MOTOR STARTING METHOD
Star Delta Starter
This
is means of reducing
starting current of induction motor by initially connecting to the stator winding to ‘STAR’.
Once
the motor comes up to
speed (68%) to be connected
in DELTA.
When
motor start in ‘STAR’
it has the effect
of:
Reducing...
LATEST ELECTRICAL TECHNOLOGY MMD ORAL Q & A PART-6
(a) Explain about BJT (Bipolar Junction Transistor),Uni-junction transistor.
(b) Describe about NPN and PNP transistor with sketch.
(c) Describe about Thyristor,GTO(gate turn off thyristor)
(d) Describe about MOSFET operation, Snubber circuit.
(a) BJT (Bipolar Junction Transistor)
Three terminal device,...
ALTERNATOR SYNCHRONIZATION
SYNCHRONIZING AND
PARALLELING OPERATION OF ALTERNATORS
Main
generator units(steam turbine, diesel driven & shaft driven) have to be run
in parallel to share a total load that surpass the capacity of a single machine
specially when discharging cargo, loading...
LATEST SOLAS & MARPOL AMENDMENTS
MARPOL
1) 1st March 2018 – Data collection system for fuel oil consumption on ships.
IMO documents : MARPOL Annnex 6, regulation 22, 5000GT & above.
Entry in to force(EIF) under tacit acceptance procedure : 1st March...
CIRCUIT BREAKER
A circuit breaker is an automatic device which is designed to stop the flow of current in an electrical circuit and save the electrical circuit from damage caused by overload or short circuit.
Its main...
SEMICONDUCTOR
A semiconductor is a type of material posses electrical conductivity between conductor and an insulator.They are neither good conductor nor good insulators. The electrical resistivity of semiconductor generally decreases strongly with increasing temperature.Semiconductor atoms...
MAIN SWITCH BOARD
Survey of MSB
Proper cleaning to be
carried internally as well as externally normally carried out when board is
completely dead (all generator stopped and prime mover locked off). Inspect for
dirt and dust (electro clean and vacuum...
RUDDER ANGLE INDICATOR
It is a device which is used to indicate the current position of the rudder blade, normally fitted in the wheelhouse, bridge wings and engine control room.
A rudder angle indicator consists of a feedback...