Yacht-engineering is a job that requires a lot of skills. And one of the major tasks yacht marine engineers have to do on board is to deal with the yachts electrical system and electronic systems. This includes designing and fabricating this electrical system, documenting, testing and troubleshooting this system before installing it, observing changes in the production process and providing input on how to change the electrical system accordingly.
The ability to do all this is key in order to provide a safe yacht with no fire hazards or electric shocks for the people on board. In addition, these different levels of expertise will help yacht marine engineers not only avoid mistakes and problems onboard but also come up with innovative ideas that may be implemented in the production process of yachts, making them more safe and efficient.
Most marine engineers around the world have at least a basic knowledge in yacht-engineering. However, there are also some specific techniques that may be required only for certain jobs or areas of expertise. For example, on board construction relies heavily on 3D modeling software such as Catia and Solidworks in order to help the engineers build a wireframe of the yacht’s electrical system. This can either be done from scratch or as a modification of an existing model in order to match some new specifications. In addition, marine engineers must have good working knowledge on basic electronics since they will make connections between sensors, computers and actuators.
Some of the top yacht-engineering techniques every marine engineer should master include:
– Designing and fabricating the yachts electrical system. This includes choosing between different wire types (such as copper, aluminum or fiberglass), cable types (e.g. twisted pair) and insulation materials (e.g. polyethylene). It also includes choosing the right circuit breakers, wires and fuses.
Small boats usually have a simple electrical system with only one DC wiring. This type of electric power supply uses one positive wire (called “Hot”) and one negative wire (called “GND”). The Hot wire is connected to all the devices in order to provide them with electricity. The GND wire is connected to the ground and to every device that has metal parts in order to prevent electric shocks. In addition, marine engineers must be careful when using DC circuit breakers since DC current flowing through fuses will heat up the wires until they burn down or melt.
Upgrading from a simple single-wire system may be a good idea in order to provide more power and to also be able to monitor some devices (such as the wiring and other sensors). Using multiple wires enables the use of AC current, which is more efficient than DC current. This means that most electronic components don’t have any problem functioning with 50 or 60Hz.
Traditional AC systems use three wires: a positive one (Hot) and two negative ones (GND). This type of electrical system is called “Three phase”. It can be used to provide more power for devices, such as the engines or air-conditioning units. Another benefit of a Three phase system is that it allows monitoring and managing each wire separately, which is not possible with a single-wire system.
This is what the layout of a three-phase AC current looks like:
The use of this type of wiring enables monitoring not only by voltage but also by amperage, which helps detect electrical problems and understand how much power each device draw from the power supply (which is important for smaller yachts).
But what happens if a wire fails or there is an overload? It would be impossible to use breakers with this type of system, since the problem can show up only at certain times (e.g. some phases may stop working but not others). This is why instead of using them, marine engineers must choose circuit breaker panels that disable individual wires. This is not as efficient for the power supply, but it will save your boat from fire just in case one of the panels malfunctions.
Using large boats as an example, a good combination of wire types and insulation material may mean more safety and less maintenance over time:
– Documenting, testing and troubleshooting the electrical system before, during and after installation for adherence to safety standards. This includes:
– Verifying the compliance of an electrical system with a yacht’s class rules by comparing it with the corresponding certificate of compliance (CoC). – Measuring each wire and cable as well as each circuit breaker (in order to make sure they are not overloaded) – Verifying that DC system fuses or breakers are in accordance with the standards. – Checking that bus bars and all wiring installations are insulated by observing insulation continuity (e.g. resistance must be within limits)
– Measuring the impedance of each wire and cable using an electric tester, which will help determine if there is water penetration through cable sheaths. – Testing and troubleshooting each circuit breaker panel by measuring its impedance in order to verify that it is not defective or overloaded.
– Monitoring the power distribution system over time using a digital voltmeter, which will help detect spots with low voltage (caused by resistance) or high voltage (caused by electrical faults).
– Sizing the electrical system in order to estimate how much power the yacht requires, which will help determine if all breakers are of adequate size. This means that you must know:
– The total energy and power consumption of each device (which can be found on its technical sheets or by multiplying volts times amperages) – How long each device is used during a day and how many days a year (this is needed to estimate the total power consumption of each device)
– Calculating if the electrical system has enough capacity by dividing the power required by the number of hours it will be used
– Checking if there are any gaps in devices wiring which could cause an overheated wire or open switch.
– Checking if the wires and cables are properly installed (e.g. verifying that a wire is soldered correctly, at the correct place and orientation)
They use even more ways to monitor systems on large yachts nowadays, but then again you can always hire an engineer to check your boat or maybe read some books about yacht electrical engineering.
All of these techniques and procedures are vital for your yacht’s health, not only because they ensure safety and compliance with standards, but also because they help you save money by preventing future damage to your boat (since repairs will be less expensive if an electrical system is well documented).
Although the first two techniques mentioned above can be learned in a few days, it may take years to master them. One of the most important skills in yacht engineering is the ability to troubleshoot electrical problems (e.g. when the lights don’t work or a breaker suddenly trips). In order to do so, you must be prepared:
– Make sure that there are no signs of water penetration (e.g. condensation signs, rust on the fixtures). – Make sure that all connectors are tight and in place. – Make sure that there is no loose wiring or damaged parts (e.g. burnt wires, broken cabinets)
– Test each circuit breaker by turning them on one by one to see if they trip properly or if any lights dim. To troubleshoot an electrical problem you must be able to:
– Locate the faulty part (e.g. burnt wire, broken cabinet) – Understand how a circuit breaker works in order to know which part of it is faulty – Understand which devices use what circuits by noting their location and using common sense – Know how to test the circuit breaker and which part of it is faulty without having to look at its inner working (e.g. test all the switches, make sure that they are in place, etc.)
– Know how to repair or replace a broken wire or component – Understand what each device does (e.g. what a light switch does in the restroom, where this switch is located, how to turn it on and off) – Check the wiring diagram of each device in order to understand what components are used for (e.g. read a light switch’s schematic drawing)
– Know that a circuit that has power going into “A” and out of “B” will always have power in “B” even if you open “A”, since the wiring is double-insulated – Make sure that all wires and cables are properly insulated (e.g. make sure that there are no bare wires which could be tripped on) – Replace broken components with the same type of component (e.g. replace a light switch with a new light switch)
Since you’re a yacht engineer, you’ll likely need to replace electrical and electronic parts.