TRB Assessment Questions and Answers Flashcards

A structured vocabulary flashcard set covering marine electrical systems, safety devices, engine troubleshooting, regulatory standards, and operational procedures based on the TRB Assessment transcript.

Dead front switch

An electrical switch or panel with no exposed live parts on the front, completely enclosed for safe operation without risk of electrocution.

Megger testing

A method used to measure the insulation resistance of electrical equipment and wiring in megaohms by applying high DC voltage between conductor and insulation.

Earth fault

A condition occurring when a phase conductor comes into contact with the earth.

Neutral Earthing Resistor (NER)

A resistor installed between neutral and earth in high voltage systems that limits fault current, which is then detected by a current transformer (CT).

Sectional testing

The procedure of splitting electrical circuits into parts to locate faults when low insulation resistance is detected.

Afterburning

A diesel engine fault indicated by high exhaust temperature and knocking, caused by unburnt fuel in the exhaust due to injector issues and carbon deposits.

Early injection

An engine fault detected by hard starting and a knocking sound, caused by faulty injection timing and worn cams.

Choked fuel nozzle

An engine fault leading to uneven combustion and misfiring, caused by dirt and fuel impurities.

Worn piston rings

An engine condition causing blow down, low compression, and high oil consumption, resulting from prolonged use or poor lubrication.

Under cooling (scavenge air)

A condition where scavenge air temperature is excessively low, leading to water condensation, cylinder corrosion, and poor combustion.

Scavenge fire

A fire in the scavenge space detected by high exhaust temperature, smoke or flame from scavenge drains, and alarms from temperature sensors in the scavenge belt.

Oil low pressure cut-out

A compressor safety mechanism tested by closing the oil supply valve slightly or adjusting the differential setting to ensure the compressor trips when oil pressure drops below a safe limit.

Modulating control

A boiler burner control method where steam pressure is kept constantly stable without big fluctuations by automatically adjusting burner flame size to match steam demand.

MEPC.107(49)

An IMO resolution adopted by the Marine Environment Protection Committee providing technical guidelines, approval specifications, and testing procedures for OWS and oil content meters under MARPOL Annex I.

Emergency bilge suction

A direct suction line connected to the main sea water cooling pumps from bilge wells to provide emergency drainage during flooding, bypassing the normal bilge pumping system.

Soft starters

Devices used to limit inrush current during motor startup, reducing electrical stress and mechanical shock to driven equipment.

Generator Speed Formula

$$\text{SPEED (RPM)} = \frac{120 \times \text{FREQUENCY}}{\text{NO. of Poles}}$$

Engine Order Telegraph (EOT)

A communication device used to transmit engine commands from the bridge to the engine control room or directly to the engine.

Wrong way alarm

A safety alarm on the engine telegraph or propulsion control system triggered when there is a mismatch between the bridge telegraph order and the actual movement direction of the engine.

Reverse power relay

A generator safety device that trips the circuit breaker to prevent the generator from motoring.

Zone fault

An indication on a fire detection control panel showing that the system has lost communication or detected a malfunction in one of its defined zones.

Locked-in alarm

A safety alarm installed inside cold rooms/fridge spaces enabling a trapped person to alert bridge or duty personnel.

Bump clearance

The small clearance between the piston crown and cylinder head at Top Dead Center (TDC) in an air compressor, measured using soft lead wire or solder.

Bursting disc

A safety device fitted on air compressor intercoolers that ruptures safely to the atmosphere during tube leaks to release overpressure.

Sliding bowl purifier

A self-cleaning purifier where hydraulic pressure moves the bowl axially during sludge discharge to open discharge ports.

Mechanical seal

A device replacing stuffing box packing that utilizes rotating and stationary faces maintained in contact by a spring and liquid film to prevent shaft leakage.

First start arrangement

A starting air system configuration maintaining an isolated reserved air bottle to start a generator and restore main power after a total blackout.

Right-hand search

A systematic search procedure in dark or smoke-filled compartments where firefighters keep their right hand on the bulkhead to ensure complete coverage and orientation.

EPIRB

Emergency Position Indicating Radio Beacon; a safety device that automatically transmits a satellite distress signal with vessel identification and location when activated or submerged.

S-VDR

Simplified Voyage Data Recorder; a device that continuously records navigational data, bridge audio, radar images, and communications to assist in accident investigations.