Difference between governors fitted on main propulsion engine and Generator.

-
All marine vessels need some sort of speed control system to control and govern the speed of marine diesel engine used for propulsion. It would be really impractical and dangerous to have a ship without speed control mechanism fitted on it, and can lead to accidents such as collision or grounding.
       The speed control mentioned above is achieved with the help of a governor. Main role of a governor is not to increase or decrease the speed which can be done via fuel control system ( similar to an accelerator on your car) but once the speed of the engine has been set, the job of the governor is to maintain that despite the variations in load. In other words the governor controls the speed variation and keeps the speed within restrained limits despite these variations.
      As per IACS each main engine is to be fitted with a speed governor so adjusted that the engine speed can not exceed the rated speed by more than 15%.

Generator on board a ship needs to maintain constant frequency. To maintain constant frequency the prime mover  should run at constant speed. So the governor fitted on this type of prime mover should be able to maintain constant speed to maintain constant frequency. As per IACS each generator should be fitted with speed governor which will prevent transient frequency variation in the electrical network in excess of + or - 10% of the rated frequency.

so it can be concluded that governor fitted on main engine is a constant load governor. It maintains constant load at different speed setting set by the fuel lever. Where as a governor fitted on a generator is a constant speed governor. It maintains the engine rated speed despite of load variations.
                                                                                                                                                      

Comments

Post a Comment

Popular posts from this blog

CRITICAL EQUIPMENT AND OPERATION UNDER ISM CODE.

-
Critical equipments are equipments whose failure will lead to a potential hazardous situation or an accident, thereby causing injury to personnel or loss of life or damage to marine environment or property. This causes deviation or failure of the ISM objective 1.2.2 of ISM code. PROVISION IN ISM :- Element 10.3 of ISM code states----      The company should establish procedures in its safety management system to identify equipment and technical system, the sudden operational failure of which may result in hazardous situation. The SMS should provide for specific measures aimed at promoting the reliability of such equipment or systems. These measures should include the regular testing of standby arrangement or equipment or technical systems that are not in continuous use.      Hence SMS must have with respect to the critical equipment have procedures:- 1) To identify them 2) To ensure their test and functional reliability 3) To establish and use the alternative arrangements on
Read more

Various codes of PSC inspection and how to present to PSCO in case IOPP equipment is not working

-
Following are the various codes which are used to represent Action to be taken by vessel against the deficiency reported:- Deficiency Action Codes 10 deficiency rectified 15 rectify deficiency at next port 16 rectify deficiency within 14 days 17 rectify deficiency before departure 18 rectify deficiency within 3 months  30 detainable deficiency 99 other (specify) Note: For ISM deficiencies, only code 10, 18 and 30 can be used. Restrictions on Updating Codes Both codes 15 and 16 can only be updated to code 10. Code 17 can only be updated to code 10, 15, 16 and 99. Code 18 can only be updated to code 10. Code 30 can only be updated to: - code 10 or 18 (ISM def.) - code 10 or 99 (non - ISM def.) Code 18 can only be updated to code 10. We will discuss one case where 15 ppm equipment has started malfunctioning just before the arrival of the port. After investigating it was found that the  coalescer filter has become very dirty and because of this th
Read more

CLEAR GROUND FOR DETAILED INSPECTION DURING PSC INSPECTION

-
CLEAR GROUNDS:- Evidence that the ship, its equipment or its crew does not correspond substantially with requirement of relevant convention or that the master or crew members are not familiar with essential shipboard procedures relating to the safety of ship or prevention of pollution.     Clear grounds to conduct a more detailed inspection include:- 1) The absence of principal equipment or arrangements required by convention :- e.g. MARPOL annex 1 requires that ship above 400 GRT and above must have an OWS with automatically stopping device, if effluent exceeds 15 ppm. Absence of this principal equipment will lead to detention. 2) Evidence from a review of the ship's certificate that it is clearly invalid: - e.g. Safety equipment certificate found invalid since no renewal survey was carried out. 3) Evidence that the ship's logs, manuals or other required documentation are not on board, are not maintained or falsely maintained:- e.g. ORB part 1 not present on board or in
Read more