ML19321A442
| ML19321A442 | |
| Person / Time | |
|---|---|
| Site: | Comanche Peak  |
| Issue date: | 06/27/1980 |
| From: | Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV) |
| To: | Gary R TEXAS UTILITIES ELECTRIC CO. (TU ELECTRIC) |
| References | |
| NUDOCS 8007230370 | |
| Download: ML19321A442 (1) | |
Text
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UNITED STATES
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NUCLEAR REGULATORY COMMISSION 3 i ' ft REGloN IV i'
S 611 RYAN PLAZA DRIVE, SUITE 1000 E
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l ARLINGTON, TEXAS 76012
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n June 27, 1980 In Reply Refer To:
RIV Docket Nos.
50-445/IE Bulletin No. 80-16 50-446/IE Bulletin No. 80-16 Texas Utilities Generating Company ATIN:
Mr. R. J. Gary, Executive Vice President and General Manager 2001 Bryan Tower Dallas, Texas 75201 Gentlemen:
Enclosed is IE Bulletin No. 80-16 which requires action by you with regard to your power facilities with an operating luense or a construction permit.
Also enclosed is IE Circular 80-16 for information.
In order to assist the NRC in evaluating the value/ impact of each Bulletin on licensees, it would be helpful if you would provide an estimate of the manpower expended in conduct of the review and preparation of the report (s) required by the Bulletin. Please estimate separately the manpower associated with corrective actions necessary following identification of problems through the Bulletin.
Should you have any questions regarding the Bulletin or Circular or the actions required of you, please contact this office.
Sincerely, i
f o
h.
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Karl V. Seyfrit Director
/
Enclosures:
)
1.
IE Circular No. 80-16 3.
Lists of Recently Issued IE Bulletins and Circulars I
r 800723o 3 70
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1 i
SSINS No.: 6820 Accession No.:
UNITED STATES 8005050066 NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT I
WASHINGTON, D.C.
20555 June 27, 1980 IE Bulletin No. 80-16 POTENTIAL MISAPPLICATION OF ROSEMOUNT INC. MODELS 1151 AND 1152 PRESSURE TRANSMITTERS WITH EITHER "A" OR "D" OUTPUT CODES Description of Circumstances The NRC has recently been advised through 10 CFR 21 reports that a potential misapplication problem exists on Rosemount Inc. Models 1151 and 1152 pressure transmitters with either "A" or "D" output codes.
The pressure transmitters are used in both pressure and differential pressure applications.
Applications include pressurizer pressure monitoring (pressure transmitters) and reactor vessel level monitoring (differential pressure transmitters).
The potential misapiplication problem occurs when the above specified transmitters are exposed to excessive over or reverse pressures.
These pressures can result in ambiguous signal outputs from the transmitter to control and/or indication components.
These ambiguous signals could result in erroneous control action, such as an open signal to a solenoid valve rather than a closed signal, or an erroneous indication signal, such as an indication in the normal operating range when a pressure outside the normal range actually exists. contains Rosemount Inc.'s technical description of the potential application problems for Pressure Transmitters Model 1152.
This information is applicable to Model 1151 Pressure Transmitters also.
This information includes the reasons for the saloperation of the transmitters,'a typical pressure versus current output curve and examples of the results of the mal-operations.
Available information indicates that the problem was reported to each customer who was furnished the subject transmitters by Rosemount Inc.
Actions to be Taken by Licensees of Power Reactor Operating Facilities and Holders of Construction Permits:
1 1.
Determine if your facility has installed or plans to install Rosemount Inc. Model 1151 or 1152 pressure transmitters with output codes "A" or "D" in any safety-related application.
2.
If it is determined that your facility has the transmitters described in 1 above in any safety-related application, determine whether they can be exposed to input pressures that could result in anomalous output signals during normal operation, anticipated transients or design bases accidents.
If the affected transmitters can be exposed to input pressures that could result in anomalous output signals, perform a worst case analysis to determine whether the anomalous signals could result in violating any i
IE Bulletin No. 80-16 June 27, 1980 Page 2 of 2 9
design basis assumption.
The safety-related application shall include 4
control, protective or indication functions.
If any safety-related application does not conform to the above requirements, address the basis for continued plant operation until the problem is resolved, and provide an analysis of all potential adverse system effects which could occur as a result of a postulated pressure transmitter maloperation described in of this bulletin.
In each instance, the analysis should include the effects of postulated transmitter maloperation as it relates to indica-tion, control and protective functions.
The analysis shall address both incorrect automatic system operation and incorrect operator actions caused by erroneous indications.
Address the conformance to IEEE 279, Section 4.20, in your analysis.
Include in your analysis the following table:
a.
Complete model number.
b.
Transmitter range limits.
c.
Transmitter range setting.
d.
Range of process variable measured for (1) normal, and (2) accident conditions.
Values of process variable which could produce anomalous indication e.
based upon your evaluation.
f.
Service / function.
3.
Submit a complete description of all corrective actions required as a result of your analysis and evaluations, together with the schedule for accomplishing the corrective actions.
4.
Provide the response in writing within 30 days for facilities holding an operating license or are NTOL applicants
- and within 60 days for those facilities holding construction permits.
Reports shall be submitted to the Director of the appropriate NRC Regional Office with copies forwarded to the U.S. Nuclear Regulatory Commission, Office of Inspection and Enforcement, Division of Reactor Operations Inspec-tion (for facilities holding an operating license), or Division of Reactor Construction Inspection (for facilities holding a construc-tion permit), Washington, D.C. 20555.
- The plants that are the subject of the near-term operating license reviews North Anna 2, Salem 2, Sequoyah 1 & 2, McGuire 1 & 2, Diablo 1 & 2, and are:
Zimmer.
Approved by GAO, B180225 (R0072); clearance expires July 31, 1980.
Approval was given under a blanket clearance specifically for identified generic problems.
Enclosure:
Extract from Rosemount Inc.
letter to NRC dated Jun.c 6, 1980
1
\\
Encl. I to Bulletin 80-16 EXTRACT FROM ROSEMOUNT, INC.
LETIER.TO NRC DATED JUNE 6, 1980 j
)
(1)
Name and address of the individual or individuals informing the Commission.
Not. Applicable.
(ii)
Identification of the facility, the activity, or the basic component supplied for such. fac414ty or such activity within the United States which is affected by the potential application problem.
Rosemount Model 1152 Pressure Transmitters with output codes "A" or
- nyer, (iii) Identification of the firm making the report.
Rosemount Inc.
12001 W. 78th St.
Eden Prairie,. MN.
55344 (iv)
Nature of the potential applications problem.
Rosemount's Model 1152 pressure transmitter provides a specified linear output, of 4 to 20 mA throughout the calibrated range of operation.
The transmitter output is not specified by Rosemount for pressures outside of' the enlibrated range of operation.
It has been observed in a limited number of transmitters that an output between 4 and 20 mA can occur with certain. input pressures outside of the calibrated range.
These ambiguous outputs can occur in both, an over pressure condition and a reverse pressure condition. Both conditions arise when the center diaphragm of the pressure sensor bottoms out agaimat either of the fixed capacitor plates. In each case the normal capacitance signal becomes a very high capacitance signal which affects the operation of the electronic circuit.
For the over pressure condition, the effect of the high capacitance from the sensor is a modulated output on the oscillator circuit which may cause the output current of the transmitter to drop below 20 mA.
In a, limited sample size, the ambiguous output during this over pressure condition occurred in 5% of the transmitters ar ambient conditions.
Referring to the attached graph,_ this does not occur until the over pressure conclicinn is.2 140% of the upper range limit regardless of span. At that point a discontinuity can occur with the output current instantaneously decreasing to less than 20 mA.
As an avample of this potential applications problem, the upper range limit of a range 5 1152 differential pressure transmitter (Model 1152DPSA22) is 750"H.30.
The rangeofthispressuretransmittercanbesetfrom0to150"Hjo.
If the ambiguous output in the over pressure condition is to occur, it will occur at 140% or more of the upper range limit or, in this case, at pressures.x 1050"H.,0 (750"H 0 x 1.4).
The transmitter than could give an output less than 20 mA at a' pressure that is, in this avamnie, seven
. )
i cines (1050"H,0 + 150"H O) the upper range value.
Note that the 2
s1gnificant figure for use in determining the pressure above which an ambiguous output can occur is the specified upper range limit (750" H O in this example) not the customer selected upper range value (2I50"H O in this example)'
2 For the reversa pressure condition, the effect of the high capacitance from the sensor is the oscillator circuit drawing more current which may cause the output. current of the transmitter to exceed 4 mA.
In a limited sample size, the ambiguous output during this reverse pressure condition occurred in 55% of the transmitters at ambient conditions.
Referring to the attached graph, this does not occur until the reverse pressure condition exceeds 140% of the upper range limit regardless of the span., At this point the output may exceed 4 mA.
As an avample of this potential applications problem consider the range 5 differential transmitter in the previous paragraph.
If the ambiguous output in the reverse pressure condition is to occur, it will occur at 140% or more of the upper ranga limit, or in this case at reversed pressures 2.1050" O (750"H 0 x 1.4).
The transmitter then could give an output greater 3
4 mA 'at a pressure that is, in this example, seven times (1050" 0 + 150" H O) the upper range value, but reversed.
Also note that 2
th absolute pressure units a reverse pressure is not possible since the low pressure side of the call is evacuated.
With gage units a reverse pressure is possible only if a vacuum is present on the connected part since the low pressure side of the cell is vented to ambient atmosphere.
Since the
v4
reverse pressure would be one atmosphere, only range 3 and 4 gage units could obtain a reverse pressure exceeding 140% of the upper range limit.
Due-to the effects of radiation or elevated temperature, we believe that the frequency of occurrence of the ambiguous output will be greater in
- a. radiated. or an elevated temperature-environment than was experienced in. our limited sample size testing, which was in a non-radiated ambient temperatura environment.
Af ter the occurrence of an ambiguous output from an ~over pressure or a reverse pressure condition,. the trwamitter will return to specified operation.when the input pressure returns to the calibrated range, provided the over pressure or reverse pressure was within the
==v4n=== pressure limits specified by Rosemount.
(v)^
The date on which the information of the potencimi applications problem was obtained.
Amamled to March 6,1980.
3-(vi)
The number and location of all in use at, supplied for, or being supplied for one or more facilities or activities subject to the regulations in this part.
Not applicable.
(vii) The corrective action recommended to negate this potential application problem.
The safety system should be analyzed in view of this supplementary report to determine if a potential applicreion problem exists and appropriate corrections to the safety sy. stem should be implemented.
(viii). Any. advice related to the defect or failure to comply about the facility, activity, or basic component that has been, is being, or will be given to purchasers or licensees.
Not applicable.
Attachment 1
i
-~>
POSSIBLE
-0UTPUT AMelGUOUS
~
CURRENT OUTPtit l
-20 m e- - - - - - - - - -
~
-l------
l u
m
-FOUR DIFFERENT Call 8 RATED SPANS
~
POSSIBLE AMBIGUOUS OUTPUT
-4me-------------------------q
-MO%
EGATIVE UPPER 14 0 %
f l
s RANGE TIMES TIMES UPPER LIMIT URL URL RANGE
, LIMIT LOW SIDE PRESSURE )HIGH SIDE PRESSURE ( )HIGH SIDE PRESSUREM SIDE PRESSURE INPUT PRESSURE
.u
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SSINS No.: 6830 Accession No.:
UNITED STATES 8005050067 NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT 4
WASHINGTON, D.C.
20555 l
June 27, 1980 IE Circular No. 80-16 OPERATIONAL DEFICIENCIES IN ROSEMOUNT MODEL 510DU TRIP UNITS AND MODEL 1152 PRESSURE TRANSMITTERS Description of Circumstances:
The NRC has recently been advised through a 10 CFR 21 report that operational deficiencies exist in Rosemount Inc. Model 510DU trip units and Model 1152 pressure transmitters as follows:
MODEL 510DU TRIP UNITS The 510DU trip units have common mode failures of two switches; S1 in the trip status output, LED logic circuit and S2 in the trip output logic circuit.
The trip units involved are those with serial numbers 3001 to 4203.
The 510DU units having serial numbers within-this range that are not trip units are not affected (i.e., Card Files, Readout Assemblies, Calibration Units, etc.).
Malfunction of these switches appears as an open circuit in the output logic upon receipt of an actual trip signal.
Switch (S2) failure could result in failure to automatically activate a safety function.
MOCEL 1152 PRESSURE TRANSMITTERS The model 1152 pressure transmitters have a common mode failure of a capacitor wheg the transmitter operating environmental temperature is greater than 175 F, and when the damping potentiometer is rotated clockwise.
The failure results in a decrease in transmitter output current of up to 10 percent of the correct current. For example, when the transmitter is used in an indica-tion circuit, the parameter indication would be correspondingly lower than the correct value if the capacitor failure occurred. The failure potentially involves all pressure transmitters with the following model designations:
Rosemount Pressure Transmitter Models:
1152 E
T0280 1152 E
T0445 1152 E
T0400 Available information indicates that the problems outlined above have been reported to each customer who was furnished the Model 510DU trip units and Model 1152 pressure transmitters.
LE Circular No. 80-16 June 27, 1980 Page 2 of 2 RECOMMENDED ACTION FOR LICENSEES AND HOLDERS OF CONSTRUCTION PERMITS All licensees of nuclear power reactors and holders of construction permits should be aware of the potential problems discussed above.
It is recommended that the following actions be taken:
1.
Determine if your facility has installed or plans to install the Rosemount Model 510DU trip units and/or the pressure transmitters described herein in any safety-related equipment.
2.
If it is determined that your facility has installed or plans to install any of the affected units described herein, contact the supplier for performance of the required modifications to the units to resolve the problems.
3.
Modifications should be performed on all affected units prior to plant operation.
If the affected units are installed in plants that are operating, the following actions are recommended for continued operation until the units are modified.
a.
510DU Trip Units
\\
A functional test verifying proper operation of the trip units should be perfo med.
b.
Model 1152 Pressure Transmitters On pressure transmitters that are affected and that may be subjected to operating environmental temperatures greater than 175'F, the transmitters sheuld be operated with the damping potentiometer (R12) in the fully counterclockwise position.
CAUTION The circuit output should be monitored to assure that no action detrimental to operation results from placing R12 in the counter-clockwise position, such as spurious tripping caused by unstable operation.
No written response to this circular is required.
If you require additienal information regarding this matter, contact the Director of the appropriate NRC Regional Office.
IE Bulletin No. 80-16 June 27, 1980 RECENTLY ISSUED IE BULLETINS Bulletin Subject Date Issued Issued To No.
80-08 Examination of Containment 4/7/80 All power reactors with a Liner Penetration Welds Construction Permit and/or Operating License (OL) 80-09 Hydramotor Actuator 4/17/80 All power reactor Deficiencies operating facilities and holders of power reactor construction permits (cps) 80-10 Contamination of 5/6/80 All po-ar reactor Nonradioactive System and facilities with an Resulting Potential for Operating License (3L)
Unmonitored, Uncontrolled or Construction Permit Release to Environment (CP) 80-11 Masonry Wall Design 5/8/80 All power reactor facilities with an Operating License (OL),
except Trojan and holders of a Construction Permit (CP) 80-12 Decay Heat Removal System 5/9/80 Each PWR with an Operability Operating License (OL) 80-13 Cracking In Core Spray 5/12/80 All BWR's with an Operating License (OL) 30-14 Degradation of Suram 6/12/80 All BWR's with an Discharge Volume Operating License (OL)
Capability 80-15 Possible Loss Of Hotline 6/18/80 All nuclear facilities With Loss Of Off-Site holding Operating Licenses Power (OLs)
Enclosure
IE Circular No. 80-16 June 27, 1980 RECENTLY ISSUED IE CIRCULARS Circular Subject Date Issued To No.
Issued 80-10 Failure to Maintain 4/29/80 All holders of Reactor Environmental Qualifi-Operating Licenses (OLs) cation of Equipment and Construction Permits (cps) 80-11 Emergency Diesel Generator 5/13/80 All holders of a power Lube Oil Cooler Failures reactor Operating License (OL) or Construction Permit (CP) 80-12 Valve-Shaft-To-Actuator 5/14/80 All holders'of Reactor Key May Fall Out of Place Operating Licenses (OLs)
When Mounted Below and Construction Permits Horizontal Axis (cps) 80-13 Grid Strap Damage in 5/18/80 All holders of Reactor Westinghouse Fuel Operating Licenses (OLs)
Assemblies and Construction Permits (cps) 80-14 Radioactive Contamination 6/24/80 All holders of Power and of Plant Demineralized Research Reactor Licensees Water System and Resultant (Operating and Construction Internal Contamination of Permits), and Fuel Cycle Personnel licensees 80-15 Loss of Reactor Coolant 6/20/80 All power reactor facilities Pump Cooling and Natural with an Operating License (OL)
Circulation Cooldown or Construction Permit (CP)
Enclosure l
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