Here's a solid overview of electrical safety onboard

Posted by Glcc Office
 December 4, 2024

Introduction of Electrical Safety article by Mark Lifter

Most of us boaters are aware of the dangers of boating electrical systems. Sometimes we learn things the "hard way".  Those occasional shocks can hurt, and at times be dangerous.   Perhaps more likely than concerns about danger,  we may feel that we need a bit more knowledge and guidance about maintaining and monitoring the health of our electrical system.

 Electrical systems on sail and power boats can range from the simple to very complex.   With larger and more modern boats with increased electrical demands, devices and other equipment , the systems lean heavily toward complexity.   Given this, boaters often depend on qualified marine electricians to solve problems and do more complex installations.  Others are comfortable with their knowledge of what and how to do all things electrical.

This article on Electrical Safety from our friends at Ocean Navigator Magazine provides 18 recommendations (or reminders)  in such areas as: what to watch out for in your electrical connections and components; using Ground Fault Circuit Interrupters (GFCIs); the importance of circuit breakers and not overloading them; the need to assure all systems are grounded; keeping contacts dry and safe; monitoring wiring connections; and more.

For those interested in a deeper drive into marine electrical issues and safe practices, consider:

       *Boatowners Mechanical and Electrical Manual, 4th Edition by Nigel Calder

       *Boatowner's Illustrated Electrical Handbook by Charlie Wing

Also note that GLCC members can receive a free digital subscription to Ocean Navigator Magazine here:  

May the (electrical) force be with you...

Electrical Safety by Rob Laymon in November/December 2024 Ocean Navigator

 

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Hi Bruska,

Interesting story and good catch on the grounding wire. That had dangerous potentials. Think how many installs have details left out or “deemed unnecessary” by the installer on boats out there. On Alchemy, the grounding wire is installed properly, so it is something in the internal wiring of the inverter that trips the very sensitive GF levels, so just disconnecting has worked for me.

Do you know what the tripping levels are for Michigan marinas?

That is an interesting stipulation I have not come across before: requiring professional installation for a warranty to be effective. What brand of inverter was this.

I think a case can be made that for many boat related projects, a conscientious and handy skipper may do a better job than a randomly assigned boat yard worker. We will know we are unsure of what we are doing and are likely to pay close attention to the gear’s instructions. And where confused, one can get a consult and help. And we are not under time constraints. For, example, all terminal crimps on Alchemy have a coating of copper-loaded conductive grease painted onto the strands: something an employee whose boss is watching the clock will not take time to do. (may be over-kill in fresh water, but not in a salt water boat).

At minimum, I recommend being there whenever work is done. In this way, I learn a lot and can be a “surgical assistant” to the work handing in tools to awkward positions, getting a coffee, but also closely observing the work. I have asked a worker who asked me to leave him alone to do a job, to not continue the work. We found a reasonable compromise.

My best, Dick Stevenson, s/v Alchemy

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I had an inverter issue where it was the cause of tripping the dock's ground fault both at my home port and several Michigan municipal marinas.  I had the yard remove it and I took it to the authorized repair facility for my brand.  They tested the unit, it was fine.  

I inspected the boat's wiring and found the inverter's case ground was never attached.  Since then, the inverter and the dock's ground fault have been working fine.  As I travel, I have not had any further tripping of any dock's ground fault.

As an aside, when it was initially installed, it was incorrectly wired and would not operate.  I was a little peeved as when the original installation was done, I laid out the appropriate wiring page of the manual for the installer.  After they corrected the incorrect wiring, the unit worked.  When my marina upgraded the dock wiring, it, then, would trip the dock's breaker.

I would have installed it myself, except the warranty specified it must be "professionally" installed.

Two points:

1. The State of Michigan has aggressively moved to much tighter ground fault levels.  In response to concerns about electric shock hazard on the Great Lakes.

2. I agree not all the boat yard help is competent. 

 

 

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Hi all,

There was recently a recommended article on electrical systems safety which was, indeed, quite good. A couple of additional thoughts.

In the Great Lakes, I have found, that the levels necessary for tripping ground fault on marina pedestals to be quite strict: probably appropriately so.

I have been in a couple marinas where a boat has come in and plugged-in and the whole dock/pontoon goes off line. On two occasions, I have done very casual over-the-shoulder consulting and suggested disconnecting their inverter’s wiring to the AC grid: easier on some designs that others.

In each case that has solved the tripping of the ground fault and allowed them to plug-in.

I suspect that there is something in the internal wiring of some (all?) which signals a ground fault: perhaps when none exists??

And while the inverter wiring is being worked on, consider putting a simple A/B (on/off) switch in the DC cables from the battery bank to the inverter. In this way, when working on AC wiring, if the inverter is left “on” the worker is protected from shock.

This goes double for the more modern inverters which, when left in a stand-by mode, can sense demand and bring AC on line in a surprising and lethal way to the un-way worker.

And, the article suggests a qualified licensed electrician be hired for AC work. I am far from an expert in this area, but the only licensing I am aware of is for land based electrical work. And, again it is my take, that a land-based electrician should be versed in the differences a boat’s AC system demands before work being done.

The closest I know of ensuring competent work is someone who has been certified in marine electrical work by ABYC (American Boat and Yacht Council) and adheres to ABYC standards. I always ask.

And, a word of warning: too many boat yard workers who are assigned electrical work have learned on-the-job assisting another employee until sent out on his/her own. This is a terrible way to learn. There is always the job being timed and the goal is the job being done in a timely fashion rather than the training. And the trainer likely learned the same way.

And, there is a big difference in danger to worker, the crew and the boat from DC vs AC systems.

My best, Dick Stevenson, s/v Alchemy