PRINCIPLES OF NAVAL ENGINEERING 



HAINTENANCC INDEX PACE 

 0PHAV FORH 4700-} I4.M) 



SUKEAU MCE CONTROL NUHeE* E-13/62-65 



Figure 16- 15- . — Maintenance Index Page. 



98.171 



either the turbine or the generator. A hand trip 

 may be seen in the illustration of an overspeed 

 trip (fig. 16-13). 



Some auxiliary turbines (generator turbines, 

 in particular) are fitted with low oil pressure 

 alarms to warn operating personnel when the lu- 

 bricating oil pressure becomes dangerously low. 

 When the oil pressure drops below normal, a 

 pressure-actuated switch completes an electri- 

 cal circuit to sound an audible alarm. Control 

 systems may also be arranged to trip the tur- 

 bine if lubricating oil pressure drops too low. 



TESTING SAFETY DEVICES 



Speed limiting governers and safety trips 

 must be tested and maintained in accordance with 

 the requirements set forth by the Naval Ship Sys- 

 tems Command and at the intervals specified by 

 the Planned Maintenance Subsystem of the 3-M 

 System. Testing must be done under the super- 

 vision of the engineer officer and the results of 

 the tests must be entered in the engineering log. 

 Figure 16-15 shows some of the required tests 

 and maintenance requirements (Maintenance 

 Index page) for a turbogenerator. 



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