Warning & Safety Reminder !!!

[Maine Sail]

Hi All,

Winter is coming so please take the time, and spend the money, to do this fix/upgrade!

So here we were victorious in our "first to finish", with a solid 5 boat lead mood, when all of a sudden a call from below of smoke?

We had no sooner crossed between the committee boat and the mark, and fired up the Japanese genny,when one of the crew says, in a rather nonchalant manner, "hey there is some smoke down here?" The skipper, a rather quick thinking one, immediately kills the engine and we pop the genny back out, while at the same time calling for a shut down of the battery selector switch.

Within seconds the smell of an electrical fire is filling the cockpit and the cabin looks like a Cheech & Chong movie only it doesn't smell quite as good..

I grabbed the helm and the the skipper goes bellow and begins digging into things. About 20 minuted later he pops his head up with a 24" long piece of bare 14 gauge SOLID copper wire. In my usual sarcastic way I chuckle and say, "see solid wire has no place on a boat!!"..

Unfortunately I had no idea how wrong I was! That 14ga SOLID copper wire had been 14ga tinned multi-stranded wire with a jacket just minutes before!!

Never in my 35 years of sailing have I seen a two foot long piece of multi-stranded wire turned into a piece of un-jacketed solid copper so fast!!

Now I know the "alarmist crowd" will be out in full force on this thread but let me assure you this boat, it's the "red boat" for those in the know, is kept in pristine mechanical and physical condition. This is not a boat that is left to chance on ANYTHING and the owner spares no expenses keeping her up!! Those who know this owner know exactly what I'm talking about..

So here's the safety reminder!!!!!!

FUSE YOUR BATTERIES AS CLOSELY AS YOU CAN TO THE BATTERY POST!!!!!!!!

Here's what we found. The ground lead for the metal cigarette lighter was a female quick connect. It looked just like the quick connects in the picture below and it somehow came disconnected.

When it did it began swinging into the stud for the house bank on the back of the battery selector switch! OUCH!!!! Who said there is NO vibration on boats? I'm sure the "no vibration on boats" crowd will be commenting at some point.. Remember this wire went straight to the ground buss and was rubbing the battery selector switch terminal post a direct ground short of the worst type!

Eventually it hit hard enough, possibly aided by the vibration caused from starting the engine, to literally weld itself to the stud and then turn the wire to a solid conductor! I'm not kidding when I say that I could not decipher this wire from a piece of Romex used in house wiring. There was no physical sign of any stranding left anywhere and no sign of any tinning either. this wire got so hot there was not even any residue left from the melted jacket just BARE copper..!

Luckily this was only a 14ga wire and it actually blew like a fuse after it thankfully got hot enough. A fuse at the battery post such as a ANL type like the one below would have stopped this ground short in about a nano second!!:

Unfortunately, this fuse block is one of those items the owner had been "GOING to add" but as boats go it kept getting further and further down the "to do list" as other chores and projects piled up... We all are guilty of this type of mistake!! "Oh I'll get the flares on the NEXT trip to West Marine..."

So what have I learned?:

#1 Be very, very, very careful using "quick connect" terminals on boats! If you MUST use them use the fully insulated style and NOT the un-insulated ones!!! EVEN ON GROUND WIRES!!! They look like this:

#2 You should make every effort protect the studs on the backs of battery switches or ANY other large amp cable terminals with post caps!!

#3 Any wire in the vicinity of HOT terminals needs to be secured so there is NO WAY, even if it came disconnected, to touch a HOT component. Zip ties are CHEAP!! This wire was zip tied within 6" of the cigarette lighter but it was still not enough to prevent it from falling onto the battery post!!!

#4 And finally the MOST important component is that ALL battery banks MUST have a fuse as close to the battery as possible!! ABYC suggests 7" but I know mine are about 9" to 10" of cable run as it is the closest I could get them..



DO NOT wait to fuse your batteries, or move it down the list, behind those new fitted v-berth sheets you've been craving!! If this has been on your list please, for your own sake, MOVE IT TO THE TOP!!!!!

BTW the post this wire came in contact with was the direct to the battery and even turning off the switch DID NOTHING. The only way we prevented a fire was because the wire melted in half and acted as a fuse because it was a light 14 gauge run . If this had been a 10 gauge wire, for say the macerator, we may have burned the boat to the water line.

Think about it!!!!!


Call me an alarmist but if you witnessed what I saw you'd have been buying fuse blocks TODAY!!!

This is an easy install:

 

[Don S/V ILLusion]

Excellent suggestion MS. Can't help noting that the battery terminals are uncovered in the photo which is contrary to conventional standards but I am sure you ordinarily have things well covered.
Reminds me of a strange encounter I once had aboard someone else's boat with the USCG who stopped us for an inspection. Fortunately, they were more concerned with safety than paperwork when they sited the owner for not having properly covered battries and ignored the fact the boat was unregistered.

 

[Bob Poff]

Fuses are cheap safety

It seems we'll go all out on some items on our boats but sometimes miss these simple things.

And how often you find that someone put a fuse at the "device" end of the wire.
Keep it close to the battery. The fuse is to protect the wire not the device.

In my research on house batteries I read a review on a manufacturers site speaking of how one of this fellows paralleled batteries shorted.
The interconnecting lead between the rest of the bank went up in flames.
I'm even considering fusing those leads.

 

[Ralph Johnstone]

................. what is the amperage rating of the fuse at the battery bank (same as the house main breaker) ? And thinking of that, what would the rating of the fuse at the starter battery be considering the large draw of the starter motor ?

 

[sailaway78]

A little disagrement

Mainesail,
While I agree totally in the premise, and that the battery should be fused as close as possible to the battery, I kind of doubt that would have helped in this particular situation. You would need a battery fused at 100 amps or so, to carry all loads, such as starting. A 14 ga wire, fused to a 100 amp fuse, would do exactly what that one did, and would be melted down before blowing the big fuse, if it even would blow it. Each circuit should be individually fused, with a proper sized fuse. A 20 amp. fuse in that lighter circuit would have blown instantly. I don't think a 100 amp fuse would have made any difference. There are fuse blocks available pretty cheap, that you can run individual circuits to, each one fused the proper size. Or an inline fuse will work also. But you are spot on about protecting the circuits, and making sure that wires can't come off and short out.

 

[Don S/V ILLusion]

Mainesail,
While I agree totally in the premise, and that the battery should be fused as close as possible to the battery, I kind of doubt that would have helped in this particular situation. You would need a battery fused at 100 amps or so, to carry all loads, such as starting. A 14 ga wire, fused to a 100 amp fuse, would do exactly what that one did, and would be melted down before blowing the big fuse, if it even would blow it. Each circuit should be individually fused, with a proper sized fuse. A 20 amp. fuse in that lighter circuit would have blown instantly. I don't think a 100 amp fuse would have made any difference. There are fuse blocks available pretty cheap, that you can run individual circuits to, each one fused the proper size. Or an inline fuse will work also. But you are spot on about protecting the circuits, and making sure that wires can't come off and short out.

My understanding of his description is that the gnd wire shorted directly to the battery post in which case, a fuse (typically placed on the hot side of the circuit) would have been useless. Did I misunderstand?

 

[sailaway78]

Your right

Don,
Your correct that it was a ground to the battery terminal. Didn't read correctly. Maybe I was too anxious to find an error in the post. Wouldn't that be a first, to find an error in one of Maine's posts. But my main premise was that I don't think a 100amp fuse at the battery would have prevented a 14 ga wire from totally melting. 14ga wire, just will not handle 100 or so amps. I try to avoid any terminal that isn't screwed on. Not always possible. But again Maine is correct. Zip ties are cheap, and easy to use.

 

[Fred Ficarra]

Re: Your right

And when I rewired my boat there was no practical way to fuse a starter cable, so it wasn't required by "those guys", ABYC, at the time. But now Blue Seas has come up with a series of high amp breakers so the protection for high load wire is possible now, but I don't know if it's required yet by ABYC.

 

[ITMaster]

some of my circuits that I have on board use that same style of fuse block and I have one in particular that is going to my inverter that is 400 amp rated. I think that the point Maine Sail was making was the use of the spade to female quick connector.

I thought that I read in one of your posts Maine Sail where you indicated to use butt connections with heat shrink or a lug connector mounted with a screw to a terminal bar instead of the spade male to female quick connector connections though, didn't I? I don't use any quick connectors, and this is another good reason to not smoke and have an electric cigarette lighter, which I don't.

Gald you all were lucky and there was no fire aboard.

While we are on the subject of fire, this is as good of time to put out a reminder for everyone to do a spot check of your fire extinguishers. Check the guage and ensure it is in the green zone, that it isn't over 5 years old, that the pin is installed and there is a safety strap on it, that the hose is in good shape and not cracked and turn the bottle upside down and tap with a rubber mallet to unpack the bi-carbonate that has settled and packed to the bottom. Just tap the bottom of the bottle several times with it upside down and then shake the bottle back and forth several times to mix the bi-carb back up some.

If the bottle is over 5 years, it should be hydro-tested; it is just as cheap to replace as to run the hydro-test since that involves disassembly and putting under pressure and then refill and reassembly. Just as cheap to go with a new bottle.

 

[Maine Sail]

very good points!

I thought that I read in one of your posts Maine Sail where you indicated to use butt connections with heat shrink or a lug connector mounted with a screw to a terminal bar instead of the spade male to female quick connector connections though, didn't I?

I suggest those methods when you can utilize it. Unfortunately there are many marine products still sold that use bullet or spade type quick disconnects like the cigarette lighters.

I don't use any quick connectors, and this is another good reason to not smoke and have an electric cigarette lighter, which I don't.

I don't smoke either but I do need to charge my cell phone, hand held VHF, plug in my search light etc. etc. The cigarette/12V socket has many uses.

Gald you all were lucky and there was no fire aboard.

Thanks it certainly could have ended differently but we got lucky..

While we are on the subject of fire, this is as good of time to put out a reminder for everyone to do a spot check of your fire extinguishers. Check the guage and ensure it is in the green zone, that it isn't over 5 years old, that the pin is installed and there is a safety strap on it, that the hose is in good shape and not cracked and turn the bottle upside down and tap with a rubber mallet to unpack the bi-carbonate that has settled and packed to the bottom. Just tap the bottom of the bottle several times with it upside down and then shake the bottle back and forth several times to mix the bi-carb back up some.

Excellent reminder!!!!!!!!!!!!!

If the bottle is over 5 years, it should be hydro-tested; it is just as cheap to replace as to run the hydro-test since that involves disassembly and putting under pressure and then refill and reassembly. Just as cheap to go with a new bottle.

During the boating season Wal*Mart has great prices on the same exact Kidde extinguishers that WM sells...!

On a more interesting note:

ABYC E-11 states "ring" or "captive spades". Safety or "captive spades" have the up turned fork ends...

ABYC = "Terminal connectors shall be the ring or captive spade types.” 11.16.3.4."


So I guess that makes the vast majority of 12v cigarette lighter sockets, like this one, NON-ABYC compliant as the grounds are usually a quick connect not a captive spade or ring..???

 

[Ross]

Mainesail,
While I agree totally in the premise, and that the battery should be fused as close as possible to the battery, I kind of doubt that would have helped in this particular situation. You would need a battery fused at 100 amps or so, to carry all loads, such as starting. A 14 ga wire, fused to a 100 amp fuse, would do exactly what that one did, and would be melted down before blowing the big fuse, if it even would blow it. Each circuit should be individually fused, with a proper sized fuse. A 20 amp. fuse in that lighter circuit would have blown instantly. I don't think a 100 amp fuse would have made any difference. There are fuse blocks available pretty cheap, that you can run individual circuits to, each one fused the proper size. Or an inline fuse will work also. But you are spot on about protecting the circuits, and making sure that wires can't come off and short out.

You can check the tables that I have linked in the past but 16 AWG copper fuses at 114 amps. 14 AWG would be somewhat higher. There is little that can be done to protect against this sort of event except supporting the wire to prevent it from going adrift.

 

[Tim R.]

If you have not guessed by now, I am the one with the smoking gun...er, I mean boat.

Here's what we found. The ground lead for the metal cigarette lighter was a female quick connect. It looked just like the quick connects in the picture bellow and it somehow came disconnected.

Athough Maine Sail's story is very accurate, he gave me a little more credit for not being an idiot. I had been in the panel the week before and had found that the ground wire had come loose and forget to reconnect.

This winter I will be rewiring my entire panel with all new breakers and indicator LEDs. There will be terminal bars screwed into a sheet of glassed marine plywood inside the panel and then a loom of cable running to the newly hinged panel similar to the photo from this ericson 34 brochure. This is how Pacific Seacraft wired them after they bought Ericson. Notice the sheets of acrylic protecting the terminal bars and breakers.

Maine Sail, check out the trim around the panel opening. This might be a good way to give your cutout a finished look. No need to match the grain either.

 

[newly anonymous]

while you're at it...

...if you use the large-amperage Class T battery fuses you might want to carry a spare. I blew one last summer while installing a wind turbine, and was surprised to discover that I didn't have a spare on board. Of course, it's a $53 fuse at WM, which is a bunch of change to shell out for a spare you never hope to need, but in talking with the usual suspects who gather at the yacht club around 1700h every afternoon, I was further surprised that no one had an extra Class T fuse on board.

Glad I didn't discover the lack of a spare during a passage offshore.