Electrical Don'ts
Well we're finally getting a break in the weather here in Rhode Island and people are beginning to uncover their boat's and start an early spring assessment of work to be done. This made me think about some things you need to be looking for on your boat, today in the electrical area. One of the advantages of being an industry insider is that some of us trade horror photos of things we see. Today I want to share with you one photo that came in from Derek Rhymes, the principle at All Boat & Yacht Inspections LLC, a marine surveyor in Annapolis, MD. This particular photo holds a dear spot in my shop of horrors collection and represents the sort of thing you need to be making sure does not exist on your own boat. Scenes like the one below could be the cause for some truly shocking experiences on board. What you are looking at is a commonly used marine water heater. It is powered by the shorepower system and the power is supplied by the three wires you see in the center of the photo. Black, white and green represent 110-Volt service. Notice how the wires are routed through a stamped out hole on a metal bracket extending outward from the case of the heater. The stamped out hole has no chafe protecting grommet around it's perimeter and let me tell you, the edges of that hole are sharp! The wiring is laying on the sharp edge. What will ultimately happen here is that due to normal vibration on the boat, the edge of the metal is going to chafe through the wire insulation and create a short circuit. If the boat owner is lucky, it'll be a really good connection and trip the circuit breaker protecting the heater circuit. If the boat owner is unlucky, the short circuit will have a poor quality connection and although leaking current directly to the case of the heater, the connection will not be able to carry enough current to trip the breaker. So, the short circuit will just quietly wait for the boat owner to reach down into the locker where the heater is installed. As soon as the boat owner touches the case of the heater. ZAP! Electric shock. The moral of the story here is to visually inspect your wiring system and add chafe protection whenever you see a situation like this on your boat. Don't wait to get zapped!
Well we're finally getting a break in the weather here in Rhode Island and people are beginning to uncover their boat's and start an early spring assessment of work to be done. This made me think about some things you need to be looking for on your boat, today in the electrical area. One of the advantages of being an industry insider is that some of us trade horror photos of things we see.
Today I want to share with you one photo that came in from Derek Rhymes, the principle at All Boat & Yacht Inspections LLC, a marine surveyor in Annapolis, MD. This particular photo holds a dear spot in my shop of horrors collection and represents the sort of thing you need to be making sure does not exist on your own boat. Scenes like the one below could be the cause for some truly shocking experiences on board.
What you are looking at is a commonly used marine water heater. It is powered by the shorepower system and the power is supplied by the three wires you see in the center of the photo. Black, white and green represent 110-Volt service. Notice how the wires are routed through a stamped out hole on a metal bracket extending outward from the case of the heater. The stamped out hole has no chafe protecting grommet around it's perimeter and let me tell you, the edges of that hole are sharp! The wiring is laying on the sharp edge. What will ultimately happen here is that due to normal vibration on the boat, the edge of the metal is going to chafe through the wire insulation and create a short circuit. If the boat owner is lucky, it'll be a really good connection and trip the circuit breaker protecting the heater circuit. If the boat owner is unlucky, the short circuit will have a poor quality connection and although leaking current directly to the case of the heater, the connection will not be able to carry enough current to trip the breaker.
So, the short circuit will just quietly wait for the boat owner to reach down into the locker where the heater is installed. As soon as the boat owner touches the case of the heater. ZAP! Electric shock.
The moral of the story here is to visually inspect your wiring system and add chafe protection whenever you see a situation like this on your boat. Don't wait to get zapped!
