MFP Turbine Ctrls

Question 1

When are the MFPs forced to speed ctrl?

Answer 1

• Both MS Press xmitters Fail
• Both MFP Hdr # xmitters Fail
• MFP DP Setpoint xmitter Fails
• Other MFP Trip when > 60% Power
• MFP Speed > 5220 (5300) rpm when its forced to speed ctrl

Question 2

What will override MFP Speed Ctrl on U2? Why?

Answer 2

MFP 1st Stage # Limiter to prevent excessive 1st stage pressure

- Will close down on control valves to prevent excessive 1st stage #. (@ 105# first stage # and 5300 rpm)

Question 3

When is MFP ΔP enabled?

Answer 3

• Unit 1MFP Speed > 3650 RPM
  -Unit 2 MFP Speed > 3500 RPM

Question 4

What feeds the Steam Flow input for the DP Control for program DP?

Answer 4

Total Steam Flow selected Channels

Question 5

What transmitters feed the steam pressure portion for DP Control for actual DP?

Answer 5

UPC-102A/B (Bypass Steam header) (Higher of 2)

- FPC-250A/B (6A FW Htr outlet) (Lower of 2)

Question 6

What parameter tells the Main Turbine that power is > 60%?

Answer 6

• Actual Load
  Unit 1 > 626.4 MW
  Unit 2 > 730.2 MW

Question 7

What are the Hardwired (direct) Trips for the MFPs?

Answer 7

Manual
Rx trip
SI
Hi-Hi S/G level at 67%
IOPS (110%)
Thrust Bearing position

Question 8

What are the PLC Trips for the MFPs?

Answer 8

• Overspeed (107%)
• Low Condenser Vacuum ≤ 20.0 (15 for Unit 2) in Hg
• Low Lube Oil press (4#) (5 sec TD)
• Low Suction press (180#) (5 sec TD)
• Low Trip Header Press (800#)

Question 9

At what percent power do we normally use Main Steam for the MFP motive force?

Answer 9

Until ~ 55-60% Power

Question 10

How is MFP DP Calculated?

Answer 10

By using the highest Bypass Hdr Steam Pressure and the lowest FW Pressure

Question 11

What are the inputs to the MFP Speed Control System?

Answer 11

SG Pressure, FP Disch Pressure and TOTAL STEAM FLOW

Question 12

If there is an equipment issue with on of the MFP suction flow transmitter (fails low), what is affected?

Answer 12

Load Sharing and ELO Control