Wiring Woes - Never Assume

[redsky49]

As the third owner of my current boat, I occasionally run across "improvements" made by the prior owners. One recent discovery I thought might be of interest to the forum.

I have a small water-cooled heat pump in the forward cabin. I believe that it was installed by the original owner. It was tapped into the 15A Starboard Receptacles circuit, so that simultaneous use of the heat pump (roughly ten amps), and say a toaster (about seven amps) would trip the breaker. The solution, and the correct way to wire this originally, is a dedicated circuit for the heat pump. Here is what I discovered as I was installing a new feed.

Pic #1. This is the added receptacle serving the heat pump. The white cable to the left is the existing starboard 120V receptacle feed, installed by the factory, that serves an adjacent duplex receptacle. The metal handy box and the 20A receptacle were the work of the heat pump installer. Note that the round black cable entering the bottom of the handy box is the feed taken from the last factory duplex receptacle - they used the "pass-thru" terminals at the existing receptacle to piggy-back onto the existing circuit. No strain clamp used on the black cable.

Pic #2. Note the terminals used. These are spade ends, and do not have the mandatory locking tabs required for marine applications. Also the cheap insulation has cracked from crimping and should have been remade.

Pic #3. Here is the empty handy box. If you look closely, you will see the knock-out tab has not been fully removed, just bent inward. If you look back at the prior pics you will see where the sharp edge of the tab would rubbed on the black 120V cable.

Pic #4. These are the terminals used where they tapped into the existing duplex receptacle, and where they connected to the new receptacle they installed.

Pic #5. This is the cable they used to extend the existing receptacle circuit. This is 16-3 gauge. The original receptacle circuit is 12-3, with a 15A breaker. This is a weather resistant flexible cable. It is not boat cable, and the wiring is not tinned.

Pic #6. This is the re-wired receptacle, complete with new dedicated 10-3 boat cable. The bent-over knock-out tab was removed and the box rotated 180 degrees. Proper strain relief is provided at the box entry. Still doing some modifications in this area, so a "work in progress".

I was really a bit taken aback by this situation. First, I managed to ignore this situation for many years as we did not use the heat pump very often. Second, I would have expected a better installation, especially since I think that this was done by a "qualified installer". In addition to the issues addressed above, the routing of the black 120V cable was precarious with no concerns for chafe protection, the use of non-reinforced supply and return hose for the seawater supply, installation of the control wiring (line voltage in this case), routing of the condensate drain, cutting of openings in the bulkhead, etc.

In all, a very poor installation. The take away from all this - don't assume that existing is correct, and that you will frequently not get what you pay for from professional installations.

[redsky49]

Additional pics:

[smac999]

I've more or less found that wiring by factory is normally pretty good. and anything done afterwards by anyone is normally suspect.

[Wotname]

Yes, unfortunately a common story.
FWIW, I personally hate spade terminals, give me ring terminals any day. I get the convenience factor but that is a distant second consideration in my view.

[redsky49]

It was not just the terminals, though the safety ground connection was either loose or disconnected at one of the receptacles.

How the cable did not chafe through at the entry to the metal handy box, I will never know. And the 16ga. wiring used to extend the existing circuit was at risk with a 15A circuit breaker.

Just be careful out there.

[Dave Lochner]

Why is there a metal box on a boat? Especially in a relatively exposed location?

Locking spade terminals can be used safely. These terminals have a slight bend at the end of the forks that make it harder to remove if the screw is a little loose.

The terminals should also be heat shrink terminals.

At least they used stranded wire.

[redsky49]

My personal opinion is that ring terminals should be used wherever possible. The only exceptions that come to mind are for 120V receptacles, where the receptacle terminal screws are captive and cannot be removed to allow a ring terminal.

In the pic below, you can see the receptacle terminals, the green nut at the end for the safety ground connection, and the silver screw on the side for the white neutral connection. These will not fully unscrew, and thus not permit ring terminals. This is a 15A GFCI duplex receptacle, which accounts for the depth of the receptacle.

Below the receptacle is a proper open spade terminal, with the upturned ends that reduce the chance of the terminal falling off the connecting post. This is not a heat-sealed terminal, but a standard high-quality terminal.

While heat sealed terminals are desirable, and certainly indicated in the bilge, exterior locations, etc., I am comfortable using good quality non-heat sealed terminals for most locations. The reason being that heat-sealed terminals utilize a single crimp, while the standard terminals can use a double crimp where there is an additional crimp that helps to provide strain relief. You can always slide some heat-shrink tubing over a standard double-crimped terminal, if needed.

[redsky49]

Regarding heat-sealed terminals, I also include "adhesive" terminals in the same group.

[captainwireman]

I always use an anti oxidant compound such as Noalox and have had great results in side by side experimental comparisons. The proper crimp tool for the brand you are using, the proper place to crimp, wire strip length all are important and easy to do, however, this has nothing to do with the violations here. UL laboratories standards say if the terminal is installed following the manufacturers instructions, it shall exceed the ampacity of a 90C insulation wire rating provided both are UL listed.

[guyrj33]

The adhesive lined, heat shrink terminals I use are double crimp terminals.

[exMaggieDrum]

Those type of household boxes will rust pretty quick on a boat. Should never be used. But even a plastic or wood box should use strain reliefs. In the trades we called such work "ownerizing", which sometimes was done by sub-par installers hired by the owner.

I personally will cut off many ring terminals and replace them with locking spades if it is something I may have to remove and replace more than once - like terminal blocks for bilge pumps. Nothing worse than losing the little brass or tinned screws. They can be hard to replace since they are shorter than you can commonly get at a hardware store. And they can be very difficult to put back on with a ring terminal - a high percentage of them fall off. I have NEVER had a failure from a locking spade pulling off of a terminal, but I do take extra care in putting them on every time. And compression term blocks are OK too provided the screw pushes down on a metal strip rather than the screw only capturing the wire. ABYC approved.

[jmschmidt]

Personally I don't know why the ABYC and many boat owners are so in love with, no they absolutely DEMAND that all electrical connections be by ring terminal. Ring terminals do not provide any better security than does the spade type that has the little flanges on the tips. Ring terminals are a pain in the ass because usually the screw ends up in bilge when you are fumbling (in a seaway) trying to insert the screw into the ring and maneuver the two pieces back into the circuit board or bus bar. Plus the process is slowed down substantially over just backing out the screw and inserting a spade. Lets face it, if the concern is a broken connection due to a loose screw you'll have the same problem with a loose screw and a ring terminal. In fact worse because the failure will be intermittent and more difficult to trouble shoot (again in a seaway). OK, maybe a ring will avoid a short from a dangling wire but proper looming of the wire bundle will usually prevent this.

[mitiempo]

Originally Posted by guyrj33

The adhesive lined, heat shrink terminals I use are double crimp terminals.

Which terminals do you use?

[ramblinrod]

Wait a minute; this changed from "I think"it was a professional installation" to "professional installation sucks" thread.

First of all, there is a big difference between "hired" and "professional" installation. The person who installed this may have been paid , but they certainly were not a professional installer.

When seeking professional installation, you must request to "see" the qualifications of the installer. Any qualified installer will pull the card out of their wallet, that indicates the organization that has certified them. If they can't produce it, they aren't "professional". Expect to pay more for professional installation. If you shop for lowest possible installed cost, you are most likely not getting a professional installation, but rather, the installation you (or the previous owner) paid for.

Ramblin Rod
About Sheen Marine

[Lepke]

I solder after crimping. I'm an old guy that has chased too many problems that turned out to be corrosion between the wire and terminal.
You think you have wiring problems... Try a 73 year old war built vessel that every previous owner just added and deleted circuits without removing no longer used wiring. Metal boxes held together by rust. Each owner using a method unknown to any standards. And then we can talk plumbing.