On a recent episode of "Deadliest Catch" (A Discovery Channel series about Alaska Crab fishing, airs at 5 and 8pm Pacific time) one of the vessels experienced a serious electrical failure. Apparently a breaker in the main distribution panel failed, causing total power loss which tripped the main breaker. The crew located the problem in the panel by first finding the "burning smell" then proceeded to reset the main which caused an arc flash (luckily for them behind the deadfront!).

They removed the defective (?) breaker and tehn reset the main again which held. Once they had full lighting again you could clearly see the flash damage to the panel interior.

Several things about this incident caught my attention:

1) The crew did not seem to be too aware of the real danger of standing too close to a faulted panel while resetting the main breaker. (Of course, the real issue for them was the possibility of sinking as the vessel could not move without power.) Luckily the arc flash was "small" as I'm sure that the size of the vessel's generator limited the availble fault current.

2) After restoring power there was a lot of poking around with the deadfront removed.

3) The PPE consisted of their wet raingear and fishing gloves (yikes!)

4) The panel was located in a passage directly off of the main deck, roughly 10-20 feet from the hatch, protected but still looked like it could get wet. It did not appear to be a NEMA 3R can.

5) With the stuff piled in front of it, who needs working clearance?

This episode should re-air at 5pm Pacific time on June 7th if you'd like to check it out.

Now for the questions for our experts:

1) Are there special breakers made for marine applications? The breakers appeared to be standard "H"(?) Frame types, (GE/Westinghouse) similar to those I've seen in cinema main panels.

2) Same idea in regards to panels. I would think that constant exposure to salt water mist/air would require special materials to hold up.

3) Is there some sort of equivilant to the NEC for ships?

"Deadliest Catch" is an interesting show overall, I was amazed at what those folks go through to catch some crab. The stakes are high, it is dangerous and backbreaking work, but the payoff is also high. In the first part of the series, the "King Crab" season, each crew member of the vessel catching the most crabs walked away with over $8,000 EACH for three days of fishing!

NEC 90.2(B) Not Covered. This Code does not cover the following:
(1) Installations in ships, watercraft other than floating buildings,
railway rolling stock, aircraft, or automotive vehicles
other than mobile homes and recreational vehicles
FPN: Although the scope of this Code indicates that the
Code does not cover installations in ships, portions of this
Code are incorporated by reference into Title 46, Code of
Federal Regulations, Parts 110–113.
http://www.ul.com/marine/

Here's a couple of recollections from a ship (actually an SSN) my US Navy days in the early to mid 70's.

As noted above, the NEC does not apply, but then again, the fire insurance companies that created the NEC in the first place did not cover us either.

From my limited experience, shipboard electrical systems are not in the least similar to building electrical systems. The biggest difference is that our systems, even the 120V systems, were all ungrounded. This is difficult for most electricians to understand, but it was necessary. If any phase became unintentially grounded, it would have no effect as long as the ground was detected and cleared before another point in the system became grounded. We had permemant ground detection equipment to monitor the condition of the electrical systems.

Radar

Today I learned that UL has a separate listing for "naval use" breakers.

An update:

On the final episode, the SAME vessel lost all power again!! Although it wasn't too clear why, it seemed that the main generator's fuel filters became severely clogged. As they made thier way down to the engine room, some sort of alarm was sounding.

But it all ended ok for them anyway, their total catch was good and each crew member got around $13,000 for five days work. Top catching vessel got about $27,000 per man.

Anyone for some crab fishin'?

I look foreward to catching this show on satelite tv eventually. Meanwhile, I'll fish 'em out of a tank in the supermarket, it's safer if less remunerative. They even tape their claws up so you don't get nipped!
Alan

Apparently this was the last year for "derby" style crab fishing, where the goal is to catch as much crab as you can before the season closes, which is determined by fish and game based on total catch, and rate of catch.

Next year, quota will be to each boat allocated based on their past catches, so the chance for a big payoff is no longer there, unless you get assigned a large quota.

The down side is that during the first 24 hours of the season, one boat, and at least 6 fishermen were lost at sea, making Alaskan crab fishing one of the deadliest jobs in the world.

The partner boat for the lost vessel, despite losing 12 hours to SAR efforts, pulled in a record catch.

The season started with 176? boats, with 6-8 crewmen per boat.