Protecting People and the EnvironmentUNITED STATES NUCLEAR REGULATORY COMMISSION
LICENSEE: AMETEK/DIXSON
SITE: AMETEK/DIXSON EN NUMBER:30312
DOCKET: EVENT DATE: 04-16-96
RX TYPE: EVENT TIME: 17:30
VENDORS: NOTIFY DATE: 04-18-96
EMERGENCY CLASS: N/A REGION: 4 STATE: CO TIME: 18:28
OPS OFFICER: JOHN MacKINNON
10 CFR SECTION: CDEG 21.21(c)(3)(i) DEFECTS/NONCOMPLIANCE
AMETEK/DIXSON PROSERIES BARGRAPH MODELS SA101A, SA202P, SN101P,
AND SN202P UNITS CAN POTENTIALLY INDICATE AN ERRONEOUS UNDER
RANGE CONDITION AT A VERY SPECIFIC INPUT POINT.
THE FOLLOWING PORTION OF THIS TEXT IS TAKEN FROM A FACSIMILE
RECEIVED FROM AMETEK/DIXSON, LOCATED IN GRAND JUNCTION, CO.
" ... AN APPARENT ANOMALY HAS BEEN IDENTIFIED IN THE
AMETEK/DIXSON PROSERIES BARGRAPH MODELS SA101P, SA202P, SN101P,
AND SN202P.
THE INDICATION CAUSED BY THE ANOMALY IS AS FOLLOWS:
DEPENDING ON THE CONFIGURATION OF THE SPECIFIC BARGRAPH, i.e.
CURRENT OR VOLTAGE, THE UNIT CAN POTENTIALLY INDICATE AN
ERRONEOUS UNDER RANGE CONDITION AT A VERY SPECIFIC INPUT POINT.
EXAMPLE, IF THE UNIT IS CONFIGURED FOR 4/20mA RANGE, THE ANOMALY
CAN OCCUR AT APPROXIMATELY 91% OF SPAN.
"WHEN THE CONDITION OCCURS, THE BARGRAPH WILL INDICATE A ZERO
READING ON THE BARGRAPH PORTION, INDICATE DASHES ON THE DIGITAL
DISPLAY PORTION, AND THE RELAYS (IF USED) WILL TRACK THIS
INDICATION. THIS IS TYPICALLY A MOMENTARY CONDITION, AND THE UNIT
IMMEDIATELY RETURNS TO NORMAL OPERATION AFTER THE ANOMALOUS
CONDITION STOPS.
THIS IS A VERY UNCOMMON CONDITION, AND IF THE CONDITION OCCURS,
THE RESPONSE BY THE OPERATOR IS UNKNOWN TO AMETEK/DIXSON SINCE
THE BARGRAPHS ARE USED IN VARYING APPLICATIONS. IT IS BELIEVED
THAT AN INCORRECT RESPONSE WOULD BE THE WORST CASE CONDITION,
HOWEVER, ITS LOW PROBABILITY OF OCCURRENCE AND VERY SHORT TERM
DURATION WOULD TEND TO LIMIT THIS LIKELIHOOD."
AMETEK/DIXSON IS CURRENTLY NOTIFYING THE AFFECTED USERS (EXPECTED
COMPLETION DATE IS 4/22/96).
THE FOLLOWING IS A LIST OF POWER PLANTS THAT HAVE RECEIVED THE
CLASS 1E "PRO" SERIES INDICATORS:
ENTERGY OPERATIONS: ARKANSAS NUCLEAR ONE
FLORIDA POWER AND LIGHT: ST. LUCIE NPP
FLORIDA POWER AND LIGHT: CRYSTAL RIVER UNIT 3
NORTHEAST UTILITY: MILESTONE SITE
OMAHA PUBLIC POWER DISTRICT: FORT CALHOUN STATION
GEORGIA POWER COMPANY: PLANT HATCH
