ML20170A405

Independent Spent Fuel Storage Installation Updated Decommissioning Safety Analysis Report, DSAR-7.5, Rev. 1, Instrumentation and Control, Instrumentation Systems

ML20170A405
Person / Time
Site:	Fort Calhoun, 07100256
Issue date:	04/30/2020
From:	Omaha Public Power District
To:	Office of Nuclear Reactor Regulation, Office of Nuclear Material Safety and Safeguards
Shared Package
ML20170A380	List: LIC-20-0005, Independent Spent Fuel Storage Installation, Technical Specification Basis ML20170A382 ML20170A383 ML20170A384 ML20170A385 ML20170A387 ML20170A388 ML20170A389 ML20170A390 ML20170A391 ML20170A392 ML20170A393 ML20170A394 ML20170A395 ML20170A396 ML20170A397 ML20170A398 ML20170A399 ML20170A400 ML20170A401 ML20170A402 ML20170A403 ML20170A404 ML20170A405 ML20170A406 ML20170A408 ML20170A409 ML20170A410 ML20170A411 ML20170A412 ML20170A414 ML20170A415 ML20170A416 ML20170A417 ML20170A418 ML20170A419 ML20170A420 ML20170A421 ML20170A422 ML20170A423 ML20170A424 ML20170A425 ML20170A426 ML20170A427 ML20170A428 ML20170A429 ML20170A430 ML20170A431 ML20170A432 ML20170A433 ... further results
References
LIC-20-0005
Download: ML20170A405 (5)

Text

Page 1 of 5 DSAR-7.5 Instrumentation and Control Instrumentation Systems Rev 1 Safety Classification: Usage Level:

Safety Information Change No.: EC 70091 Reason for Change: Remove EOF and TSC from DSAR Preparer: J. Carlson Fort Calhoun Station

DSAR-7.5 Information Use Page 2 of 5 Instrumentation Systems Rev. 1 Table of Contents 7.5 Instrumentation Systems .............................................................................................. 3 7.5.1 Process Instrumentation .................................................................................... 3 7.5.1.1 Design Bases........................................................................................ 3 7.5.1.2 System Description ............................................................................... 3 7.5.2 Deleted............................................................................................................... 3 7.5.3 Deleted............................................................................................................... 4 7.5.4 Deleted............................................................................................................... 4 7.5.5 Plant Computer (ERF System) ........................................................................... 4 7.5.5.1 Design Bases........................................................................................ 4 7.5.5.2 System Description ............................................................................... 4 7.5.5.3 User Interface Description .................................................................... 5 7.5.5.4 Program Functions ............................................................................... 5 7.5.6 Deleted............................................................................................................... 5

DSAR-7.5 Information Use Page 3 of 5 Instrumentation Systems Rev. 1 7.5 Instrumentation Systems 7.5.1 Process Instrumentation 7.5.1.1 Design Bases The process instrumentation measures the Spent Fuel Pool temperature and level and the Missouri River level.

7.5.1.2 System Description The process instrumentation described below is associated the river and Spent Fuel Pool:

Temperature Temperature measurements of the Spent Fuel Pool are made with precision resistance temperature detectors (RTDs) and installed at multiple depths. The RTDs are connected to the Distributed Control System (DCS) which provides readout on multiple DCS workstations located in the Control Room.

Level Spent Fuel Pool level is indicated locally using a pressure gauge connected to a bubbler system. A redundant pair of guided wave radar level transmitters (contacting) are connected to the DCS.

Spent Fuel Pool level indication is available on multiple Control Room DCS workstations.

Missouri River level is provided by a pressure transmitter connected to a bubbler system and non-contacting radar level instrumentation.

These instruments are connected to the DCS. River level indication is available on multiple Control Room DCS workstations.

7.5.2 Deleted

DSAR-7.5 Information Use Page 4 of 5 Instrumentation Systems Rev. 1 7.5.3 Deleted 7.5.4 Deleted 7.5.5 Plant Computer (ERF System) 7.5.5.1 Design Bases The Emergency Response Facilities (ERF) System is used to monitor and log plant parameters and equipment status.

The function of the computer is to assimilate plant data. The computer provides both a record of plant data and a means of readily providing the operator with information of the following type:

The current status of certain plant switches, relay contacts, values, or plant parameters The displayed value or trend of selected plant parameters or calculated values 7.5.5.2 System Description The computer is a real time digital processing system which collects and organizes plant data for reference and display in the Control Room. The ERF computer is composed of a Foxboro IA Distributed Control System (DCS) and redundant DEC Alpha host computers.

The Foxboro IA DCS performs the data acquisition and critical timing functions (such as sequence of events). The DEC Alpha hosts perform most of the computations and provides the user interface.

User interaction with the computer is through the host. Display selections and other system options are made through the host user interface. The host controls storage of on-line history files and audit trails. It also performs other system functions, such as security protection and communication with external data systems.

The system provides supplementary information for assistance in plant status and provides logic for automatic identification and alarm of off-normal conditions.

The system scans numerous analog inputs (flow, temperature, pressure and level), and digital inputs (including the position of valves, relay contacts, circuit breakers and switches). It provides indication and alarm of off-normal conditions.

An analog input can be simultaneously selected for direct observation on a two pen recorder; two such recorders are provided.

DSAR-7.5 Information Use Page 5 of 5 Instrumentation Systems Rev. 1 7.5.5.3 User Interface Description The system contains numerous workstations to provide communication between the user and the computer. The computer executes various functions in response to commands entered at the workstations.

7.5.5.4 Program Functions Scanning and Display The computer system checks digital inputs from valves, relay contacts and position switches and initiates an alarm in the event of an improper change in status.

The system also checks analog inputs for the following:

Operability of sensors and instrument transmitters. Signal in proper range Comparison of sensor output to alarm setpoints for alarm initiation Calculations The system performs functions necessary for conversion of inputs to engineering units (linearization of thermocouple inputs, square root extraction, integration and averaging).

The computer performs functions necessary for conversion of inputs to engineering units and preparation of the plant performance calculations, e.g., linearization of thermocouple inputs, scale factoring, zero-suppression, square root extraction, integration and averaging.

7.5.6 Deleted