Lgs Ilt - 4Kv, Dc Power, & Week 6

Front 1

Response of 4KV system to a LOOP

Back 1

4kv bus voltage decreases to < 40% rated voltage

t = 0 bus voltage < 40%
t = 0 D11 Bus undervoltage relay drops out (101-D11 Breaker trips)
t = 0 ALL D11 bus breakers trip except LC transformer breaker
t = 0.5 D11 diesel starts (or if diesel is already running - then D11 breaker closes in)
t = 1 sec -if undervoltage condition still exists and alternate safeguard bus has power 201-D11 breaker Auto CLOSES
t < 10 secs D11 diesel 4kv breaker closes as soon as the ready to load relay energizes.

Front 2

Timeline for a LOCA & LOOP

Back 2

t = 0 D/G Breaker closes
t = 0 All RHR pumps start
t = 3 Load Center Breakers close
t = 7 All Core Spray pumps start
t = 45 ESW pumps start
t = 167 Control Room chillers start (Unit 1 LOCA only)

Front 3

Timeline for a LOCA w/ OOP

Back 3

t = 0 LOCA signal - Diesel starts
t = 0 Load shed (all 4kv loads will trip off)
t = 0 C & D RHR pumps start
t = 3 L.C. Transformer Breaker closes **
t = 5 A & B RHR pumps start
t = 10 A & C Core Spray pumps start
t = 15 B & D Core Spray pumps start
t = 53 ESW pumps start
t = 167 Control Room chillers start

** non safeguard MCC loads will remain tripped off) and must be energized

Front 4

Auto trip of a Diesel Generator Output Breaker (8)

Back 4

(Need ANY of the following):
- Bus lockout relay
- D/G Differential Lockout Relay
- D/G Phase Overcurrent Relay
- D/G Ground Fault Relay
- D/G anti-motoring relay
- Diesel engine tripped
- D/G Operating in parallel with 101 or 201 AND LOCA Signal initiated
- Breaker control switch to TRIP with RSP Transfer SW in NORM

Front 5

Auto closure of a Diesel Generator Output Breaker (8)

Back 5

(Need ALL of the following):
- Diesel Breaker in CONNECTED position
- Associated bus undervoltage condition exists <40%
- Both 101 and 201 Bus Breakers are open
- Either the 101 or 201 Breaker is red flagged
- Diesel Ready to Load Relay energized (>95% voltage and frequency)
- Associated bus lockout relay reset
- Associated diesel lockout relay reset
- Diesel Breaker control switch in Normal

Front 6

Manual closure of a Diesel Generator Output Breaker (6)

Back 6

(Need ALL of the following):
- Diesel Breaker in CONNECTED position
- Diesel Breaker Sync Switch on
-Diesel Ready to Load Relay energized (>95% voltage and frequency)
- Associated bus lockout relay reset
- Associated diesel lockout relay reset
- Diesel Breaker Control Switch to close

Front 7

Auto closure of the 101-D11 Breaker (8)

Back 7

(Need ALL of the following):
- 101-D11 Breaker in the CONNECTED position
- 201-D11 Breaker Control Switch in “normal after close” (red flagged)
- D11 Bus undervoltage present (<40%)
- 1 second time delay following D11 undervoltage
- Normal voltage present (>70%) from 101 Transformer
- D11 Bus Lockout Relays reset
- 101 Transformer Lockout Relay reset
- 201-D11 Breaker is open

Front 8

Auto Trip of the 101-D11 Breaker (4)

Back 8

(Need ANY of the following)
- D11 Bus Lockout Relays operated from:
o Bus Differential Relay
o Bus Phase Overcurrent Relay
o Bus Ground Overcurrent Relay
- 101-D11 Breaker Directional Phase Overcurrent Relay
- 101 Transformer Undervoltage (< 70%)
- 101 Transformer degraded voltage
o 94% for 60 sec. time delay
o 87.5% for 52 sec.
o 94% for 9 sec. With LOCA signal

Front 9

Remote manual closure of 101-D11 Breaker (6)

Back 9

(MCR) (Need ALL of the following):
- 101-D11 Breaker is in CONNECTED position (racked in)
- 101-D11 Sync Switch is on
- D11 Bus Lockouts relays reset (no fault on D11)
- 101 Transformer Lockout relay reset (no fault on 101)
- 201-D11 Breaker is open (cant have both 101 and 201 closed at the same time)
- 101-D11 Breaker Control Switch to Close

Front 10

101-D11 Breaker control from the RSP:

Back 10

All Division 1, 2 & 3 Divisional Bus Feeder Breakers have the capability to be controlled from its respective units (RSP) (NOT D14 or D24). When the Normal/ Emerg. Switches at the RSP are in EMER, interlocks associated with the MCR handswitches are defeated and the logic uses RSP handswitches.

Front 11

D11 Divisional Bus (6)

Back 11

0A RHRSW Pump
1A RHR Pump
1A Core Spray Pump
0A ESW Pump
1A TEECE Fan
D114 Safeguard Load Center Transformer

Front 12

D21 Divisional Bus (6)

Back 12

0C RHRSW Pump
2A RHR Pump
2A Core Spray Pump
2A TEECE Fan
2A Drywell Chiller
D214 Safeguard LC. Transformer

Front 13

D12 Divisional Bus (5)

Back 13

0B RHRSW Pump
1B RHR Pump
1B Core Spray Pump
0B ESW Pump
1B TEECE Fan
D124 Safeguard Load Center Transformer

Front 14

D22 Divisional Bus (6)

Back 14

0D RHRSW Pump
2B RHR Pump
2B Core Spray Pump
2B Drywell Chiller
2B TEECE Fan
D224 Safeguard L.C. Transformer

Front 15

D13 Divisional Bus (7)

Back 15

1A CRD Pump
1C RHR Pump
1C Core Spray Pump
1A Drywell Chiller
0A Control Room Chiller
D134 Safeguard Load Center Transformer
0C ESW Pump ** when relocated from D23**

Front 16

D23 Divisional Bus (5)

Back 16

2A CRD Pump
2C RHR Pump
2C Core Spray Pump
0C ESW Pump
D234 Safeguard L.C. Transformer

Front 17

D14 Divisional Bus (7)

Back 17

1B CRD Pump
1D RHR Pump
1D Core Spray Pump
1B Drywell Chiller
0B Control Room Chiller
D144 Safeguard Load Center Transformer
0D ESW Pump *** when relocated from D24**

Front 18

D24 Divisional Bus (5)

Back 18

2B CRD Pump
2D RHR Pump
2D Core Spray Pump
0D ESW Pump
D244 Safeguard L.C. Transformer

Front 19

101 Safeguard Bus
Loads

Back 19

D11, D13, D22, D24

Front 20

102 Safeguard Bus
Loads

Back 20

D12, D14, D21, D23

Front 21

Third Offsite Source
Supply, Loads, & how it is aligned

Back 21

13.6 KV power supplied by 66KV substation

Can be connected to 101 or 201 transformers

To aligned the normal transformer supply cables must be disconnected and the alternate source cables connected at the transformer and the alternate source breaker in the 20 station aux bus switchgear room closed in.

Front 22

4.16 KV Breaker Anti-Pump Circuitry

Back 22

Protects large breakers from rapid cycling and could possibly prevent breaker closure

once a breaker is closed the anti pump relay willl energize for 2 seconds to allow the spring to recharage. When energized an auto close singal will not allow the breaker to close.

Significant if
T=0 - D/G breaker manually close
T=0 + - LOCA singal generated
T=0 ++ D/G breaker trips on LOCA signal
T=0 +++ - LOOP - Offsite source breaker trips
T=t1 - D/G breaker recieves a close signal from bus undervoltage relay
if t1< 2 secs then the close signal will be locked out by the anti-pump relay
Operator will have to take switch to TRIP and let it return to NORMAL to obtain auto closure

or

t=0 - a LPCI RHR pump is started
t=0+ - Loss of power D*3
t=0++ - RHR pump trips on undervoltage
t=0+++ - LOCA signal
t=t1 - alternate source breaker closes in - if t1< 2 secs then the close signal will be locked out by the anti-pump relay

Front 23

Auto Closure of a Safeguard L.C. Transformer Breaker

Back 23

(need all of the following:)

1) breaker in connected posistion
2) assoicated 4KV bus lockout relay resets
3) breaker control switch to CLOSE

Front 24

Manual Closure of a Safeguard L.C. Transformer Breaker

Back 24

(need all of the following:)

1) breaker in connected posistion
2) breaker control switch red flagged
3) LOCA singal
4) assoicated 4 KV bus voltage > 95%
5) 3 second time delay followoing LOCA AND 95% bus voltage

Front 25

Auto Trip of a Safeguard L.C. Transformer Breaker

Back 25

Need ANY of the following:

1) associated 4KV bus lockout
2) transformer phase overcurrent
3) transformer ground overcurrnet
4) LOCA
5) Breaker control switch to 'OPEN'

Front 26

Non safeguard loads that must be manually reenergized after a LOCA

Back 26

CRD pumps
Drywell chillers
RHRSW pumps
D*14-G-D and D*24-G-D MCCs, Y-panels *0Y201 and *0Y202 and various 480V loads
TEECE fan (lock out relay must be reset at 4 kv switch gear)

Front 27

Control power for 4KV buses

Back 27

Safeguard DC supplies relay control power to the 4.16 KV system.

Loss of DC power will not de-energize the 4.16 KV bus, but it will defeat the relay protection and breaker operation.

Front 28

Div I DC Loads

Back 28

- Division I
- Div I (250 VDC)
- 1DA: RCIC MOV's, RPS A UPS
- Div I (125 VDC)
- 1PPA-1: RCIC Logic, ADS, CS, RHR, Steam flooding dampers, RSP
- 1PPA-2: D11 D/G logic
- 1PPA-3: RRCS, RSP

Front 29

Div II DC Loads

Back 29

- Division II
- Div II (250 VDC)
- 1DB-1: HPCI MOV's,
- 1DB-2: HPCI MOV's, RPS B UPS
- Div II (125 VDC)
- 1PPB-1: HPCI Logic, CS, RHR, Steam flooding dampers, RRCS
- 1PPB-2: D12 D/G logic
- 1PPB-3:

Front 30

Div III DC Loads

Back 30

- Division III
- Div III (125 VDC)
- 1PPC-1: RCIC INBD isolation valves, ADS, CS, RHR, Steam flooding dampers
- 1PPC-2: D13 D/G logic
- 1PPC-3: RSP

Front 31

Div IV DC Loads

Back 31

- Division IV
- Div IV (125 VDC)
- 1PPD-1: HPCI INBRD isolation valves, CS, RHR
- 1PPD-2: D14 D/G logic
- 1PPD-3: Steam flooding dampers

Front 32

Battery and cell bank consturction and chargers

Back 32

125 VDC = 60 cells (1 Battery) (1 charger)
250 VDC = 120 cells (2 Batteries)* (2 chargers)
Each 60 cell bank has one 125VDC charger (125.2VDC)* (FLOAT – normal trickle current, EQUALIZE = recharge)
(Note: For Div 1 and 2 SG 250 VDC both chargers must be operable. If one is inop, all 250 V loads and ½ of the 125 V loads are lost.)
Each Division has a fuse box and distribution panels.
*except 250 VDC NonSG, which is 1 battery of 120 cells and has one 250 VDC charger.

Front 33

Battery Ratings

Back 33

Div 3 and 4 - 250 amp-hours
Div 1 and 2 - 1500 amp-hours
non safeguard 125/250 - 1500 amp-hours
non safeguard 250 - 1200 amp-hours

Front 34

DC MCCs

Back 34

three safeguard 250 MCCs per unit
Div 1 - one power to RICI
Div 2 - two power to HPCI and RPS A and B inverters

Front 35

Div I & 2 fuse panels

Back 35

Each 125/250 VDC fuse box has three bus bars. For these systems that use 125 and 250 VDC, one bar connects to battery positive, one to battery negative, and the third to the non-fused neutral center tap. This way, 125 VDC is available from neutral to either positive or negative, and 250 VDC is taken from battery positive to negative.

Front 36

Div 3 & 4 fuse panels

Back 36

On 125 VDC systems (Div 3 and 4), only two bus bars are present. This is also true for the 250 VDC EBOP. Only positive and negative bars are fused.

Front 37

power supplies for Emergency Lighting. -

Back 37

*PP01, *PP02, *PP03, *PP04

Front 38

Loss of Div 1 DC (9)

Back 38

1) RCIC is INOP due to loss of power to logic and MOVs. Outboard isolation is INOP.
2) RE and RF isolates.
3) A RPS transfers to Alternate (AC) (AY160)
4) Div 1 RRCS and ADS is INOP. Non-ADS SRVs will only open on pressure. ADS SRVs can still be opened by energizing the Div. 3 solenoids using the AER individual key switches, or by the Div. 3 logic in auto, or by arming and depressing the Div. 3 ADS MAN INIT pushbuttons in the MCR, provided the correct ECCS pumps are running (SRV lights wont work)
5) Control of the 4KV breakers for the corresponding bus is lost. The bus remains energized.
6). The corresponding RHR loop is INOP.
7) The corresponding CS pump is INOP. and entire loop unable to inject, since Div 1 and 2 logic control Core Spray injection valves.
8). MCR HVAC partially isolates. Procedures direct that the operators complete the isolation.
9) The corresponding diesel generator is INOP.

Front 39

Loss of Div II DC (9)

Back 39

1) HPCI is INOP due to loss of power to logic and MOVs. Outboard isolation is INOP
The loss of Div 2 Safeguard DC is the single failure of greatest impact during a DBA LOCA per chapter 15 of the UFSAR
2) RE and RF isolates.
3) B RPS transfers to alternate (AC)
4) Div 2 RRCS is INOP.
5) Control of the 4KV breakers for the corresponding bus is lost. The bus remains energized.
6). The corresponding RHR loop is INOP.
7) The corresponding CS pump is INOP. and entire loop unable to inject, since Div 1 and 2 logic control Core Spray injection valves.
8). MCR HVAC partially isolates. Procedures direct that the operators complete the isolation.
9) The corresponding diesel generator is INOP.

Front 40

Loss of Div III DC (8)

Back 40

1) Loss of power to RCIC inboard isolation logic. RCIC is still operable, but LCO 3.6.3 specifies the system be isolated within 4 hours.
2) Div 3 ADS logic is INOP.
3) 10Y201 supply breaker opens.
4) Control of the 4KV breakers for the corresponding bus is lost. The bus remains energized.
5). The corresponding RHR loop is INOP.
6) The corresponding CS pump is INOP.
7). MCR HVAC partially isolates. Procedures direct that the operators complete the isolation.
8) The corresponding diesel generator is INOP.

Front 41

Loss of Div III DC (7)

Back 41

1) Loss of power to HPCI inboard isolation logic. HPCI is still operable, but like RCIC, LCO 3.6.3 requires isolating HPCI within 4 hours.
2) 10Y202 supply breaker opens.
3) Control of the 4KV breakers for the corresponding bus is lost. The bus remains energized.
4). The corresponding RHR loop is INOP.
5) The corresponding CS pump is INOP.
6). MCR HVAC partially isolates. Procedures direct that the operators complete the isolation.
7) The corresponding diesel generator is INOP.

Front 42

Loss of non safeguard DC (6)

Back 42

a. Loss of control power for 13.2KV breakers, (*PP01, *PP04). Without control power, the breakers can only be operated at the cubicle manually.
b. Loss of APRM inverter power (*PP01, *PP02).
c. instrumentation as necessary). Loss of various annunciators. Each of the 4 panels (*PP01, 02, 03, 04) provides some MCR annunciator power (see ON-122 for specifics).
d. Loss of Emergency Lighting (Supplied by *PP01, 02, 03, 04).
e. Loss of Emergency Lube Oil Pumps for RFPs and Recirc MGs. Loss of power to Recirc MG ELOPs will not trip the Recirc MG, but will prevent starting. (The lube oil pressure switch providing the start permissive is powered from the pump feed.)
f. ESOP & EBOP will not protect the Main Turbine on loss of AC power if the ESOP/EBOP 250 VDC Bus is deengerized.

Front 43

Ground Detection:

Back 43

1) Safeguard – Passive detection (light bulbs;1 'A' & 2 'B' bulbs)
a. No ground – 3 dim bulbs
b. Positive ground – 3 bright bulbs
c. Neutral ground – 'A' light out, 'B' lights bright (2)
d. Negative ground – 'B' lights (2) out, 'A' light bright
2) Non-Safeguard – Active ground detection
a. Small AC signal injected onto DC bus
b. Measures AC current when AC signal has path to ground
c. Alarms at 20kOhms, resets at 26kOhms

Front 44

*AY160 Loads (9)

Back 44

- Inboard Valve Relay Panel (Bkr #1)
- IRM/SRM (RAD Monitor Inst Pnl A) (Bkr #2)
- APRM UPS Inverter *A(Bkr #3)
- Process Radiation Monitoring Vert Bd (Bkr #4)
- RWCU and Recirc Console *0C602 (Bkr #5)
- Area/Process Radiation Recorders Vert Bd (Bkr #7, #10)
- Area/Process Radiation Inst Bd (Bkr #9)
- Turbine EHC (Bkr #14)
- RPS Trip System "A" (Bkr #13)

Front 45

*BY160 Loads (8)

Back 45

Outboard Valve Relay Panel (Bkr #1)
- IRM/SRM (RAD Monitor Inst Pnl B) (Bkr #2)
- APRM UPS Inverter *B (Bkr #3)
- Process Radiation Monitoring Vert Bd (Bkr #4)
- Reactor Control and Feedwater Console and APRM ODAs (Bkr #5)
- Area/Process Radiation Recorders Vert Bd
- (Bkr #7)
- Area/Process Rad Monitoring Inst Bd (Bkr #9)
RPS Trip System "B" (Bkr #13)

Front 46

*AY185 Loads (2)

Back 46

1) Power Range Monitoring Cabinet Bus A
2) Safety/Relief Valve Position Indication

Front 47

*BY185 Loads (3)

Back 47

1) Power Range Monitoring Cabinet Bus B
2) Control Rod Position Information Cabinet
3) Reactor Control and Feedwater Console

Front 48

480 VAC Safeguard
Undervoltage interlock

Back 48

1) Load Center Transformer Breakers (4.16KV) remain closed on undervoltage
2) All Load Center MCC Feeder Breakers (480 VAC) remain closed with the following exceptions:
a) D*14-G-D and D*24-G-D NON-Safeguard MCC feeder breakers
b) These breakers trip at <60% of rated voltage and automatically re-close 5 seconds after voltage is restored >80%

Front 49

480 VAC Safeguard
LOCA with offsite power interlock

Back 49

1) All Load Center Transformer Breakers trip and then re-close after a three (3) second time delay
2) D*14-G-D and D*24-G-D MCC Feeder Breakers trip and will not auto re-close
3) Other safeguard MCCs will re-energize when LC Transformer Breakers close
4) Non-Safeguard 480 VAC loads powered from Safeguard 480 VAC will be tripped by one of the following methods:
a) Most Non-Safeguard loads are tripped by energizing 125 VDC shunt trip coils internal to the molded case circuit breaker at the MCC. Power for the shunt trip coils is from respective division of Safeguard DC.
5) Other Non-Safeguard loads powered from Safeguard 480 VAC are tripped through their control logic

Front 50

480 VAC Safeguard
LOCA with LOOP Interlock

Back 50

1) All LC transformer breakers open and then re-close three (3) seconds after 4.16 KV bus voltage restored to 95% of rated
2) D*14-G-D and D*24-G-D trip and will not auto re-close
3) LC Buses and MCCs de-energize
4) LC's and MCCs will re-energize when LC transformer breakers close
5) Shunt tripped breakers on safeguard MCCs must be manually reset

Front 51

480 VAC Non-Safeguard
Load Center Bus and Tie Breaker Interlock

Back 51

1) If both Bus Breakers are closed, the Tie Breaker cannot be closed
2) Tie Breaker can only be closed if one of the Bus Breakers is open. To cross tie the buses without losing power to bus loads, the Tie Breaker control switch must be held in the CLOSE position while one of the Bus Breaker control switches is placed in TRIP.
3) If one Bus Breaker and the Tie Breaker are closed, closing the second Bus Breaker will trip the Tie Breaker
4) Interlocks prevent paralleling the Unit Aux Buses