Generator Hydrogen And CO2 Flashcards
How is hydrogen circulation maintained?
Difference in pressure of the generator fans during operation.
What cools the hydrogen that cools the generator?
Two duplex type shell and tube HXs
Where is CO2 purge operations controlled from?
Hydrogen purge station in the 140’ turbine building east side.
Where is the carbon dioxide used in the purging process supplied from?
Cardox unit (vaporizer) in the fire protection system
How is co2 introduced and purged from the generator?
Introduced in the bottome purged through the top.
Where is the air supplied from during the purging of the co2?
From service air via a temporary hose attached to the bulk supply connection.
How is generator hydrogen temperature controlled to a set point?
Gh-tic-7 monitors the hydrogen temp and that signals temp control valve 132.
What physical device ensures that only hydrogen or co2 is supplied?
A single removable spool piece.
What is used to maintain the generator hydrogen pressure to 75psig?
GHN-PCV-10 pressure regulator
How does the dryer moisture remover remove moisture from the hydrogen or gasses entering the generator?
Has an activated alumina drying agent. Flow is driven by the shaft mounted fans in the generator.
What colors do the activated alumina crystals change to once spent?
Pink
Starts out blue.
What purity must hydrogen be maintained at?
90% in air.
What happens if the hydrogen purity drops below 80%?
Generator must be shutdown.
75% is the upper explosive limit.
What device is used to monitor for overheating in a gas cooled generator by detecting thermal decomposition of organic material?
Core monitor
Generator insulation gives off the particles.
What happens when the core monitor has detected a large amount of particles?
Alarm in control room and pyrolysate collector is activated.
Readout of these instruments provided in the control room.
