Abnormal Operation

Question 1

while operating, a large 6,9 motor trips, what action(s) should you take?

Answer 1

-do not attempt a restart of the equipment until the reason for the trip can be determined. start standby equipment or adjust unit output as necessary until the reason for the trip is known and rectified or instructed to attempt a restart by Production or Plant Leader

Question 2

what are the indications of a condenser tube leak?

Answer 2

-an increase in condensate conductivity isolated to one condenser waterbox

Question 3

what would you do?

Answer 3

• send an operator to verify analyzer is operating correctly. (flow, sample pump running, filters clean, etc.)
• check for an increase in sodium and line the sodium analyzer up to that waterbox
• if condition is real, notify the Production Leader
• operate unit according to action limits

Question 4

What are the indications of a boiler tube leak?

Answer 4

• an unusual gap in the indicated feed water and steam flow.
• running out of feed pump
• dropping drum level
• extinguished fired (in extreme cases on lower water wall leaks)
• more than the normal number of condenser make up sprays open
• higher than normal drop in the condensate storage tank

Question 5

What will cause a master burner (fuel) trip?

Answer 5

• drum level high or low (both ends of drum and with greater than 10% fuel flow)
• furnace pressure
• loss of fans
• loss of last burner
• manual push button
• loss of combustion control power
• delayed light off
• low instrument air
• reheat protection

Question 6

What if the Burner Tip Test fails?

Answer 6

• all burner must be checked for leakage into the furnace

Question 7

What would you do if you got a master burner trip at full load?

Answer 7

• notify Production Leader
• at appropriate load transfer to start up power
• at appropriate load transfer controls to manual & open one generator breaker
• lower load to 0 MW
• open second generator breaker
• open field breaker
• trip turbine
• purge the boiler
• once the unit is stable, notify system operation and FPDC

Question 8

What will cause a turbine trio (with parameters)?

Answer 8

• low vacuum 20” Hg
• high exhaust hood temperature 2 of 3 probe logic = or >250 degrees F
• low lube oil at lasting bearing 6 psi
• overspeed 110%
• thrust bearing wear (75 psi)
• ovation graphic trip button
• BTG board trip push handle
• front standard trip push button
• Generator lockout

Question 9

Name 6 things that will cause a full generator lock out.

Answer 9

• loss of field
• generator ground
• generator differential
• negative sequence
• turbine trip
• transformer (main or aux.) differential
• transformer (main or aux.) fault pressure
• system fault

Question 10

What two generator trips will only open the generator breakers?

Answer 10

• underfrequency

- No-load/anti-motoring