input to the feedwater control valve position. ~Hence, during this transient, it -1 is likely that the control system was " searching", causing oscillations in-ge *om un .u. . era, n,... w .,. m w a m .

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l Catawba Nuclear Station, Unit 1 o l5 l0 jo l0 l 91l3 8l 9 -

0j 1 l6 0 l1 0l8 or 0 l8 1 itxt w- . = wme w asuu nn j feedwater flow and S/G level. For example, at the minimum achieved power level )

of 54% RTP (thermal best estimate), the feedwater control valves would have been-L throttling to maintain approximately 48% power based on NIS input. However, these oscillations were apparently minor, as S/G low-low level Reactor trip and. j 7

high-high level signals-did not occur.-

l .

\ .

F Addition' ally, power mismatch signal, based on the difference between Turbine I impulse pressure (correlative thermal power level) and NIS indication, is a control input to the Rod Control System program. However, this program does not utilize absolute power mismatch, but rather, rate of change of power. mismatch  ;

(i.e., it is an anticipatory function). Therefore, the out-of-calibration-

- i condition of the NIS did not affect automatic rod control. j After recovery of the NIS from the out-of-calibration condition, core quadrant 2 1 Quadrant Power Tilt Ratio (QPTR) exceeded the value (1.02) allowed by Technical_

l Specifications (from 0800 hours0.00926 days <br />0.222 hours <br />0.00132 weeks <br />3.044e-4 months <br /> to 1150 hours0.0133 days <br />0.319 hours <br />0.0019 weeks <br />4.37575e-4 months <br />). Because of fuel loading i patterns and other factors, one quadrant may see a higher burnup rate as '

compared to other quadrants. Upon RCCA insertion, the Xenon transient induced is in part related to burnup; it may also be driven by secondary side phenomena.

The indicated QPTR was perhaps slightly exacerbated _by the out-of-calibration

. condition of the NIS. However, for the most-part, the indicated quadrant power tilt was real and not merely indicate'd,-being driven by Xenon production /burnup  ;

and other factors.

The QPTR Limiting Condition for Operation (LCO) states that thermal power must ,

be decreased at least 3% from RTP for each 1% of indicated QPTR in excess of 1 and that the Power Range Neutron Flux-High Trip Setpoints-must.be decreased i

!- similarly within the next four hours. This LC0 ensures that peaking factors j l (heat flux hot channel- factor and enthalpy rise hot channel factor) remain l l within permissible limits. The maximum value of QPTR measured was 1.0266, j

.approximately 3% in excess of 1 (one). Thus, the maximum permissible RTP during l l this period was 91%. Due to the Unit runback, power did not exceed j

, approximately 74% (thermal best estimate) during this period of time. Also,_

l since the QPTR was only in excess of 1.02 for 3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> and 50 minutes, the NIS adjustments were not required to be performed. Catawba Unit 1 was in compliance with the LCO. I The health and safety of the public were unaffected by this incident. 1 i

Neh4 ,CFOs 1980*520 589-60070 l