With the boating season about to kick into gear, some of us are thinking about oil changes, tune up’s, (stocking the fridge, the wine and beer coolers), but what about your electrical system? Have you given any thought to the maintenance or preventative maintenance of your boats electrical system? If not you should, and you should prior to your first jaunt.

Corrosion affects all boats, but those in salt water are more susceptible, and should be checked more frequently. The size of the boat does not matter either, if it has any type electrical system. A fire can be caused from something as simple as a bad connection on a trolling motor.

Your 240v shore power cable is the first part to start. Disconnect it before you start. Check both ends; look for corrosion on the prongs. If you are able to disassemble the plug ends, take those apart, check for corrosion, check for loose connections, and give the screws a check with a screwdriver to make sure they are tight. Check the back side of the plug on your boat for the same things. If you see something that just does not look right, either replace it, or have a qualified electrician check it out for you.

If you have a generator, check the cables or connections to it for the same things. Make sure all connections are tight and clean. Make sure the ground wire is clean and free of corrosion, and has a good tight fit on both ends, the ground could be/is a your lifeline in the event of a malfunction.

If you have an inverter, the same procedures apply, but, pay close attention to your 12vdc side. There is a tremendous amount of current draw on the 12vdc side, and anything that is preventing a good, clean, tight connection is asking for a fire.

From there, occasionally, it is good to remove your boats breaker panel cover, and check there as well. Make sure all screws to the breakers and the buss bars are still tight. They WILL loosen over time due to heating / cooling /vibration. Also look for signs of corrosion or heat. Any place you find some is the potential for a fire. If you do not feel comfortable doing this type of work, consult a qualified electrician to repair it for you.

Your boats 12vdc system is also important, your boat can run without 240vac, but can’t with out 12vdc (most boats). Battery connections should be clean and free from corrosion. There are several products and methods available to prevent corrosion build up on battery terminals, and will greatly extend the life of your cables. Connections from the batteries to the 12vdc systems on your boat should be checked. The same things apply there as do the 240vac systems. Check alternator and starter connections as well.

Safety

Just a few words on safety. Electrical systems are dangerous. Serious injury or death can occur, and occur very quickly. When you service your system, make sure all sources of power are disconnected, and placed in a state that they can not be accidentally turned on while you are doing the work. Disconnect your shore power, isolated your batteries, remove the ignition key. You should ALWAYS test for voltage before touching anything, even if you know it is off, check it anyway. You don’t need to have a expencive meter for this; you just need something that works.

Another point is the 12vdc side. Most people don’t realize that the low voltage side of your system can kill also. Did you know that when a starter is engaged, there can literally be hundreds of amps being drawn from the batteries? It takes only milliamps to kill, the voltage does not matter, it is the amps. Some inverters draw massive amounts of amps while they are running, touch the wrong thing, and it could be the last thing you touch. Use caution and common sense when ever you work with any kind of voltage or power supply system.

Again, if you don’t feel comfortable, or are not sure, ask a qualified electrician for advice or to do the work for you. The small amount of money this will cost you pales in comparison to an injury or death, or to an on board fire caused by a preventable issue with your electrical system.

Cheers

Tony

Go steady T Waka  In 40 years in the marine /auto Electrical Business I have only seen one fatality involving I2 volt/ 24 volt D.C. systems and that was on a High voltage ignition system and the guy had a weak heart. It can cause serius burns however if you wear a ring or necklace and have the misfortune to short these items out across exposed terminals.
Yes be aware but low voltage dc Fatal??  This depends on whether the skin has been pierced or not, otherwise the resistance of the human body (500 Kohms to 1 megohm average) would in most cases reduce the current flow to a few milliamps. But once through the skin layers  the resistance will drop considerably  and the current could reach as high as 90- 100  milliamps, enough to stop the heart.
Thus a 9 volt battery could kill you !!! so remember E=IR

Sorry Tony, I got rather carried away with all that waffle it must be an age thing. probably not right anyway!!!

Seadog  

--Last edited by seadog on 2009-02-23 21:45:49 --

Seadog

This was really posted as an awarness factor and the risk of fire.
But it always surprises me at the beginning of the season how many people have issues with their electrical side caused by basic lack of preventitive maintenance.
And, I was at at a loose end (pardon the pun)when I posted, had nothing better to do.

All the best

Tony