1.
When wiring a modern 13 amp square pin electric plug which colour wire is connected to earth?
Correct Answer
C. Yellow/Green
Explanation
The colour wire that is connected to earth when wiring a modern 13 amp square pin electric plug is Yellow/Green.
2.
IF excessive current flows in a circuit which of the following does not automatically isolateElectrical Competence the circuit?
Correct Answer
C. The isolating switch.
Explanation
The isolating switch does not automatically isolate the circuit when excessive current flows. It is designed to manually disconnect the circuit for maintenance or repair purposes, but it does not have the capability to automatically detect and isolate the circuit in the event of excessive current.
3.
Which of the following statements about electrical fuses is true?
Correct Answer
A. Fuses protect circuits and people from excess current automatically.
Explanation
Fuses protect circuits and people from excess current automatically. Fuses are designed to break the circuit when there is an excessive flow of current, preventing damage to the circuit and potential harm to people. This is achieved by using a wire or metal strip that melts when the current exceeds a certain level, breaking the circuit and stopping the flow of electricity. Once the fault or excessive current is resolved, the fuse needs to be replaced in order to restore the circuit's functionality and ensure continued protection.
4.
The charge in a lead acid battery can be measured with which of the following?
Correct Answer
A. A hydrometer.
Explanation
A hydrometer is used to measure the specific gravity of the electrolyte in a lead acid battery. The specific gravity is directly related to the state of charge of the battery. By measuring the specific gravity, one can determine the charge level of the battery and whether it needs to be recharged or not. A thermometer measures temperature, which is not directly related to the battery's charge. An ammeter measures current, which can provide information about the battery's performance but not its charge level. Therefore, the correct answer is a hydrometer.
5.
Which of the following would be powered by 440 volts A.C. on a modern ship?
Correct Answer
B. Pumps turned by electric motors.
Explanation
Pumps turned by electric motors would be powered by 440 volts A.C. on a modern ship. This is because pumps require a higher voltage to operate efficiently and effectively. The other options, such as alarm panels, emergency generator starter motors, and accommodation lighting, may require a lower voltage for their operation.
6.
Behind the main switchboard are copper bars carrying electrical current. These are called
Correct Answer
D. Bus bars.
Explanation
Bus bars are copper bars that carry electrical current behind the main switchboard. They provide a low-resistance path for the flow of electricity and help distribute the electrical power to different circuits. Transformers are devices used to change the voltage of electrical energy. Breakers are devices used to protect electrical circuits from overloads or short circuits. Batteries are devices that store electrical energy. Therefore, the correct answer is bus bars.
7.
A valve which is operated by an electric circuit is called a:
Correct Answer
B. Solenoid valve.
Explanation
A valve that is operated by an electric circuit is called a solenoid valve. Solenoid valves use an electromagnetic solenoid coil to control the flow of fluid or gas through the valve. When an electric current is passed through the coil, it creates a magnetic field that opens or closes the valve, allowing or stopping the flow. Solenoid valves are commonly used in various applications, such as irrigation systems, HVAC systems, and industrial processes, where remote control or automation is required.
8.
The instrument used to measure electrical insulation is called:
Correct Answer
A. A megger.
Explanation
A megger is an instrument specifically designed to measure electrical insulation. It is used to determine the resistance between two points in an electrical circuit, which helps to assess the effectiveness of the insulation. A motor meter is not a commonly used term and does not specifically refer to an instrument for measuring electrical insulation. A voltmeter measures voltage, while an ammeter measures current, but neither of these instruments is designed for measuring insulation. Therefore, the correct answer is a megger.
9.
Watts are a measurement of:
Correct Answer
B. Electrical power.
Explanation
Watts are a measurement of electrical power. Power is the rate at which energy is consumed or produced, and it is measured in watts. Watts are used to quantify the amount of electrical power that a device or system can generate or consume. The higher the wattage, the more power the device or system can handle. Therefore, the correct answer is electrical power.
10.
When a fuse is rated 8 A, it means :
Correct Answer
D. It will melt if current exceeds 8 A
Explanation
A fuse is a safety device that is designed to protect electrical circuits from excessive current. When a fuse is rated 8 A, it means that it is designed to safely carry a maximum current of 8 A. If the current exceeds this rating, the fuse will heat up and eventually melt, breaking the circuit and preventing further damage or potential hazards. Therefore, the correct answer is that the fuse will melt if the current exceeds 8 A.
11.
What is the purpose of a Tacho- generator?
Correct Answer
A. To measure revolutions per minute (RPM).
Explanation
A Tacho-generator is a device used to measure the revolutions per minute (RPM) of a rotating shaft. It generates an electrical signal proportional to the rotational speed of the shaft. This information is useful in various applications such as controlling the speed of motors, monitoring the performance of engines, and ensuring the accuracy of machinery. By measuring the RPM, the Tacho-generator helps in maintaining the desired speed and efficiency of the rotating equipment.
12.
Which of the following detectors will you choose for detecting smoke from fire?
Correct Answer
D. Ionization type
Explanation
The ionization type detector is the most suitable choice for detecting smoke from fire. This type of detector works by using a small amount of radioactive material to ionize the air in the detector chamber. When smoke particles enter the chamber, they disrupt the ionization process, triggering an alarm. This type of detector is highly effective at detecting small amounts of smoke and is commonly used in residential and commercial buildings for fire detection and alarm systems.
13.
One of the following statements with regards to Portable equipment is not correct:
Correct Answer
D. Ship’s Bosun is generally asked to inspect portable electrical equipment.
Explanation
Portable electrical equipment is typically inspected by trained personnel, such as electricians or safety officers, who have the necessary knowledge and expertise to ensure its safety and compliance with regulations. The ship's bosun, who is responsible for general maintenance and repairs on the ship, may not have the specific training and knowledge required to inspect electrical equipment. Therefore, it is not correct to say that the ship's bosun is generally asked to inspect portable electrical equipment.
14.
The use of compact fluorescent (CFL) lamps is not permitted in the vicinity of marine safety communications equipment. Because:
Correct Answer
C. There is a radio interference issue with this light as a result Us Coast Guard has banned the use of CFL.
Explanation
The correct answer is that there is a radio interference issue with CFL lamps, leading to the ban by the US Coast Guard. This means that the use of CFL lamps near marine safety communications equipment can disrupt the radio signals, which is why they are not permitted in such areas.
15.
Fast and accurate assessment of Life &Rescue Boat battery condition can be done:
Correct Answer
D. By using shell approved battery load tester
Explanation
Using a shell approved battery load tester is the best method for fast and accurate assessment of Life & Rescue Boat battery condition. This tester is specifically designed for testing batteries and can provide reliable results. Regular testing of battery voltage using a digital multimeter can also be helpful, but it may not give as accurate results as a load tester. Carrying out engine starts each week and checking electrolyte levels are important maintenance practices, but they may not provide a comprehensive assessment of the battery condition.
16.
The electrolyte in a charged lead acid battery consists of water and
Correct Answer
D. SulpHuric acid.
Explanation
The electrolyte in a charged lead acid battery consists of sulphuric acid. Sulphuric acid is commonly used as an electrolyte in lead acid batteries because it is a strong acid that can easily dissociate into ions, allowing for the flow of electric current. It also helps to maintain the proper concentration of ions in the battery, which is essential for its proper functioning. Additionally, sulphuric acid has a high boiling point and low vapor pressure, making it suitable for use in a battery.
17.
Which of the following duties would NOT be served by primary batteries?
Correct Answer
A. Hand torches.
Explanation
Primary batteries are non-rechargeable batteries that provide a one-time use of electrical energy. They are commonly used in devices that require low power and have a long shelf life. Hand torches, or flashlights, require a continuous and reliable source of power, which primary batteries cannot provide. On the other hand, emergency lighting, low voltage systems such as telephones, and emergency generator starting can all be served by primary batteries as they do not require constant power supply. Therefore, hand torches would NOT be served by primary batteries.
18.
What will you do if you are told to operate unknown mechanical equipment?
Correct Answer
B. Seek advice from your superior before attempting to operate it.
Explanation
When faced with operating unknown mechanical equipment, it is important to seek advice from a superior before attempting to operate it. This is because operating unfamiliar machinery without proper guidance can be dangerous and may lead to accidents or damage. Seeking advice from a superior ensures that you have the necessary information and guidance to operate the equipment safely and effectively. It is always better to prioritize safety and seek guidance rather than taking risks with trial and error methods or operating without proper knowledge.
19.
Which group of electrical services are likely to be supplied from an emergency
Correct Answer
A. Steering gear and alarm system
Explanation
The group of electrical services that are likely to be supplied from an emergency source are the steering gear and alarm system. In emergency situations, it is crucial to have a power supply for these systems to ensure the safety and control of the vessel. The steering gear is responsible for controlling the direction of the ship, while the alarm system alerts the crew to any potential dangers or emergencies. Therefore, it is essential to have a reliable emergency power source for these critical systems.
20.
Regular (at least weekly) testing of the emergency generator must be performed to check:
Correct Answer
A. Its readiness to perform as specified.
Explanation
Regular testing of the emergency generator is necessary to ensure that it is ready to perform as specified. This means that it should be able to function properly and provide the necessary power during an emergency situation. Testing helps identify any potential issues or malfunctions that may affect its performance, allowing for necessary repairs or maintenance to be carried out. This ensures that the generator is reliable and can be relied upon in case of an emergency.
21.
What precaution is to be taken when the Engineer on Duty is entering an UMS-mode operated engine room due to an alarm or due to a scheduled routine check?
Correct Answer
C. Switch the UMS selector switch to manual mode and engage the "dead man alarm"
Explanation
When the Engineer on Duty is entering an UMS-mode operated engine room due to an alarm or a scheduled routine check, the precaution that needs to be taken is to switch the UMS selector switch to manual mode and engage the "dead man alarm". This ensures that the engine room is not left unattended and that the alarm system is activated to alert others in case of any emergency. Leaving the UMS selector switch in UMS-mode or switching it to manual mode only may not provide the necessary safety measures in such situations.
22.
Prior to the lunch break, the Engineer on Duty observes that the operating generator set has an output of 90%. With regard to operation of the generator, what is the - most important - assumption(s) for him to check before switching to UMS-mode?
Correct Answer
D. That a secondary auxiliary set is switched to automatic standby mode
Explanation
The most important assumption for the Engineer on Duty to check before switching to UMS-mode is that a secondary auxiliary set is switched to automatic standby mode. This is crucial because in UMS-mode, if the operating generator set fails, the secondary auxiliary set will automatically take over to ensure uninterrupted power supply. Therefore, it is essential to confirm that the secondary auxiliary set is ready and in standby mode before making the switch.
23.
When you make a visit to the emergency diesel generator during your engine room watch, what should you look out for?
Correct Answer
A. Cooling system fresh water level, oil level in sump tank, preheating temperature of cylinders, charging level of batteries, diesel in stand-by mode.
Explanation
During a visit to the emergency diesel generator, it is important to check the cooling system fresh water level, oil level in the sump tank, preheating temperature of cylinders, charging level of batteries, and whether the diesel is in stand-by mode. These checks ensure that the generator is properly maintained and ready for use in case of an emergency.
24.
What are ideal conditions for taking Megger test readings of a motor or alternator?
Correct Answer
C. Hot after stopping.
Explanation
The ideal condition for taking Megger test readings of a motor or alternator is when it is hot after stopping. This is because when the equipment is hot, any insulation breakdown or faults are more likely to be detected. This is because the heat causes the insulation to expand, making any faults more visible. Additionally, taking readings when the equipment is hot allows for a more accurate assessment of the insulation resistance.
25.
If an alternator runs at 900 RPM and delivers AC current at 60 Hz, how many pole pairs has this alternator got?
Correct Answer
C. Four
Explanation
An alternator's speed is directly proportional to the frequency of the AC current it delivers. In this case, the alternator is running at 900 RPM and delivering AC current at 60 Hz. The number of pole pairs in an alternator is equal to the number of magnetic poles divided by 2. The formula to calculate the number of pole pairs is: Pole pairs = RPM / (120 * Frequency). Plugging in the values, we get: Pole pairs = 900 / (120 * 60) = 4. Therefore, the alternator has four pole pairs.
26.
A worker entering the flash protection boundary must be qualified and:
Correct Answer
C. Must be wearing arc flash PPE as appropriate
Explanation
When a worker enters the flash protection boundary, it is crucial that they are qualified and wearing the appropriate arc flash personal protective equipment (PPE). This is because the flash protection boundary is an area where workers are at risk of being exposed to arc flash hazards, which can cause serious injuries or even fatalities. Therefore, wearing the correct arc flash PPE is essential to protect the worker from the thermal energy, intense light, and pressure that can be released during an arc flash event.
27.
NFPA 70E and ASTM F1506 require that an Arc Flash garment be marked on its label: its specific arc protective rating.
Correct Answer
C. It’s specific arc protective rating
Explanation
NFPA 70E and ASTM F1506 require that an Arc Flash garment be marked on its label with its specific arc protective rating. This rating indicates the level of protection the garment provides against arc flash hazards. It helps users select the appropriate garment for their specific work environment and ensures that they are adequately protected. The specific arc protective rating is an important piece of information that must be clearly stated on the garment label to ensure safety and compliance with industry standards.
28.
If the EEO or maintenance person will be working with a de-energized circuit, the arc flash boundary and PPE is not necessary.
Correct Answer
B. How do you know if the equipment is de-energised until you test it, so when testing, arc flash boundary and PPE is required.
Explanation
The explanation provided correctly points out that it is necessary to use arc flash boundary and personal protective equipment (PPE) when working with a de-energized circuit. This is because it is not possible to determine if the equipment is de-energized until it is tested. Therefore, to ensure safety, it is important to follow proper procedures and use appropriate protective measures, such as arc flash boundary and PPE, when working with electrical circuits.
29.
Which statement is correct:-
In addition to a Safety Plan, Training, Signs/Labelling and Arc Flash Boundary assessment and PPE, what else is required:
Correct Answer
D. All the answers are correct.
Explanation
The correct answer is "All the answers are correct." This means that all of the options mentioned (work permit, lockout and tag out program, and tools for safe work on the equipment) are required in addition to a safety plan, training, signs/labelling, arc flash boundary assessment, and PPE.
30.
In what ways are fuses rated?
Correct Answer
D. All
Explanation
Fuses are rated in terms of current, voltage, and time delay. The current rating indicates the maximum amount of current that the fuse can safely handle without blowing. The voltage rating indicates the maximum voltage that the fuse can safely interrupt. The time delay rating indicates the amount of time the fuse can sustain a current higher than its rating without blowing. Therefore, all of these factors are considered when rating fuses.
31.
A circuit breaker is
Correct Answer
D. Acurrent interrupting device.
Explanation
A circuit breaker is a device that interrupts or breaks the flow of current in an electrical circuit. It is designed to protect the circuit from overloads, short circuits, and faults by automatically opening the circuit when abnormal conditions occur. When a fault or abnormal current is detected, the circuit breaker trips and interrupts the flow of electricity, preventing damage to the circuit and equipment. Therefore, the correct answer is "A current interrupting device."
32.
A capacitor start, capacitor run single phase induction motor is basically a
Correct Answer
C. 2 pHase induction motor
Explanation
A capacitor start, capacitor run single phase induction motor is a type of motor that uses two capacitors to start and run the motor. It is called a "single phase" motor because it operates on a single phase AC power supply. The motor has a special winding arrangement that creates a rotating magnetic field, which allows it to start and run smoothly. This type of motor is commonly used in applications where a high starting torque is required, such as in air conditioning units or refrigerators. It is not an AC series motor, DC series motor, or 3 phase induction motor.
33.
Resistivity of a wire depends on
Correct Answer
B. Material
Explanation
The resistivity of a wire depends on the material it is made of. Different materials have different resistivities, which determine how easily or difficultly they allow the flow of electric current. Therefore, the material of the wire is a key factor in determining its resistivity. The length and cross-sectional area of the wire also affect its resistance, but they do not directly determine the resistivity of the wire.
34.
UPS is:
Correct Answer
B. Uninterrupted power supply
Explanation
UPS stands for Uninterrupted Power Supply. It is a device that provides backup power to electrical devices in case of a power outage or fluctuation in the main power supply. It ensures uninterrupted power supply to prevent any disruption or damage to the connected devices.
35.
A power supply which maintains the voltage constant irrespective of ac main fluctuations or load variations is known as
Correct Answer
B. DC regulated power supply
Explanation
A DC regulated power supply is a type of power supply that is designed to maintain a constant voltage output regardless of fluctuations in the AC mains or variations in the load. This ensures a steady and reliable power supply to the connected devices, making it suitable for applications where a stable voltage is required. Unlike a basic DC power supply, which may not have regulation circuitry, a regulated power supply incorporates control mechanisms to adjust the output voltage and keep it constant. Therefore, a DC regulated power supply is the correct answer in this case.
36.
The piece of electrical equipment used for changing a voltage, up or down, is called :
Correct Answer
D. a transformer
Explanation
A transformer is a piece of electrical equipment used for changing a voltage, either stepping it up or stepping it down. It consists of two or more coils of wire wrapped around a core and operates on the principle of electromagnetic induction. When an alternating current passes through the primary coil, it creates a magnetic field which induces a voltage in the secondary coil. This allows for the efficient transmission of electricity at different voltage levels, making it an essential component in power distribution systems.