Тест состоит из 80 случайных вопросов.
Всего вопросов по данной теме: 118
In which of the following automated control processes will the time constant be of minor importance?
The pyrotechnics used to transmit visual signals to other vessels, boats or aircrafts are of the following type:
All of the below mentioned.
Which of the options given is likely to be the reason for a drop in the charge air manifold pressure of a diesel engine operating with an exhaust gas turbocharger?
Insufficient cooling of the charge air.
Engine room exhaust fans stopped.
Exhaust gas boiler fouled.
When selecting switchgear to work with High Voltage it is important to use an appropriate arcing medium. What is meant by arcing medium?
The gas, liquid or vapor, which will minimize creation of an electric arc as contacts open.
Equipment, which communicates information about the arcing.
A material, which assists a welding process.
When carrying out repair or maintenance tasks involving hot work a hot work permit must be issued. Select the correct option from those given which completes the following statement. The permit for hot work:
Should only cover specific hot work tasks, be valid for a specified time period and be issued by the person carrying out the work.
Should only cover specific hot work tasks and be valid for a specified time period.
Is valid for completion of the specific hot work tasks irrespective of the time taken.
What type of dynamic forces may cause indent in plating on forecastle deck and main deck in way of pillars inside forecastle?
Pressure forces caused by green water on deck.
Impact pressure forces in way of abrupt or flared bow.
Forces created by waves on the forecastle.
Slamming in way of flat bottom forward of light draught.
When starting air is applied to a diesel engine the engine fails to turn over but is seen to oscillate back and forth. What is the most likely cause of this problem?
One or more cylinder air start valves are stuck open.
Starting air pressure is too low.
An interlock is blocking the air to the starting air distributor.
The automatic valve has failed to open.
What should be the healthy continuity resistance of a 220 V, 2,2 kW, 10 A heating element, when checked near to it’s rated operating temperature?
A cable has a resistance of 100 milli-ohms. It supplies a 300 A load over a distance of 100 meters. What is the voltage drop along it’s length?
The majority of conventions adopted under the auspices of IMO fall into which of the three main categories?
Maritime Safety, Prevention of Marine pollution, Liability and compensation.
Maritime Safety, STCW, Maritime Security.
There are no conventions that fall under IMO.
This figure shows a transformer, with two windings, N(1) = 2 000 and N(2) = 1 000 turns, on a common magnetic circuit. Assume that there is no energy loss in the transformer itself. Calculate the current I(2) when the current I(1) = 2 A.
When performing electrical testing of a three phase motor, insulation resistance measurements may be influenced by which of the following?
Temperature, humidity and surface contamination.
Humidity, frequency and dampness.
Humidity, pressure and surface contamination.
Between 0,1 micro Ohm and 1,0 micro Ohm.
What is the maximum current that a 15 Volt, 3 Watt Zenerdiode can handle without damage?
Why is an automatic slow turning feature included in the start air system of many large 2 stroke diesel engines?
To avoid damage during start of the engine in case water or other liquid has gathered in the cylinders during an extended stop.
To reduce the start air consumption during start up of the engine.
To check that all indicator cocks are closed before starting engine.
To fill the cylinders with sufficient fresh air to ensure a safe start of the engine.
In the context of an automated process control system, what is understood by the expression Master Controller?
The primary controller in a cascade control system.
The captain’s controller.
State of the art controller.
The best possible control system.
When measuring viscosity with a restricted flow viscometer, the preferred sensing device is:
What is the advantage of a transmitter with a narrow measurement range?
Do not need any calibration.
Better linearity and increased accuracy.
What should be the healthy continuity resistance of a 220 V, 2,2 kW, 10 A heating element, when checked near to it’s rated operating temperature?
A galley hot plate uses a Nichrome/Magnesium Oxide heating element, and is to be tested before being put into service for the first time. An insulation resistance test yields a reading of 0,3 M Ohm. Which action should be taken?
Put the element into service.
Wash the element in a degreaser agent. Then retest, and if ok put it into service.
Apply reduced voltage to the element for a few minutes. Then retest, and if ok put into service.
Power is available at a three-phase motor starter, but nothing happens (at starter or motor) when the start button is operated. Which of the following is a likely cause?
Open circuit in one of the motor cables.
Faulty overcurrent relay.
A two step controller (open/close) has failed and the only available spare controller is a P+I controller. Select, from the options given, how the P+I controller could be set up to achieve approximate two step control.
Set the proportional band to maximum width and the integral action to minimum (repeats per minute).
Set the proportional band to minimum width and the integral action to minimum (repeats per minute).
Set the proportional band to minimum width and the integral action to maximum (repeats per minute).
Set the proportional band to maximum width and the integral action to maximum (repeats per minute).
The fuel tank contents gauges onboard a vessel are of the air bubble and bell type. The gauges are calibrated for a different fuel type to the actual fuel in the tanks. When correcting the actual contents of the tanks from the gauge readings which of the parameters given in the options is the most important?
In case of a pollution in US waters, who shall notify the cleaning up contractor (OPA-90)?
Sometimes an early warning of failure in High Voltage switchboards may be an unpleasant smell. If the switchboard uses gas circuit breakers, which of the following may indicate a potential problem?
The temperature control for a hot water system is very erratic with the temperature gradually rising and then suddenly falling and vice versa even though system demand is fairly constant. Which of the options given is the most likely cause of this problem?
Control valve gland is over tightened.
Controller integral action reset time is too fast.
Control valve actuator diaphragm is ruptured.
Control air pressure supply is too low.
What does ISM stand for?
The International Management Code for the Safe Operation of Ships and for Pollution Prevention.
International Ship Measurement and Pollution Control.
International Safe Manning Certification.
Internal Ship Safety Management.
A thermistor, which provides feedback for a thermal control system, is suspected to have failed. Assuming there is no available replacement, which of the following methods may be used to prove it has failed?
Disconnect the thermocouple lead from the controller, and replace it with a mA source.
Connect a mA source in parallel with the thermocouple connections.
Connect a mV source in parallel with the thermocouple connections.
Disconnect the thermocouple lead from the controller, and replace it with a mV source.
The coil of a 12 V, 120 mA DC relay must be connected across a 24 V supply. What action should be taken?
Install a 100 Ohm resistor in parallel with the coil.
Install a 100 k Ohm resistor in parallel with the coil.
Install a 100 k Ohm resistor in series with the coil.
Install a 100 Ohm resistor in series with the coil.
When starting three phase induction motors there is sometimes a need to use a star-delta starter. A star-delta starter exhibits the following characteristics while connected in a star.
Reduced current and increased voltage.
Reduced current and reduced torque.
Increased current and power.
Reduced current and increased speed.
How can the pressure be regulated during start up of a positive displacement pump such as a gear pump?
Adjustment of the pressure relief valve to recirculate part of the flow.
Positive displacement pumps operate at constant pressure and cannot be regulated.
By throttling the discharge valve.
By throttling the suction valve.
A ship’s electrical system operates at 60 Hz, but when connected to shore supply it is supplied with 50 Hz. Which of the following would you expect?
Electric motors will run at reduced speed, and will tend to overheat.
Earth faults are more likely.
Electric motors will run at increased speed and will tend to overheat.
Generators are more sensitive to reverse power faults.
How does the maximum oil film pressure in a white metal journal bearing operating under full fluid film conditions compare with the pressure of the lubricating oil supply system?
The pressure is greater than the pressure in the lubricating system and varies with the journal load.
The pressure is the same as the pressure in the lubricating system regardless of the journal load.
The pressure is greater than the pressure in the lubrication and is constant regardless of the journal load.
The pressure is less than the pressure in the lubricating system and varies with the journal load.
Which is the preferred method for starting an air conditioning refrigeration compressor which has been shut down for a period of time?
Start with suction valve throttled in to minimise risk of drawing liquid refrigerant into the compressor.
Start with all system valves fully opened.
Start and stop repeatedly until suction pressure and oil pressure are normal.
Start with the discharge valve throttled in to prevent excess condenser pressure.
In case of pollution in US waters, do you always have to notify the National Response Center (OPA-90)?
Yes, within thirty (30) minutes.
Yes, within three (3) days.
No, not if the local US State Authority is correctly notified.
No, only the shipowner can notify NRC.
Low voltage ships tend to have insulated neutral systems. What is the reason for this?
In the event of an earth fault vital equipment will not trip.
It’s easier to detect faults.
If the neutral is not insulated, then it may short to other conductors.
It’s more effective than insulating the live conductor.
When work must be done on High Voltage equipment, it is vital that the equipment is earthed (grounded) after isolation procedures have been carried out. Why is this?
To provide a reference point, and so ensure accuracy of any test results.
To ensure that it is dead, even if there was a flaw in the isolation procedure.
To ensure that no energy remains in the system, and that it cannot be recharged by external influences.
To ensure that the equipment does not overheat due to currents circulating through earth (ground).
How will continuous low load operation influence the time between overhauls, tbo, for the cylinder covers and associated valves of a 4-stroke diesel engine?
Reduce the time between overhauls due to increasing fouling.
Increase the time between overhauls since the engine is not working as hard.
Increase the time between overhauls since fuel injectors work better at low load so combustion will be improved and the maintenance will be reduced.
Continuity testing of a delta connected three phase induction motor yields the following results; U-V = 3 ohms, V-W = 3 ohms, W-U = 6 ohms. Which of the following is the likely condition?
Open circuit winding between W and U.
Partial fault between W and U.
Short circuit between V and Earth.
Short circuit between W and U.
Some automated control systems use a master controller and a slave controller. What is the meaning of “remote mode” related to a slave controller?
The slave controller can be turned by a hand carried remote controller.
The slave controller can be in any mode of operation.
The slave controller receives the set-point from the output signal of the master controller.
The slave controller can be turned from the engine control room.
Why shall a duly qualified officer supervise any potential polluting operation?
To inform the authorities.
The torsion meter for the main propeller shaft is reading high. The torque is sensed using the angle of twist principle with two clamp rings attached to the shaft at a fixed distance, with stationary proximity switches for measuring the angle of twist and also shaft speed fixed to a rigid stool. What is the most likely cause of the high reading?
Circumferential slip of the after clamp ring in the opposite direction to shaft rotation.
Axial slip of one of the clamp rings to bring them closer together.
Axial slip of one of the clamp rings to move them further apart.
The turbocharger on a diesel engine is surging. Which one of the following options would be the most likely cause?
Dirty scavenging air cooler on the air side.
Dirty rotor blades and nozzle ring.
The lubrication oil pump is malfunctioning.
Worn out bearings on the turbocharger.
The charge air pressure supplied to a diesel engine, which is normally 2,0 bar, is reduced to 1,5 bar. What will be the likely effect on the engine operation?
The performance of the engine will be reduced noticeably.
The performance of the engine will be similar to normal conditions.
The turbochargers cooling water flow will increase.
The cylinder cooling water flow will increase.
In tanker operations, there will be some areas and zones where flammable or explosive vapour, gas, or dust may be expected. Such areas are classified as hazardous. What is meant by hazardous area Zone 1?
Flammable mixture is continuously present or present for long periods.
Flammable mixture is not continuously present, but will be present during normal operations.
Flammable mixture is not present at all times.
Flammable mixture would not normally be present or it would be present for a short period only.
What is the best method for ensuring that the cylinder powers of a high speed diesel engine, fitted with a monoblock multi-cylinder fuel pump, are correctly balanced?
Have the fuel pump phased and calibrated in a test workshop.
Check the exhaust temperatures on each cylinder to see if they are equal.
Measure the maximum pressure of each cylinder to check that they are equal.
Take a set of indicator cards using a mechanical indicator and calculate the cylinder powers.
Oil analysis results for a sample of diesel engine lubricating oil show a high level of tin. What could be the possible cause?
Debris from damage to a white metal bearing.
Debris from damage to a rolling contact bearing.
Cylinder oil contamination of the lubricating oil system.
Debris from fretting between bearing housing parts.
The fuel consumption for the main diesel engine has gradually increased over a period of a few months. All system pressures and temperatures appear normal. From the options given, choose the one which is the most likely cause of this:
Sea water temperature changing.
A draw card obtained from a cylinder of a large 2 stroke diesel engine shows that both cylinder compression and maximum pressures are low. Cards from other cylinders indicate normal operation. What is the likely cause of this problem?
Faulty cylinder component (piston rings, liner, etc.).
Excessive cooling of the charge air.
Faulty high pressure fuel pump.
What kind of electrolyte is used for Nickel-iron batteries?
Solution of sodium and water.
Solution of zinc-carbon and water.
Solution of sulphuric acid and water.
Solution of potassium hydroxide (KOH) and water.
When turning a cascade control system, which of the following actions should be done first?
Adjust the slave controller with the master controller in manual mode.
Adjust both controllers at the same time.
Adjust the slave controller with the master controller in auto mode.
Adjust the master controller with the slave controller disabled.
When the cable length exceeds approx. 10 meters we normally have to, in case of a Pt 100, in some way compensate for the cable resistance. Do we also have to do this if we choose to use a T802 temperature sensor?
Depends on temperature to be measured.
Worn piston rings are allowing a small amount of piston blow-by on a 2-stroke main diesel engine cylinder, but due to the circumstances, it is not possible to stop and do a piston overhaul. What is the correct, temporary action to take?
Increase cylinder oil feed rate slightly and monitor the scavenge space drains.
Continue to operate the engine as normal.
Increase cylinder oil feed rate to the maximum.
How can a lead-acid type battery be checked to confirm if it is fully charged or not?
Measure the relative density (specific gravity) of the electrolyte.
Measure the battery voltage.
Measure the level of the electrolyte.
Measure the temperature of the electrolyte.
A 6-Volt DC relay is to be used with a 12-Volt power supply. The relay requires a current of 0,1 Amp. What is the series resistance required?
In terms of automated control systems, what is typical for a continuous control system?
It is possible to predict the control mathematically.
The control valve will always be changing position.
It is not possible to have a stable process.
The output signal is equal to the input signal.
The muster list shall show the duties assigned to the different members of the crew. Which of the given duties necessarily have to be included in the muster list?
Preparation and launching of survival crafts.
Type of fires that can be encountered on board.
Preparation and starting of emergency generator.
What is the purpose of the relief valves fitted to the doors and casing of 2-stroke diesel engine crankcases?
To relieve excess pressure in the crankcase resulting from a crankcase explosion.
To relieve excess pressure in the crankcase resulting from piston rod gland leakage.
To maintain a constant pressure in the crankcase.
The engine turns over normally when starting air is supplied but does not fire even though normal starting rpm is achieved. What could be the probable cause to this?
Air in the fuel oil system.
The lubricating oil temperature is low.
The turbocharger has not run up to normal full speed.
The turning gear interlock has operated.
Two reference points for pressure exist, absolute zero and atmospheric pressure. What are pressures measured relative to absolute zero called:
When considering instrumentation systems, what is the meaning of the expression “dead-band”?
The controller will not react to a process change in this range.
It will take some time before the controller will react to a change.
The controller will enter “sleep mode”.
The controller will not respond to adjustment of set-point.
How is a Safety Management Certificate obtained?
Ship owner has Document of Compliance issued, and vessel is assessed and holds all statutory certificates.
RSS issue SMC with Register.
Vessel is surveyed by MCA and certificate issued.
Ship owner is authorised to carry out internal audits and issue SMC.
A portable oxygen analyser for use onboard ship is of the paramagnetic sensing element type. It is being used to test the atmosphere of a space onboard ship but starts to give erratic readings. There is no obvious indication as to why this is happening. Select from the options given the most likely cause of this problem:
The sampling filter is partially blocked giving rise to wide pressure variations in the sampling chamber.
The battery power is low.
Nitrogen gas is present in the atmosphere.
The sampling filter is blocked preventing gas from entering the sampling camber.
The operating mode of a pyrotechnic signal depends essentially on:
Instructions or diagrams printed on its casing by the manufacturer.
The weather conditions of the moment.
The fact that the user is on board a liferaft, a lifeboat or ship.
A definite standard process.
The cold room temperature is almost at the cut out point in a vapour-compression refrigeration system. What should the refrigerant state be just after the evaporator if the system is correctly set up?
Slightly superheated low pressure gas.
Wet vapour at high pressure.
Sub-cooled liquid at low pressure.
Cold liquid at high pressure.
The main propulsion diesel engine is normally started by direct admission of compressed air. Which one of the following statements is correct?
A heavily leaking starting air valve may cause an explosion in the starting air pipe system.
The starting air admission should continue until the engine has fired.
If the engine does not turn when the starting air is applied the turning gear can be used together with starting air to start the engine.
If the starting air pressure is too low a pressurized oxygen bottle from the welding equipment can be used for an emergency start of the engine.
What principle of measurement are viscosity controllers usually based on?
Measurement of differential pressure.
Measurement of two different temperatures.
Measurement of temperature.
During maintenance work on the main engine a problem arises regarding the lifting of a main component in that the manufacturer’s instructions ado not apply to the engine as fitted and present a hazard. In which of the information/record sources given in the options, is it most important to record the information relating to this anomaly?
ISM procedures in the ship’s safety manual.
Engine room planned maintenance schedule.
Continuity testing of a delta connected three phase induction motor yields the following results: U-V = 3 Ohms, V-W = 3 Ohms, W-U = 6 Ohms. Which of the following is the likely condition?
Short circuit between V and Earth.
Open circuit winding between W and U.
Partial fault between W and U.
Short circuit winding between W and U.
In the context of an automated control system, which controller must be tuned first in a cascade control system?
The secondary controller.
What is the result of an “unusually large metacentric height”?
The vessel will roll slowly or be unstable.
The vessel will have a great bending moment.
The vessel’s tweendeck heights is too high.
The vessel will roll violently.
What should be the healthy continuity resistance of a 220V, 2,2kW, 10A heating element, when checked near to it’s rated operating temperature?
Some diesel engines have alarm and slow down protection in the event of a fire in the scavenge boxes. Choose the option which would be a typical set point for giving a slow down of the engine in the event of a scavenge box fire?
After a couple of hours of operation the failure alarm sounds for a heavier fuel oil purifier which is operating on a timed automatic sludge cycle. Upon investigation the purifier is found to be running slowly and when opened up the casing and sludge outlet is heavily fouled with sludge in contact with the bowl. From the options given what is the most likely cause of this problem?
The heavy fuel is unstable leading to excessive high viscosity sludge formation.
The dirty oil throughput is excessive.
The clutch for the drive shaft is worn and slipping.
The purifier bowl has not closed properly.
What is the correct operation of the slow-turning facility fitted to some large 2-stroke main propulsion diesel engines?
Slow turning should be set to operate automatically prior to engine start when engine has been stopped for 20 to 30 minutes during manoeuvring.
Slow turning should be set to operate automatically every 10 to 15 minutes when the engine is on standby.
Slow turning should be carried out immediately the duty engineer gets notice of standby from the bridge.
Slow turning should be set to operate automatically at finish with engines to allow the engine to cool down evenly.
Why is it necessary to have an effective ballast water management plan which includes provision for changing out ballast in open water rather than discharging ballast in coastal waters?
To avoid the introduction of non-indigenous species of marine life from one area to another.
To keep the ballast water fresh in the ballast tanks during long voyages.
To allow ballast tank inspections to be carried out during ballast passage.
To ensure that ballast tanks are always pressed up during a ballast voyage to avoid free surface effects.
When considering instrumentation systems, what is a typical symptom of a fault with the span of an instrument?
100 % output is accurate, but Zero-point is wrong.
Zero-point and 100 % are correct, but not at mid-range.
Zero-point is accurate, but 100 % input is not giving 100 % output.
A two step controller (open/close) has failed and the only available spare controller is a P+I controller. Select, from the options given, how the P+I controller could be set up to achieve approximate two step control.
Set the proportional band to maximum width and the integral action to minimum (repeats per minute).
Set the proportional band to minimum width and the integral action to maximum (repeats per minute).
Set the proportional band to minimum width and the integral action to minimum (repeats per minute).
The main engine is running steady with an average exhaust gas temperature of approximately 350 °C. What would be a typical alarm/slow down setting for the cylinder exhaust gas temperature deviation from the average?
An indicator card from a cylinder of a slow speed diesel engine shows a high maximum pressure occurring earlier in the cycle than normal with a normal compression pressure. From the options given, which action is most likely to identify the cause of the problem?
Check if the fuel injection pump timing is correct.
Check if the fuel filters are blocked.
Check if the fuel viscosity and temperature are correct.
Check if the fuel injection valve is partly blocked.
A 250 V contactor has been fitted to a 220 V supply. Which of the following symptoms might be observed?
Contactor chattering (vibrating).