Yacht Maintenance - Part 6: On-Board Electronics

Modern ships are becoming increasingly hungry for energy as more consumer loads are installed on-board - from lighting, autopilot and refrigerator to increasingly "smart" navigation electronics. It is good that on most yachts at least part of this rapid energy demand is also generated on-board by sun, wind or, indeed, water (wave or tug generator).

Let's start with the batteries, because without them literally nothing works. All should be well if they were kept well charged over the winter and were not stored too cold. However, if they have been discharged too deeply and indicate less than 12 V voltage, they may have been damaged. An indication of damage would be if white-greenish powder settles at the poles. If so, the batteries will evaporate during charging. Then they are done for and and must be replaced. Worse still, replacing only one of them in a battery bank is of little use. Unfortunately, an old, damaged battery drags the others down with it. So it's best in the end to swallow the bitter pill and replace them all at once.

Avoid leakage currents
So-called "wet" batteries must be refilled with distilled water from time to time until the water level is about two or three millimetres above the plates. Of course, this does not apply to gel or sealed batteries. For all types, however, the battery compartment should be clean and dry, especially the top between the poles should be dry - even damp dust or dirt can lead to leakage currents and a constant loss of charging.

If the batteries are in order, we can check the entire on-board system - simply switch on all consumer loads one after the other. When an electrical device does not work, it is very often simply due to the power supply or, more precisely, the lack thereof. Check: Is there any electricity at all? Are all contacts and connections ok? Are the cables intact?

The death of any electrical connection
This applies above all to all "outside lighting" - side lights, masthead light, stern light and so on. They are particularly vulnerable because they are constantly exposed to adverse circumstances: Especially the permanent salt water showers which the pulpit mounted position lights have to endure are, in the long run, the death for every electrical connection. Greenish-black oxidized contacts and rotten cables are the frequent result, and then no electricity will be conducted at all.

Check contacts and connections
So this is what is to be done: clean contacts (best with sanding paper), check all cable connection - if the wires in the cable are already black, nothing will work properly anymore. Cut back the cable until bare wires appear again. Unfortunately, this often means that such a cable (sometimes with considerable effort, if it is elegantly hidden inside the pulpit), has to be extended or replaced entirely. Before doing so, you can of course also check the bulb and hope that only this is broken... that would be easy! Obviously, all lamps in the mast are best checked as long as it's still dismounted and on shore: Take a look at the bulbs, contacts and cable connections!

Voltage tester - your indispensible assistant
A voltage tester or "multimeter" for checking the voltage on board is actually indispensable, but you also need to know how to use it efficiently. Even if it is just one fuse that has blown, it does not happen for no reason. So there must be a problem somewhere, either the device is broken or the wiring is defective. A multimeter helps with the trouble-shooting.

Skipper's favourite toys
Let's take a look at what are ususally the skipper's favourite "toys" on board: navigation electronics. Today, usually integrated into a network of all on-board instruments, the detailed explanation of such systems would go beyond our scope here. Only this much at this point: the winter break and spring before the boat is put back into the water are the ideal time to study the manuals of your navigation instruments intensively. Modern, integrated systems in particular have enormous abilities and options - if you know how to configure and operate them correctly. A computer is only as smart as the person using it. Take your time reading the manuals before casting of the lines!

Autor: Detlef Jens