Tag: #ukmmarineengineering

—

by

(a) Explain the principle of operation of an insulation resistance test, starting why the test is carried out on regular basis (6) (b) Describe how EACH of the following electrical tests is carried out (2) (i) Resistance (2) (ii) Continuity (2) Mar 2021 (Q11)

EK Electrical Mar 2021 (Q10)

—

by

With reference to large electrical transformers on board ships (a) State where these transformers may be used (1) (b) State a typical efficiency range for a transformer (1) (c) State the regulations pertaining to transformers (3) (d) State the protective devices that are fitted (2) (e) Describe the maintenance requirements (3) Mar 2021 (Q10)

EK Electrical Mar 2021 (Q9)

—

by

(a) Describe, with the aid of a sketch, the constructional details of a squirrel cage rotor as fitted in an induction motor (7) (b) Explain why some rotors have a double cage (3) Mar 2021 (Q9)

EK Electrical Dec 2020 (Q11)

—

by

With reference to electrical system protective devices, explain the purpose of EACH of the following: (a) Overcurrent protection; (2) (b) Short circuit protection; (2) (c) No-volt protection; (2) (d) Reverse power protection; (2) (e) Preferential tripping. (2) Dec 2020 (Q11)

EK Electrical Dec 2020 (Q10)

—

by

With reference to braking of a.c. induction motors: (a) Explain why braking may be required; (2) (b) Explain why electrical braking is preferable to mechanical braking; (2) (c) Explain the term plugging; (2) (d) Describe how dynamic braking is achieved. (4) Dec 2020 (Q10)

EK Electrical Dec 2020 (Q9)

—

by

Describe, with the aid of a block diagram, the operation of a load sensing electronic governor controller for an AC generator. (10) Dec 2020 (Q9)

EK Electrical Oct 2020 (Q11)

—

by

(a) Explain, with the aid of a sketch, the principle of operation of an earth leakage detection system of the instrument type. (6) (b) Explain why an insulated neutral system is used extensively on board ships. (2) (c) State, with reasons, why a single earth fault on an insulated neutral system should always be cleared…

EK Electrical Oct 2020 (Q10)

—

by

With reference to star delta starters used for three phase induction motors: (a) Explain in detail why this type of starter is employed; (4) (b) Explain, with the aid of a circuit diagram, the sequence of operation of a star delta starter. (6) Oct 2020 (Q10)

EK Electrical Oct 2020 (Q9)

—

by

With reference to the protective devices fitted to a main alternating current generator, explain EACH of the following (a) Overcurrent and short circuit protection (2) (b) Generator negative phases sequence (2) (c) Loss of field (Excitation) (2) (d) Under voltage (2) (e) Reverse power (2) Oct 2020 (Q9)

EK Electrical Aug 2020 (Q11)

—

by