Answers to CES test about Engine Management Electronics

Welcome to the website where you can find answers for the CES test on the subject «Electrical Electronic & Control». This site will help you as a marine specialist improve your knowledge with the help of open information, where you can find questions as well as answers for them. CES based on practical information and marine specialists experience.

CES tests developed for evaluating seaman basic knowledge by Seagull Company (rebranded as «OTG»), is an evaluating online-tool, used for revealing any professional preparation needed in specific fields of knowledge, defined by STCW.

Version: 6.0.10.
Test type: STCW.
Department: Engine.
Level: Management.
Module: Electrical Electronic & Control.

CES tests have proven themselves as good tools for the selection and recruitment process, as well as advancing the level of knowledge of the current officers and crew. Ocean Technologies Group use various subjects for question creation, which includes:

Crowd and Crisis Management;
Integrated Navigation System (INS);
Ballast water management;
Handling and Stowage;
Vessel operation management and safety;
Marine engineering;
Maintenance and repair, etc.

«Electronics» subject includes theoretical and practical information about safety working with electrical equipment. Knowledge of this information directly shows employee’s competence who holds a relevant post on a vessel. The role of a worker in the machine department involves providing equipment support and requires a solid technical understanding of the equipment’s operation and components. It is important for them to be well-versed in the fundamental principles of each device’s function, as well as capable of diagnosing and resolving malfunctions. To effectively perform tasks related to servicing and repair, it is crucial for the employee to stay up-to-date with the latest updates and advancements in equipment technology. Additionally, having basic communication and collaboration skills is essential for interacting with team members and clients, particularly when providing assistance and consultations.

This page contains answers to Seagull CES (Crew Evaluation System) test about Electrical Electronic & Control, and serve as a database of questions and answers, using which seafarer can prepare to exams for getting certificate of competence, or just to challenge yourself with knowledge in this theme.

Special thanks to JSEC and Mr Animesh from our Telegram channel, without you this test would not exist.

Use the search below to find question.

Amount of questions: 40.

Right answers marked with this sign .

Code: RTXB A 5 V DC source has an internal impedance of 0,2 ohms. When a load of 2,3 ohms is applied what voltage will be measured at the source terminals?

4,6 V.

5,2 V.

4,8 V.

5,0 V.

Code: ACJL A triac is used to provide temperature control of an oven. The galley complain that the oven only reaches approximately 50 % of demanded temperature. Which of the following is a likely cause?

One of the main switching elements in the triac has failed.

The voltage supply to the oven controller is reduced by about 50 %.

Connection between the demand knob and the triac gate terminal has gone open circuit.

The triac has completely failed.

Which of the following measures is to be taken when working with batteries?

Recharge batteries immediately after discharge.

Install alkaline and lead-acid batteries in the same compartment.

Add new acid electrolyte to batteries that are in use.

Keep the batteries in discharged state.

Which of the following is an application of a piezoelectric sensor?

Accelerometer.

Tachometer.

Thermocouple.

I don’t know.

What is the minimum starting requirement of an emergency generator?

2 separate starting devices each with stored energy capable for at least 3 consecutive starts.

3 separate starting devices each with stored energy capable for at least 3 consecutive starts.

1 set of starting device with stored energy capable for at least 3 consecutive starts.

2 separate starting devices each with stored energy capable for at least 4 consecutive starts.

Code: RPHF 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.

The controller will is not respond to adjustment of set-point.

The controller will enter “sleep mode”.

It will take some time before the controller will react to a change.

Which of the following is the minimum acceptable value of insulation resistance for High Voltage equipment?

100 M Ohms.

1 G Ohms.

1 M Ohms.

100 k Ohms.

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 not continuously present, but will be present during normal operations.

Flammable mixture would not normally be present or it would be present for a short period only.

Flammable mixture is not present at all times.

Flammable mixture is continuously present or present for long periods.

Code: BOKI Which of the following methods may a diode be tested by?

Use a Digital Multi-Meter set to measure ohms in forward and reverse directions.

Use a Digital Multi-Meter set to check forward voltage and reverse current blocking.

Use an insulation resistance tester (Megger).

Connect to low ohms resistance tester.

Code: PDRS 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.

Temperature, pressure and dampness.

Humidity, pressure and surface contamination.

Flow irregularities in pipes are not caused by:

Straight pipe.

Throttling valve.

Elbow pipe.

Restrictive valve.

Which of the following is not a mode of a closed loop control?

Manual.

PID.

Modulation.

On-off.

A Multimeter is not suitable to measure:

Power.

Current.

Resistance.

Voltage.

Code: OKWA Continuity testing of a delta connected three phase induction motor yields the following results; U1-V1 = 4 ohms, V1-W1 = 4 ohms, W1-U1 = 4 ohms. What is the value of continuity resistance for each winding ie. U1-U2?

6 ohms.

2 ohms.

4 ohms.

12 ohms.

Code: KKHF Which of the following functions does the diode shown here perform?

Return inductive current to supply at switch off.

Allow Op Amp to top up +15 V rail.

Reference the transistor to +15 V.

Provide an overload route for transistor current.

Which of the following is an application of an capacitive sensor?

Barometer.

Tachometer.

Proximity sensor.

Piezoelectric sensor.

Code: FEYS Some ships generate electrical power at 440 Volts, but then step up this voltage to supply specific electrical equipment. One common example, may be to feed a large bow thruster. Why is this done?

A large bow thruster will draw very large currents at low voltage. Being typically remote from the generator, significant voltage drops would occur at low voltage.

The shipyard could not purchase High Voltage generating plant at the time of manufacture, so they used what was available at the time.

The overall ship’s electrical load does not justify High Voltage generating plant. This method allows more power to be delivered to the bow thruster at low running cost.

Manufacturers can supply High Voltage bow thrusters at less cost, and the power factor is improved.

Code: BFGX In an automatic temperature control system, operating with a PID controller which of the following settings or parameter adjustments may result in system oscillation?

Gain too high.

Gain too low.

Temperature change.

Too short D-time.

What are the main elements for Process Control?

Process, Sensor, Final control element and Controller.

Sensor, Modulation, Controller, Process.

Sensor, Controller, Noise, Final Control Element.

Resistor, Capacitor, Battery, Load.

Following shows circuitry of a peak detector. What is the output voltage curve, Vo if Vi is a sinusoidal input curve?

Vo will be the same sinusoidal curve but at a lesser amplitude.

Vo will peak when Vi is at the maximum, remain constant and fall to zero when Vi becomes negative.

Vo will spike when Vi is at the maximum/minimum point of the sinusoidal curve; zero everywhere else.

Vo will peak at a level less than Vi maximum voltage and remain constant throughout.

Code: THJL When selecting switchgear to work with High Voltage it is important to use an appropriate arc quenching medium. What is meant by arc quenching medium?

The gas, liquid or vapour which will minimise creation of an electric arc as contacts open.

Equipment which communicates information about the arcing.

The way in which the contacts separate as the switchgear operates.

A material which assists a welding process.

Code: PEBH A 250 V contactor has been fitted to a 220 V supply. Which of the following symptoms might be observed?

Contactor chattering (vibrating).

Contactor overheating.

Contactor wont operate.

Contactor constantly on.

Code: SRBP The circuit shows a transformer with two windings, N (1) = 2 000 and N (2) = 1 000 turns, on a common magnetic circuit. Assume that there are no energy losses in the transformer itself. Calculate the output voltage V (2) when the input voltage is V (1) = 100 Volt.

V (2) = 50 V.

V (2) = 400 V.

V (2) = 200 V.

V (2) = 10 V.

This circuit consists of a current source I, a change-over switch S, a resistor R and a capacitor C. The current/time figures 1 to 4 show possible changes in the current I when the switch S is suddenly shifted from position 1 to 2 at time t = 0. Which diagram is correct?

Figure A.

Figure B.

Figure C.

Figure D.

Code: AOML Which cell voltage is required to trickle charge a lead acid battery?

2,15 V.

1,2 V.

2,5 V.

2,0 V.

Code: VATG 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?

No.

Yes.

Depends on temperature to be measured.

Not applicable.

Code: TEOA High Voltage systems rely on the installed protective equipment being able to interrupt any fault in the system. Throughout the system, the fault level has been calculated, and under no circumstances must the system be modified to exceed this fault level. What is meant by fault level?

The amount of apparent power, that would be drawn from the generating plant, when a short circuit occurs at the bus bars.

The amount of apparent power that could flow into any fault at any.

The current level flowing into a symmetrical short circuit fault between all three phases.

The current level flowing into a dead short to earth at any point on the ship, directly from the High Voltage system.

Code: BGNJ The continuity resistance of a 100 m long × 25 sq. mm cable (rated at 100 A) is to be checked. Which of the following results would you anticipate?

Between 0,1 and 1,0 Ohm.

Between 0,1 Micro Ohm and 1,0 Micro Ohm.

Between 0,1 and 1,0 M Ohm.

Greater than 1 M Ohms.

Code: XQSO When starting three phase induction motors which of the following starting methods will immediately apply rated voltage to the machine?

Direct on Line.

Star Delta.

Auto – transformer.

Soft starter.

Code: HQPE 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.

Short circuit winding between W and U.

Partial fault between W and U.

Short circuit between V and Earth.

Code: RGBR What is the advantage of a transmitter with a narrow measurement range?

Better linearity and increased accuracy.

Easy installation.

Do not need any calibration.

Lower purchase cost.

Code: UGPX 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 level of the electrolyte.

Measure the battery voltage.

Measure the temperature of the electrolyte.

When polarity of the incoming power line is reversed, what happens to the DC motor?

Motor rotates in the reverse direction.

Motor explodes.

Motor still rotates in the same direction.

Motor stalls.

Code: BXUA This circuit consists of a voltage source V, a change-over switch S, a resistor R and a capacitor C. The voltage/time figures 1 to 4 show changes in the voltage V(C) when the switch S is suddenly shifted from position 1 to 2 at time t = 0. Only one of the diagrams is correct. Which?

Figure 1.

Figure 2.

Figure 3.

Figure 4.

Code: NCNE 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 l(2) when the current l(1) = 2 A.

l(2) = 4 A.

l(2) = 2 A.

l(2) = 1 A.

l(2) = 8 A.

Code: EKVD 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?

22 Ohms.

10 Ohms.

0,1 Ohms.

220 Ohms.

Code: UDFB Which electronic component or system is this graphical symbol illustrating?

Bandpass filter.

Transformer with ferromagnetic core.

Electric heater.

3-phase sine-wave generator.

Code: GNXL Can a ZENER BARRIER be installed in a hazardous area?

No, as only the output from the barrier is intrinsically safe this is not allowed.

Yes, that’s what the zener barrier is made for.

Only if properly marked for such installation.

Only in equipment operating on very low voltage.

Code: DBRX When there is a need to interrupt current flow in a high voltage system it may be very difficult to quench the electrical arc which is generated at the circuit breaker contacts. Which of the following arcing media is commonly found in high voltage marine switchgear?

Vacuum.

Water.

Air.

Oil.

Code: XIWJ The circuit shows a full-wave bridge rectifier. Which electronic component should be connected between “a” and “b” in order to obtain reduced ripple voltage to the load RL.

Capacitor.

Inductive reactor.

Resistance.

Zener diode.