Category: EK ELECTRICS

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Describe how the starting torque of electric induction motors may be improved by using EACH of the following (a) Wound rotor (5) (b) Double cage (5) Electric motors Mar 2019 (Q10)

EK Electrical Mar 2019 (Q9)

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(a) Describe, with the aid of a sketch, a static excitation system for a generator (8) (b) Explain TWO advantages of static excitation system (2) AC Generator Mar 2019 (Q9)

EK Electrical Dec 2018 (Q11)

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(a)With reference to alkaline battery cell (i) Describe a typical cell, stating the materials used (4) (ii) Describe the process that takes place during discharge and charge (2) (iii) State the effects of overcharge (2) (b) State the advantages of an alkaline cell compared with a lead acid cell. (2) Batteries & Emco power supplies…

EK Electrical Dec 2018 (Q10)

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During a complete loss of electrical power, essential vital services can be maintained by means of an Uninterrupted power supply (UPS) (a) Describe, with the aid of a block diagram, the operation of an AC input UPS arrangement (7) (b) List SIX essential services that UPS may support. (3) Batteries & Emco power supplies Dec…

EK Electrical Dec 2018 (Q9)

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With reference to paralleling AC generators (a) Outline the requirement for synchronization (2) (b) Explain how KW power is shared (1) (c) Explain how KVar power is shared (1) (d) State SIX types of damage that may be caused when machines are incorrectly synchronised. (6) Generator & circuit protection Dec 2018 (Q9)

EK Electrical Oct 2018 (Q11)

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With reference to lithium-ion batteries: (a) Explain why this type of batteries has been adapted for shipboard use (4) (b) State ONE advantage and ONE disadvantage of lithium-ion batteries (2) (c) Define EACH of the following terms (i) Cell drift (2) (ii) Thermal runaway (2) Batteries & Emco power supplies Oct 2018 (Q11)

EK Electrical Oct 2018 (Q10)

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(a) Sketch a circuit diagram of an emergency generator power supply and distribution system, indicating the essential services provided. (6) (b) state the emergency generator regulations. (4) Batteries & Emco power supplies Oct 2018 (Q10)

EK Electrical Oct 2018 (Q9)

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Describe, with the aid of a circuit diagram, the operation of a shaft generator that uses a frequency converter (10) AC Generator Oct 2018 (Q9)

EK Electrical Jul 2018 (Q11)

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(a) Explain the principle of operation of an insulation resistance test, stating why the test is carried out on a regular basis (6) (b) Describe how EACH of the following electrical tests is carried out (i) Resistance (2) (ii) Continuity. (2) Electric motors Jul 2018 (Q11)

EK Electrical Jul 2018 (Q10)

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