|Three Tips to Maximize Your Electrical Safety|
Location, Location, Location
Location is one of the major keys to a successful real estate sale. You wouldn’t want to buy a house in the southern suburbs if you worked north of downtown. It’s just inefﬁcient.
Likewise in the boating world, location is equally critical. Battery, inverter, charger and load panel locations are fairly ﬂexible. These devices carry the bulk of the current, so they should be positioned as closely together as is safely possible, to maximize efﬁciency.
Imagine if you worked only a mile from your home and had a freeway on-ramp a minute from your driveway. Driving to work would be a breeze! On the other hand, imagine having to navigate daily through ﬁve miles of congested, winding neighborhood roads, and your driving time and ease suddenly become unpredictable.
Any boat owner will agree that in a boat, size is everything. A larger battery bank means more time between charging. A larger charger means shorter generator run times. A larger inverter means less heat generated, and more headroom for additional, plugged in loads. Even more important is the wire size. Just like our roadway analogy, the smaller the wire, the less trafﬁc or electricity that can travel off of the wire without incurring problems.
Best rule of thumb? Ensure that there is less than a 0.25-volt drop across the length of the wire under the worst-case current load. Voltage-drop calculators are available on the Internet but require solid data such as wire size, material (copper, aluminum, etc.), current rating (breaker size) and length of circuit. A 0.25-volt drop is good; a 0.1-volt drop is great.
The third and most important consideration has been saved for last. Never forget that a loose connection requires that the current ﬂows through only the touching parts. Like pesky potholes in the road that can cause swerving, jarring and potential damage, loose connections require that current “dodges” the bad connections and ﬂows down a restricted path. Loose connections cause higher resistance, higher voltage drops and extreme heat that can easily spark a ﬁre.
Another loose connection consideration involves the inappropriate usage of wire nuts, which are expressly designed for single strand residential usage. When applied improperly in a boat, this application can cause the threads of the nut to literally cut through the ﬁne strands and ultimately create a weaker connection with less integrity than using crimped butt splices, or solder and shrink tubing.
Another red ﬂag is an accumulation of corrosion around the wiring, especially where there are connections or copper. Appliances rated for marine use should have conformal-coated circuit boards to prevent corrosion. Likewise, any battery connections or exposed material should have some type of protective coating to prevent gases or salt mist from causing corrosion, which would eventually seep into the connection and restrict current ﬂow.
Finally, besides these simple tightening and cleaning protocols, be sure your electrical systems checklist calls for a review of water levels in batteries and a system check on your inverter/charger systems.
Three easy tips…all designed to maximize your time and fun on the water!
Tech Doctor Don Wilson has worked in technical capacities in the marine, automotive and recreational vehicle (RV) ﬁelds, and for the military since 1989. He has extensive experience in designing and troubleshooting onboard electrical systems. A former customer service manager dealing with electronic issues, Wilson currently serves as a technical instructor for the Recreational Vehicle Industry Association’s Trouble Shooter Clinics and is a full-time sales application engineer for Xantrex Technology, Inc.