Electronic prime directive #1: Take care of your boat's electron source, no electrons = no electronics!

In today's computerized age of networked electronic systems representing a veritable alphabet soup of acronyms (GPS, ECDIS, AIS, VHF-DSC, ARPA, GMDSS-to name a few) it is more important than ever to make sure that your boat's electrical system is in good working order. Electronics thrive on good clean power. Problems such as voltage surges, sags, transients, and momentary interruptions can cause system failures. The best way to protect vital electronic loads from temporary bad power glitches is with a good old uninterruptible power supply (UPS). There are even power strips available from computer companies that can help protect your PC. Although the power strips are very small and take up little room, there are other more rugged and much larger UPS systems that can be found in places such as an engine compartment, pilot house, or radio console. These larger units have internal batteries and much more complex electronic control circuits than the power strips. These you will have to keep an eye on by periodically checking the status LEDs.

Whether we are talking about your boat's alternating current (AC) or direct current (DC) power system there are a few golden rules that a boat owner can follow to help protect both the electrical system of his vessel as well as the various electronic loads being supplied by it. I suggest that the owner periodically check on the following conditions of electrical connections and make sure that they remain dry, clean, tight, and vibration free. I suggest that the following checks and or adjustments be made without power present in any form, a pre-lighting off check.

Keep it dry – The importance of this one should be obvious. Moisture of any kind tends to degrade electrical equipment/circuits causing grounds and in the extreme causing catastrophic shorts. If you detect moisture then wipe up the major amount with a clean rag until it looks dry and then take a heat gun or blow dryer and finish the job by playing the hot blast back and forth where the moisture was. Be careful with the heat gun and don't overdue it or you may fry an electronic circuit or component. I usually keep the nozzle a couple of inches above the board and keep it constantly in motion for about a minute or two. Keep touching the board to make sure that you are not overheating it. It should feel hot, but not painful to the touch. Radio frequency (RF) connectors are especially susceptible to becoming moisture laden, especially topside RF connectors. When this happens, the signals become so attenuated as to be down in the dirt and useless. More than once I've had a multi-million dollar microwave communications system go down due to connector moisture, where the solution was to disassemble the connector, wipe it dry, and then use the old heat gun trick to finish the job.

Keep it clean – If chemicals, dirt, or grime are allowed to build up on electrical/electronic equipment, then you are certainly in for some trouble. Certain chemicals such as battery acid can cause extreme corrosion to the point of eating away conductors. The accumulation of dirt or grime can compromise your electrical system by causing creepage, grounds, and even direct shorts. You can use a clean rag with some warm water to clean electrical equipment with and then finish up by wiping with a clean dry rag. It is especially important to keep high voltage or high frequency equipment clean. 

Keep it tight – This is really important because loose connections cause excessive current draw that can not only fry your valuable and expensive electronics, but can also cause electrical fires. We don't even want to hear the F word (fire) aboard our vessels much less have to contend with one that could have been prevented in the first place. Check all connections including the electrical receptacles that are mostly taken for granted. These will have to be replaced if they become excessively loose. Be careful when tightening screw type terminal lugs on terminal strips, tighten the screw until they are snug, but don't over torque them or you may break off the screws.

Keep it vibration free – This may be one of the hardest things to control onboard a sea going vessel, but it is mentioned because it too is an enemy of electrical/electronic systems. Vibration can cause circuit board bending, solder connection stresses, and component failures. The best way to deal with vibration after making sure that all prime movers are running smoothly and all rotating machinery is as balanced as possible is to try and mitigate against the effects of vibration. Use isolation mounts on all equipment boxes mounted in high vibration environments. Use lock washers on terminal strip screws that suffer from excessive vibration, silicone RTV (room temperature vulcanization) can be used to help maintain and protect electronic connectors from excessive vibration. After the connector is secured by hand then cover it with RTV which also tends to seal out moisture and dirt.

Before we wrap up our discussion on the importance of keeping our power system optimized and the golden rules of electrical equipment, I want to mention a small connector that is becoming ubiquitous onboard all size vessels, the RJ-45 eight pin, insulation displacing connector. On land, this connector is often used for connecting ethernet networks. It is important for boat owners to be able to check RJ-45 cabling and also to be able to reconnectorize a bad RJ-45 connector. My next installment of this newsletter will specifically deal with this important issue. I once observed a fellow radio officer aboard a modern cruise ship wiggle a bad RJ-45 cable that was obviously defective in order to get the C-band satellite communication unit to work. He should have changed out the cable or at the very least reconnectorized the bad end. So you see that even the big boys are having some trouble with the RJ-45. 

 

Fredrick Gary Hareland holds an AAS degree in rescue and survival operations and in avionic systems technology and is a certified marine electronics technician and NARTE certified telecommunications technician. He has served in the U.S. Navy, Coast Guard, the Military Sealift Command-Pacific and has worked for Maersk Line Limited and Norwegian Cruise Line. Hareland currently works at China Lake Naval Air Warfare Station as a microwave-communications technician. He lives in Ridgecrest, Calif.

 

By Ocean Navigator