If one phase is short-circuited to ground, there will flow a ground fault current. Its magnitude depends heavily onthe method of system grounding, which are: UngroundedGround fault currents will still flow due to capacitive coupling between healthy phases and ground, typically in the order of a few amps in a ship installation. Low resistance groundingGround […] Read more
Any ship electrical drawing representing an ship electrical installation or ship circuit uses specific symbols to represent the various ship electrical devices in shorthand. This provides the electrical engineer with an overview of the circuit or installation and is particularly useful for troubleshooting onboard. It is important to be familiar with the various ship electrical […] Read more
Despite the great interest in the application of electric propulsion to warships, there are quite few conventional surface warships with pure electric propulsion, but more are being projected. For sub-marines, electric propulsion with diesel engine generation and battery storage, fuel cell or nuclear power plant is applied. Electric propulsion for war ships does not conceptually […] Read more
Ever since AC generation and distribution has been introduced on a large scale on ships around 1950, there has been debate about the type of distribution system. The main focus with the type of distribution system is the treatment of the systems neutral with respect to grounding. When selecting the grounding method on ship the […] Read more
Sometimes a few turns in the secondary winding of a transformer experience a partial short, which in turn causes a voltage drop across the secondary.... Read more
To successfully carry out the various test procedures suggested in this manual, certain test instruments are essential. The following lists detail the... Read more
The maintenance requirements for cage-rotor induction motors are very simple: contact resistance low Keep insulation resistance high and Lubricate cor... Read more
A vessel has an extensive electrical system designed to carry out more functions than can be found in a small community. Lighting, instrument panels,... Read more
OILER-ELECTRICIAN TO KEEP WATCH AS AN OLR + DUTIES OF ELECTRICIAN. 1-ST CL.MOTORMAN CERT IS A MUST !... Read more
The Assistant Electro Technical is responsible for the maintenance and repair of the electrical plant and associated electrical systems as designated by the Chief Electro Technical Officer and Chief Engineer. Specific Areas of Responsibility include but are not limited to the following: o Onboard Lighting Maintenance. o Onboard Passenger and Crew Cabin Electrical Systems. […] Read more
The Assistant Electrician is responsible for supporting the maintenance of all electrical equipment and systems as directed by the Chief Electrical Engineer to ensure safety operation, environmental protection and passenger comfort. Responsible for the maintenance and repair of any electrical systems onboard as directed by the Chief Electrical Engineer. Must have good knowledge of the […] Read more
Ship’s large power equipment and processes utilise high forces. Electrical, mechanical, thermal and chemical changes produce the desired operation. Very high values of ship voltage, current, power, temperature, force, pressure etc. create the possibility of danger in an ship engineering system. To minimise the safety risk to personnel and equipment a system must be designed […] Read more
The direct on line ship motor will rotate with a speed directly determined by the ship network frequency. For propulsion, thrusters, pumps, winches, etc., there might be significant savings in ship power or fuel consumption of ship generators by reducing the no-load dependent losses in operations. Also, controllability of the driven load will be greatly […] Read more
The control circuit is derived directly from the ship power circuit. The control circuit provides power to the timers, relays, switches and other components: necessary to control the operating contacts of the main component in the power circuit. The ‘control circuit’ controls the normally open contacts (and in some cases normally closed contacts too) in die […] Read more
What does an electro technical officer do? An electro technical officer handles several responsibilities on vessel mainly related to electrical systems. Like most jobs at sea, as a ship officer handling electronics on a vessel, you are most likely to work under a chief engineer who supervises everything on a ship. And while under a […] Read more
The cooling system runs on the following standard layout: The central freshwater cooling system with single-stage scavenges aircooler and a separate HT circuit. As freshwater is the standard cooling medium of the scavenge air cooler(s), this involves using a central freshwater cooling system. The central freshwater cooling system comprises “low-temperature” (LT) and “high-temperature” (HT) circuits. […] Read more
Most multimeters can only measure current up to 10 A maximum. The current measuring facility is intended only for small current components and, in particular, for electronic circuits. The instrument will almost certainly be damaged if it is used to measure the current to motors and other power circuits. The basic current range can be […] Read more
Power currents (a. c.) can be measured simply by means of a clamp meter which acts as a current transformer. The instrument tongs are clipped round a single insulated conductor – the circuit is not interrupted. The value of current is obtained from the magnetic flux strength around the conductor and is usually displayed on […] Read more
Embossed metal tags are used to identify cables throughout the vessel. The tags are located at the distribution panel and the component. Tags are also attached to the cables where penetration of the bulkhead is necessary. The tag code will start with the type of circuit it is. Vessels use P to indicate power distribution panel […] Read more
Electronic equipment such as programmable logic controllers (PLCs), timing relays and coupling modules that can be affected by other components on ship electric network, are commonly used with conventional switching equipment on ship electrical system. For example, disturbances can be created by inductive loads when relays’coils are switched on or off. To reduce the disturbance […] Read more
