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 can be accommodated in a separate contactor deckhouse instead of in the winch assembly. This increases the amount of cabling but on the other hand it economises deck space in the vicinity of the winch, making for cleaner lines and unobstructed viewing by the operator. It also facilitates maintenance work which in any case is not always opportune to carry out when the ship is in port and when the winches are in use. While at sea maintenance can be carried out under protection from the elements. In every winch, etc., in which the load is lowered while the motor is mechanically coupled such as in systems employing power lowering it is essential to prevent the load taking charge and lowering at a speed which will damage the motor armature. To safeguard against this contingency centrifugal brakes are provided in some cases and they are so set as to enable heavy loads to be lowered with an
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.
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