Question 263Steam Plants - 1st Asst/Chief70% to pass
On a steam turbine vessel with a propeller type, electrically driven, main circulating pump, one suspects condenser tube or inlet tube sheet fouling. Do not consider vacuum variations since they may be due to sea water temperatures. What on-board electrical test instrument can one use to verify condenser fouling?
AI Explanation
The correct answer is B) Amp meter on motor controller leads. Higher than design full load amperage will indicate potential fouling.
The reasoning is that if the condenser tubes or inlet tube sheet become fouled, the restriction to water flow will increase, causing the main circulating pump to work harder to maintain the necessary water flow. This increased work load will result in the main circulating pump motor drawing higher than normal electrical current, which can be detected by monitoring the amperage on the motor controller leads.
The other answer choices are incorrect because: A) Lower than normal amperage would not indicate fouling, C) Voltage variations are not a reliable indicator of condenser fouling, and D) Visually inspecting the condenser requires shutting down the plant, which may not be necessary if the electrical test in B) is performed.
Related Questions
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