P&D revison Flashcards
How many diesel generators on a ship?
4
What does EDC stand for
Electrical Distribution Centre
How many EDC’s are fitted to a generic distribution system
There are 4 EDC’s
What does MCCB stand for
Moulded Case Circuit Breaker
List the 5 main breakers on a generics distribution system
Supply breaker, shore supply/ship alongside breaker, Bus bar linking breaker, Interconnector breaker, Feeder breaker
What is the power book and when is it used
Shows distribution of 440V, used when tracing which services are fed from the fuse panel, transformer, MCCB and EDC.
What is the lighting book and when is it used
Shows 115v/230v and is used in the same way as the power book
What is the reference book and when is it used
The reference book is used in conjunction with the power book and lists all fittings, number fitted, component symbols and pattern numbers.
What is the ratio for 440v fuses regarding fuse discrimination
3:1
What is the ratio for 115v fuses regarding fuse discrimination
2:1
Explain breaker discrimination
Breaker and fuse discrimination it would be impossible for a fault on a mess deck kettle to trip a main generator.
What does MCR stand for
Machinery control room
What does PCC and SCP stand for
Primary control centre and Secondary control position
List the meters fitted to a switchboard generator section
Voltmeter, ammeter, KW meter, frequency meter, syncroscope, earth fault indicator
Where are the breaker operating switches found and what are they called
Start/stop, selector, control and discrepancy switch located in PCP
What are the rules regarding to earthing the ship when connecting shore supply
The shop must always be earthed to either jetty or ship alongside by at least 2 points, not less than half the ships length
What is used to confirm correct phase rotation with respect to shore supply
The phase sequence indicator (2 lamps) the right one should be brighter
What would happen to a motor if a phase rotation is wrong
Motors would run backwards
List 3 types of hand changeover switches
Normal/alternative, normal/emergency, normal/alternative/emergency
List 3 kinds of changeover switches
Hand changeover, automatic changeover, remote operated changeover
What are where are 440v earth testing facilities found
Earth indicator light located on the switchboard so have audible alarms
Why are there separate 115v testing facilities
115v is transformed supply and the secondary windings (output side) is not physically connected to the primary winding
