Read and translate the text.

  1. Additional text.
  2. B) Answer the questions on the text.
  3. B) Answer the questions on the text.
  4. B) Answer the questions on the text.
  5. B) Explain what are hedging techniques mentioned in the text.
  6. B) Write down 3-5 questions about the text.
  7. B) Write down 3-5 questions about the text.

It is often convenient to group motor driven auxiliaries according to their function, e.g. fuel and lubrication oil services, accommodation ventilation systems, machinery ventilation systems, and domestic service systems. The auxiliary motors would be supplied from grouped motor controllers located either in the engine room, in a machinery control room or in a convenient location close to the auxiliary motors. This can often simplify the machinery control functions and required protection systems.

On small ships, e.g. tugs, etc., such grouping is not economical and the major ship's auxiliaries are normally supplied directly from the main switchboard. In this case the motors would be provided with individual starters located adjacent to the motor. For high speed vessels where weight is important, minimum cable weight may be achieved using a "non-distributed" distribution scheme.

Auxiliary motor controls should be arranged in consideration of the general control philosophy applied to the machinery control systems. For ships that do not have automated machinery operation, the most economic method of control is to provide local starters for each auxiliary motor supplied from power panels located in the same or adjacent spaces. These motors would be manually controlled (start and stopped), locally at the motor's controller (starter). This arrangement minimizes cable costs.

When a centralized machinery control system is required, cables for the motor control functions can be installed back to the machinery control room and the starter push buttons located on a centralized machinery control console. Alternatively, the motors may be grouped together on motor control centers located inside the control room. The motor control functions can then be left on the motor's starter at the MCC or again wired back to a central control desk.

When fully automatic machinery control is required, these techniques are now in common use and micro-processor devices control the ship's machinery through video display units located in the machinery control room or on the bridge. The ship's auxiliaries are generally controlled with programmable logic controllers (plc's) installed inside the motor control centers and linked through a data bus to the machinery control location. When this type of system is used, the motor control centers can be located either together in the machinery control room or alternatively, distributed throughout the ship close to the motors being controlled.




Give adequate Russian equivalents of the italicized words. | Read and translate the text. | . | , . | Lesson 5. | Find the international words in text. | Read and translate the text. | Make up the sentences. | 䳺 . | , , . |

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