Boating electronics fundamentals for beginners

Figure 2 - Middle Powered Network -

Our Solutions Engineer, Josh Keets, was recently interviewed by Powerboat & RIB Magazine to share his thoughts on the key concepts for any boater to understand when it comes down to having a comprehensive grasp of boating electronics. There are, specifically, a couple of basic, fundamental ideas which must be understood before delving deeper. These are power, and protocols (data formats).

In boating electronics, there’s a few different protocols that the on-board electronics may use, and it’s important to understand how these devices are connected, depending on whether they share the same protocol. The main three data protocols you will come across are NMEA 0183, NMEA 2000 and SeaTalk 1.

It’s not possible for me to explain them all here in detail, but I have written pieces on NMEA 0183 and NMEA 2000, plus a separate article on understanding these data protocols which can be found via the Actisense Website. To try and explain it as simply as possible, SeaTalk 1 is a Raymarine proprietary messaging format which utilises it’s own unique wiring, communicating via serial. NMEA 0183 is an NMEA standardized format, which operates on both RS-232 and RS-422 serial comms, depending on which variant of NMEA 0183 the device uses. This is a 1 to 1 connection method unless you use multiplexers and buffers.

Intelligent Type Approved NMEA 0183 Buffer - PRO-BUF-2
Intelligent Type Approved NMEA 0183 Buffer – PRO-BUF-2

NMEA 2000 is very different as it uses a CAN BUS system, allowing all of your on-board NMEA 2000 electronics to communicate in a seamless way, all connected to one network. NMEA 2000 cannot be connected directly to NMEA 0183 devices, and a converter is needed. The same goes for SeaTalk 1 and NMEA 2000, and SeaTalk 1 with NMEA 0183.

Every device must have power, whether it come directly from a battery terminal, a power bank, an NMEA network. The method in which devices are powered is largely influenced by the type of device they are, and the amount of power they require. NMEA 0183 devices are all powered independently, whilst NMEA 2000 devices are powered by the network supply or independently, depending on the power consumption of the device.

NGW 1 Wiring Connections2
NGW 1 – NMEA 2000 Gateway

Of course, when we talk about connecting devices with Power, we also need a Common or Ground. All your electronics should be grounded, and there should be one common grounding point on the vessel. Having multiple grounds can create ground loops, which I won’t go into now, but to put it simply; they’re not good for your electronics!

Advice for a new boater or a beginner in boat-DIY

Always do your research… it is important to understand if the electronic equipment you are choosing is fit for purpose, but also that it isn’t overkill. MFDs are a perfect example of this;

Acting as the ‘brain’ or control centre of your NMEA 2000 network means that it must be capable of performing all tasks you need it to do. This could vary from just acting as a simple chart overlay, through to radar and sonar imaging connectivity for commercial fishing. With the wide range of products available on the market, it can be a little overwhelming, Personally, my best advice would be to speak to the manufacturer directly, to ensure that their equipment is capable of doing everything you need. On the flip side of this, you don’t need a $2000 MFD when a $400 display would do everything you needed.

Once you have done your research and are happy with the equipment being installed, the next piece of advice is to plan. Draw a layout of your install, including networks, cabling and device install location. This will make it much easier when it comes to doing the physical install.

When the schematic is being created, be sure to visually inspect the area you are planning on running cables or installing devices. Whilst in theory the plan will work, there is always the chance of it not working in practice. For example, you may plan to run cables through the vessel, but in reality this is a solid material with no space for a cable. Save yourself the headache by double checking before you install. If you have any doubts, or simply feel like you aren’t qualified for the task, always reach out to a certified ABYC / NMEA technician and have them come out for the job. Sometimes it’s better to pay a professional than do it yourself, especially when installing power systems or safety critical devices.

Finally, ensure that you test your electronics after install, and no, by that I don’t just mean turn it on and off to check that it powers up. Some electronic devices will require calibration and information entered into them, they won’t just work out of the box. This is essential to any equipment install, no matter how simple the device is. A certified installer will always perform calibration and tests after installation is completed, they don’t want to make the trip twice after finding out that their install isn’t working properly!

Picture this scenario; you’ve just installed a brand new AIS and VHF, two safety critical devices on board. You’ve turned them on and off whilst docked and you think they work. Little do you know that there’s actually a power issue with your wiring and the device is going to lose power 20 minutes into your journey. An hour later you have a mayday situation out at sea, with no cell coverage available. Now you’re stuck with no radio, no way of identifying your vessel, and limited methods of contact. Performing an extensive test run with your new equipment around a local marina would have highlighted this issue and saved you from this situation. Testing equipment is more important than installing it.

I do appreciate that equipment can fail at any time for a number of reasons. At the end of the day it is an electronic device with hundreds of components inside which can go wrong. However, the aim is to minimize risks and ensure safe travel. I can’t guarantee 100% operation for the next 10 years, but a new boater is at a higher risk than a seasoned one when out on the water! Minimise your risk, maximise your confidence in the boat and equipment on-board.


For those new to this, where can they go to get information and advice?

There is a vast amount of information out there, but sadly not all of it is accurate or true. The best place to go for answers about specific equipment will always be the manufacturer, failing that then reach out to a certified NMEA Installer.

For those who want to learn the basics themselves, or further expand their knowledge then we have a wide range of info on our website, which varies from product specific, through to NMEA 0183 and NMEA 2000 e-Books. We also now have a forum section on our website, which is designed to be a hub of discussion and knowledge for all things NMEA, not just Actisense products.

A closing point that I cannot stress enough, is to ask for advice or assistance when you need it. Marine electronics and devices are expensive and aren’t always straight forward, but anyone who is part of the NMEA is committed to helping others and continually improving the standards and the environment we operate in.

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