SEPTEMBER 2017 BEACON

Some time earlier Michigan State University was called to investigate why cows at a certain farm kept falling over dead for no apparent reason. It was found that stray currents through the ground from faulty barn wiring produced a very small current through the ground the cows were standing on and it only takes 2 Volts from the front legs to the hind legs of a cow to interrupt it’s nervous system. It becomes paralyzed, can’t breath or move, and it eventually falls over dead. The farmer wearing rubber sole boots is unaffected. The boys suffered a very similar fate, US Navy divers in a study found that the same 2 Volts AC flowing from a healthy mans head to his legs can paralyze him to the point where he can’t breathe, move, or swim, and if not saved he’ll drown. As we all know, a piece of marine equipment can work fine today and fail tomorrow. Just because you’ve jumped in the marina before, doesn’t mean you can survive it again. A different (and possibly faulty) boat may be docked near you next time. The boys had done it many times before. It should be noted, the battery charger in question on the boy’s boat still worked well as a battery charger, it just wasn’t safe. In the following years, the USPS updated their Marine Electronics course and test in the ‘92-’93 season. Many boat OEMs began installing galvanic isolators and GFCIs as standard equipment, and the issue faded into obscurity. Recent events however have brought it to light again, and the following pages will describe in technical detail the scenario I’ve just described in layman's terms for you. The purpose of this article is to put a complex technical issue into a format the non-technical reader will understand. Here’s the Take Away: If you must swim near a boat in the water; Make Sure You UNPLUG IT, AND EVERY BOAT NEAR YOU!