ML17318A123
| ML17318A123 | |
| Person / Time | |
|---|---|
| Site: | Waterford  |
| Issue date: | 11/16/2017 |
| From: | Entergy Operations |
| To: | April Pulvirenti Plant Licensing Branch IV |
| Pulvirenti A | |
| References | |
| EPID L-2017-LRM-0051 | |
| Download: ML17318A123 (24) | |
Text
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ESFAS SPV Elimination Pre-Submittal Meeting
Introductions
John Jarrell - Regulatory Assurance Manager Maria Zamber - Regulatory Assurance Jason Laque - Project Manager Miguel Barreto - Design Engineer Griff Finkenaur - Entergy Contract Support William Steelman - Entergy Contract Support 2
ESFAS SPV Elimination Pre-Submittal Meeting
- ESFAS Design
- Adverse Condition - Single Point Vulnerability
- Technical Specification Change 3
Agenda
ESFAS Design
- The PPS can be broken down into two subsystems;
- Reactor Protection System (RPS)
- Engineering Safety Features Actuation System (ESFAS)
- The ESFAS generates actuation signals for the ESF and ESF support systems to mitigate the consequences of accident conditions.
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ESFAS Design The following is a list of the ESFAS signals:
- Safety Injection Actuation Signal (SIAS)
- Containment Isolation Actuation Signal (CIAS)
- Containment Spray Actuation Signal (CSAS)
- Main Steam Isolation Signal (MSIS)
- Recirculation Actuation Signal (RAS)
ESFAS Design 6
Adverse Condition
- Main Steam Isolation Signal (MSIS)
- K305A or B and K313A or B Actuation Relay failure will close Main Steam Isolation Valve (MSIV), Feedwater Isolation Valve (FWIV), Feedwater Regulating Valve, and Feedwater Startup Regulating Valve
- Closure of a single MSIV will result in asymmetric steam generator transient (ASGT), resulting in a CPC high differential cold leg temperature trip and a loss of thermal margin.
- Closure of both MSIVs will result in a complete loss of the secondary heat sink requiring a reactor trip on high pressurizer pressure.
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Adverse Condition
- Containment Spray Actuation Signal (CSAS)
- K114A or B Actuation Relay failure will close Component Cooling Water (CCW) flow to the non-critical loop.
- This will result in loss of Component Cooling Water (CCW) flow to the Reactor Coolant Pumps (RCPs) and the Control Element Drive Mechanism (CEDM) cooling coils.
Loss of seal cooling to the RCP can result in serious RCP seal damage with the potential for a small break LOCA.
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1 out of 1 Logic 9
Resolution - Modify the MSIS and CSAS Circuit
- Revise the ESFAS Actuation Circuit from a 1 out of 1 logic to a parallel 2 out of 2 logic.
- Removed the SPV from the circuit
- Parallel 2 out of 2 logic meets the Reg Guide 1.22 requirements
- Add a LED Test Fixture with a LED to illuminate when a ESFAS Actuation Relay Contact closes.
- Provides indication of failed relay
- Provides safe means to test quarterly without need for intrusive maintenance using meters for voltage and continuity checks 10
Resolution - Parallel 2 out of 2 Logic 11 Actuation Relay Contacts
12 125VDC Test Push Button Testing LED Lights
13 125VDC Test Push Button Testing of Actuation Relay
14 125VDC Test Push Button Testing of Actuation Relay
15 125VDC Test Push Button ESFAS Actuation
Proposed Design (MSIS) 16 36VDC Power Supply 36VDC Power Supply LOCKOUT RELAY POWER (SUBGROUP)
CIRCUIT BREAKER MANUAL TRIP ESFAS INITIATION RELAY CONTACTS SSR1A SSR3A LOCKOUT RELAY CONTACT TO ANNUNCIATOR CIRCUIT 120VAC VITAL BUS A 120VAC VITAL BUS B 36VDC Power Supply 36VDC Power Supply LOCKOUT RELAY POWER (SUBGROUP)
CIRCUIT BREAKER MANUAL TRIP LOCKOUT RELAY CONTACT TO ANNUNCIATOR CIRCUIT 120VAC VITAL BUS B 120VAC VITAL BUS A RESET RESET BLOCKING DIODES BLOCKING DIODES K305 K313 K519 K519 K520 K605 K613 MAIN STEAM ISOLATION SIGNAL (MSIS A)
K404 K504 K819 K820 K105 K805 K205 K705 K819 INTERPOSING RELAY INTERPOSING RELAY K623 K723 K623 K723 SSR2A SSR4A ESFAS INITIATION RELAY CONTACTS FW-166B FW-173B K313A 1H 1J K404A 1H 1J K105A 1H 1J K205A 1H 1J FW-184B K313A 1F 1E K404A 1F 1E K105A 1F 1E K205A 1F 1E MS-124B (SV-1A)
K313A 2B 2C K404A 2B 2C K105A 2B 2C K205A 2B 2C MS-124B (SV-2A)
K313A 2E 2F K404A 2E 2F K105A 2E 2F K205A 2E 2F FW-184A K305A 1C 1B K404A 1C 1B K105A 1C 1B K205A 1C 1B ac (limit switch - closed when valve is open)
FW-184A (COX/LC)
K305A 1E 1F K404A 3E 3F K105A 3E 3F K205A 3E 3F COX LC (closed when valve is open)
FW-166A FW-173A K305A 1H 1J K404A 2H 2J K105A 2H 2J K205A 2H 2J MS-124A (SV-2A)
K305A 2M 2L K404A 2M 2L K105A 2M 2L K205A 2M 2L MS-124A (COX/LC)
K305A 2E 2F K404A 4E 4F K105A 4E 4F K205A 4E 4F COX LC (closed when valve is open)
MS-124A (SV-1A)
K305A 2C 2B K404A 3C 3B K105A 3C 3B K205A 3C 3B K504 K705 K805 K820 K613 K605 K520 K511 Lamp Test Push to Test 6VDC Test Power Supply
+
Initiate K305 Full Actuation (MSIS K411)
Initiate K313 Initiate K105 Initiate K404 Initiate K205 Rotary Test Switch (existing) 125 VDC
+62.5 VDC
-62.5 VDC K411 K411 36VDC LED Power (105 - 140)
K212 K212 K411 K212 K411 K212 36VDC 2A Fuse 2A Fuse To CSAS LEDs To CSAS LEDs TB LTF 3 TB LTF 4 TB LTF 5 TB LTF 6 TB LTF 7 TB LTF 8 TB LTF 9 TB LTF 10 TB LTF 11 TB LTF 12 TB LTF 13 TB LTF 14 TB LTF 15 TB LTF 16 TB LTF 17 TB LTF 18 TB LTF 19 TB LTF 20 TB LTF 21 TB LTF 22 TB LTF 1 TB LTF 2 K411 K212 K712
Proposed Design (CSAS) 17 36VDC Power Supply 36VDC Power Supply LOCKOUT RELAY POWER (SUBGROUP)
CIRCUIT BREAKER MANUAL TRIP ESFAS INITIATION RELAY CONTACTS LOCKOUT RELAY CONTACT TO ANNUNCIATOR CIRCUIT 120VAC VITAL BUS A 120VAC VITAL BUS B 36VDC Power Supply 36VDC Power Supply LOCKOUT RELAY POWER (SUBGROUP)
CIRCUIT BREAKER MANUAL TRIP LOCKOUT RELAY CONTACT TO ANNUNCIATOR CIRCUIT 120VAC VITAL BUS B 120VAC VITAL BUS A RESET RESET BLOCKING DIODES BLOCKING DIODES K405 K621 K621 K622 Containment Spray Actuation Signal (CSAS A)
K406 K818 K817 K114 K208 K818 SSR2A SSR4A ESFAS INITIATION RELAY CONTACTS K506 K708 K814 K817 K505 K622 SSR1A SSR3A CC-710 K208A 4L 4M K114A 4L 4M K406A 4L 4M K405A 4L 4M Lamp Test 125 VDC
+62.5 VDC
-62.5 VDC LED Power (105 - 140)
K505 K506 K814 K708 K712 Push to Test 6VDC Test Power Supply
+
Initiate K405 Full Actuation - Initiate K212 Initiate K406 Initiate K114 Initiate K208 Rotary Test Switch (existing)
K212 36VDC K411 K411 K212 K411 K212 From MSIS LEDs From MSIS LEDs TB LTF 23 TB LTF 24 K411 K212 K511
ESFAS Aux Relay Cabinet Layout Concept 18 Side View LED Test Fixture 13"x24" (existing) 13"x24" (existing) 4 3
2 1
5 6
7 8
144" 90" New LED Test Fixture 24" HIGH, 20" WIDE, 8" DEEP, OVERALL FLANGES:
27.33" X 25.33" 60" 40" 20" 10-1/2 Notes
- 1. Information developed from drawing 1564-6336 and manual TD-C490.0645
- 2. Cabinet weight is 13,000lbs
- 3. One cabinet shown.
Both Cabinet A and B are identical 56" 8
7 6
5 Internal Cross members Door interior 8"
A A
View A-A ESFAS BAY 8 (Side View)
LED Test Fixture 19
Technical Specifications Change 20
ØRemove ESFAS Relays K305, K313, K114 from Technical Specifications Table 4.3-2 note 3
ØThis will change the frequency of testing of ESFAS Relays K305, K313, K114 (and the added MSIS &
CSAS Relays) to the frequency established by the Surveillance Frequency Control Program
ØThe relay surveillance frequency will be changed to be tested during power operation.
Technical Specifications Change 21 Current Technical Specification Table 4.3-2 Note 3
Technical Specifications Change 22 Revised Technical Specification Table 4.3-2 Note 3
Closing
- Waterford 3 is being proactive with eliminating the identified Single Point Vulnerability in the ESFAS circuity.
- The proposed ESFAS circuitry modification will:
- Eliminate identified Single Point Vulnerability
- Allow for non-intrusive, safe method for testing on-line
- Will identify a failure of an ESFAS Actuation Relay
- Will comply with Reg. Guide 1.22
- Expected submittal date is December 5th, 2017.
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Conclusion
- Thank you for your time and attention.
- Questions?
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