A hospital generator undergoes a weekly no-load test run for 30 minutes. Over time, the exhaust stacks start dripping thick black sludge. What maintenance problem has been created, and what strategy fixes it?
Answers
ACavitation; fixed by replacing the coolant pump
BWet stacking; fixed by running the generator under a heavy load bank to burn off unburned fuel
CHarmonic resonance; fixed by adding a line reactor
DBearing wipe; fixed by greasing the alternator
The answer and explanation are in the full bank.
This question is one of 2,831 in the paid banks. Each comes with the correct answer and the reasoning behind it, not just a mark.
Unlock for 5,000 RWFMIFOTRA exam practicealigned to CompTIA (General IT) / BICSI·3 marks·Medium
More Maintenance questions
- A maintenance mechanic is tracing a pipeline issue and looks at a P&ID (Piping and Instrumentation Diagram). They see a circle with the letters "FIC". What does this instrument bubble represent?
- On a one-line electrical diagram, a technician sees a breaker symbol with the number "52" next to it, and a relay symbol with "51". According to ANSI/IEEE standard device numbers, what do these represent?
- A machine stops running. The HMI shows no faults. The tech connects a laptop to the PLC and sees the main sequencer rung is false because a proximity switch input is flickering rapidly. What is the mechanical cause?
- A technician calibrates a 0-100 psig pressure transmitter. They apply exactly 50 psig to the transmitter. The output reads 11.5 mA. The spec requires ±0.5% of span accuracy. Does this pass?
- You are tasked with replacing a variable frequency drive (VFD). You need to know the exact parameters to program into the new drive so it behaves like the old one. Where is the best place to find this information?
- A gearbox exhibits a high-frequency vibration spike surrounded by sidebands spaced at exactly the input shaft running speed. What does this signature specifically diagnose?
- You scan a control panel and find a fuse block that is glowing bright white on the IR camera (extremely hot). The wire leaving the fuse block is cool. The other two phases are normal temperature. What is the issue?
- While reviewing a piping diagram, you see a valve symbol that looks like a bowtie with a line drawn completely through it, forming an "X". What type of valve does this represent?