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THIED POST

    The electronic and   alarm measuring systems   are designed for centralized supervision of processes on board ships. 2. Such systems are designed to meet the special requirements in marine applications. 3. The design of the alarm systems comprises a limited number of  standard modules , and offers an economical and flexible solution for all system sizes — from small alarm systems with a few channels, to complex systems with data logging and alarm print-out functions. 4. The signals from analog and digital transducers are processed in the system and allow for simple and clear monitoring of process activities. The occurrance of abnormal conditions initiates audible and visual alarm signals.

SECOND POST

  hese auxiliaries, in the main, comprise cargo winches (which may include warping as a subsidiary duty), cranes, capstans, warping winches, windlasses and   hatch-cover winches . Except for cranes, each of these may sometimes be used for duties other than those for which they are primarily intended. The systems of control as between these various applications bear a similarity but with variations to suit the operating conditions. It will be convenient to deal with them under their different headings, but there are divergencies between the methods favoured by different makers and descriptions will therefore be confined to representative schemes. Electro-hydraulic winches  do not call for special mention as they use a continuous running motor, which can be either a.c. or d.c. They can be operated either singly or in groups from one pump. Many electrical deck auxiliary schemes make use of contactors for control purposes and where these are of such size and numbers as to warrant it they c

NEW

 ETO ORAL QUESTIONS A part from the fact that good insulation resistance is an essential condition for maintaining service, the regular recording of insulation resistance values is undoubtedly the best method of detecting deterioration and of indicating when remedial action is desirable, or perhaps essential, in order to prevent complete failure. Insulation resistance (IR)  should accordingly be measured and recorded at regular intervals, the recording being preferably on a separate log-sheet for each important machine or circuit, so that each fresh reading can be compared with previous values and any downward trend immediately observed. It cannot be too strongly emphasised that, subject of course to reasonable minimum values being maintained, trends are more important than actual values; a single value is of comparatively little significance. The intelligent interpretation of results is therefore of great importance and a general appreciation of the factors involved is essential.