ERDADS Flashcards
What is the function of ERDADS/SAS?
- Parameters used to evaluate plant indications during Emergency / Off-Normal conditions
- Can’t drive plant with ERDADS, used for management/NRC information and easy transmission
- ERDADS is a Distributed Control System (DCS) whose information is available from any control room Application Workstation (AW) via the Plant Data Network (PDN)
- ERDADS: Emergency Response Data Acquisition & Display System
- SAS: Safety Assessment System
- SPDS: Safety Parameter Display system - a subsystem of ERDADS/SAS
What is the Design Basis of ERDADS/SAS?
- The Safety Assessment System of the St. Lucie Plants is designed to fulfill the requirements of:
a) NUREG 0696, “Functional Criteria For Emergency Response Facilities,” and
b) NUREG 1394, “Emergency Response Data System (ERDS) Implementation” - For a data gathering, storing and display system for the plant control rooms, Technical Support Center, Emergency Offsite Facility, and to the NRC remote facilities.
- Although inputs from safety-related instrumentation are used, there are no safety-related design bases for the ERDADS/SAS system.
Discuss Loss of ERDADS.
- Loss of ERDADS for > 1 hr may be reportable. It may require notification of the NRC within 8 hours, per AP-0010721, “NRC Required Non-Routine Notifications and Reports, Appendix A.”
Discuss ERDADS/SAS Power Supplies.
Unit 1
1C SAS SUP’s:
* Normal Power: MCC 1A1
* DC Backup: 1C Battery Bus
* Alternate Power: MCC 1A1
1D SAS SUP’s:
* Normal Power: MCC 1B1
* DC Backup: 1D Battery Bus
* Alternate Power: MCC 1B1
Unit 2
2A SAS SUP’s:
* Normal Power: MCC 2A1
* DC Backup: 2C Battery Bus
* Alternate Power: MCC 2A1
2B SAS SUP’s:
* Normal Power: MCC 2B1
* DC Backup: 2D Battery Bus
* Alternate Power: MCC 2B1
Discuss SPDS.
Provides plant parameters from which the safety status of operation may be assessed in the:
* Control Room
* Technical Support Center (TSC)
* Emergency Operations Facility (EOF)
- Primary Function: Help operating personnel in the Control Room make prompt assessments of plant safety status (without overloading the operator with too much information)
- The SPDS is a series of displays based on the Safety Function Status (SFS) as presented in EOP-15
Discuss how/why ERDADS/SAS Data is sent to the NRC.
- Using modem connections via the Emergency Response Data System (ERDS)
- NRC Requires Accurate and timely Data on Four Types of Information during an Accident:
a) Core and RCS Conditions to Assess Extent or Likelihood of Core Damage
b) Conditions inside RCB to Assess Likelihood and Consequence of RCB Failure
c) Radioactivity Release Rates to Assess Immediacy & Degree of Danger to Public
d) Met Tower Data to Assess Likely Patterns of Potential or Actual Impact to Public
Discuss ERDADS Interface.
- The standard Red/Green for Open/Closed and On/Off for digital signals used
- DCS color convention on the quality of the parameters:
- White on Green (GOOD)
- Black on Cyan (POOR)
- Blue on White (BAD) or are unavailable (i.e., OFFSCAN or BYPASSED)
Discuss SPDS Displays.
- The SPDS Displays have a Menu titled CSFM (Critical Safety Function Monitoring) Menu and listed on it are 9 individual SFS Displays and 3 Top Level Displays.
- RTGB 104 [204] SPDS FPD should always display the TOP Level Display when not actively used by operators.
- The SPDS display monitor on RTGB 204 shall be dedicated to one of the 3 Top Level Displays in order to meet regulatory requirements for constant monitoring of parameters deemed important to safe plant operation.
What 3 displays are featured by Top Level Displays?
- Critical Safety Function Monitoring (CSFM) Top Level Display
- RCS Heatup and Cooldown Rate Display:
- Refueling Level Display
What information is displayed by the Critical Safety Function Monitoring (CSFM) Top Level Display?
- Pressurizer Pressure and Level
- RCS Hot and Cold Leg Temperatures
- Charging and Letdown Flow
- SG WR Level, SG Pressure
- ECCS Flow
- Plant Mode
- T-cold average
- Power (Linear Range, Wide Range, and SU range)
- Core Exit Temperature
- Number of RCPs running
List the 9 SFS Displays include the following quickly accessible via Buttons/Indicators.
- Reactivity Control
- Maintenance of Vital Auxiliaries
- RCS Inventory Control
- RCS Pressure Control
- RCS & Core Heat Removal Without SIAS
- RCS & Core Heat Removal With SIAS
- RCS & Core Heat Removal With Once-Thru Cooling
- Containment Isolation
- Containment Temperature and Pressure
Discuss Safety Function Status Trees.
- The SFS Displays are to be used by Operations as a EOP-15 diagnostic aid in helping to determine plant safety status at any given moment
- SFS by color codes:
Green (Met - Optimal)
Yellow (Met - Next Preferred)
Orange (Met - Least Preferred)
Red (Not Met) - Each Safety Function follows the logic established by EOP-15 Safety Function Status Check Sheets.
