Lighting – Incandescent to LED

Last year when we purchased the boat I noted the lamps were all incandescent aboard the vessel.

One thing I resolved to do was to change out the lamps for LEDs.  While I prefer incandescent lighting to LED or fluorescent, due to the wavelengths being better on the eyes the amount of energy used by the former is significantly less than any Edison type of bulb.  Although the government in their… “infinite wisdom” forced the public to switch from the safe incandescents to “Compact Fluorescent Lamps” (CFLs) I hate those things.

CFLs are dangerous.  They contain mercury, phosphorous and electronics inside the bulb base.  Although they do use a little less energy, they still draw a hell of a lot more power than LEDs do and the light wavelengths are worse on ones eye sight than are incandescent bulbs.  For those who are so environmentally aware, why didn’t you fight those CFLs before hand because they have a LOT of poisons that go right to the dump sites.  But, that’s none of my business.

The lamps are a standard type of lamp fixture.

Typical lamp fixture aboard Adventure

Typical lamp fixture aboard sv Adventure

The fixture above contains a single, bayonet base 12 volt dc (VDC) socket with two wires and pins at the bottom inside of the socket as shown below.
Inside a lamp fixture

The wires are tied to a positive (+) and negative (-) line coming from the breaker panel or a buss feed (a buss is a block with a heavy positive wire and then fed to various locations, usually controlling one area on the boat by one breaker).

The problem I ran into was the bulbs I chose to use, which I will explain.  Instead of spending $40 on West Marine replacement lamps which I find exorbitant costs.  Do they work any better? No, I tested them.  I went to Walmart and my wife ran across car LED lamps.  On the WM and other replacement bulbs the two pins on the base of the bulb are + and -.  The car bulbs however, aren’t.  The bayonet base is the negative and each of the two pins are positive.  One is the bright and one is the dim, so in the car when you hit the bright switch, all the LEDs on the bulb come on.  On the dim side, only a few of the LEDs come on.

LED car head lamps from Walmart

Comparison of LED (Left) and incandescent (Right)

So, I had to rewire the lamp fixture.  Since none of the lamps are mounted anywhere there is metal (and therefore not grounded to the electrical system in anyway) it was pretty easy to simply make the lamp shell, the metal part holding everything negative.  I tied the negative wire to the metal casing using the existing hardware, and by placing crimp connectors that would fit under the screws.

Since the wires were shorter than they should be, I made some short pigtails to assist in the connection to the casing.

Unfortunately, I ran into a lot of wiring issues, and some of that is pictured below:


What we’re seeing are multiple wires attached to the same point.  Given that I didn’t have time to rewire the entire boat while working on this, I didn’t do a great job and simply kept things as they were, extended wires and re-built many of the connectors (like the one you see now, which was feeding more than one lamp in the galley).

Basically, the lamp circuit consists of a switch, a lamp socket, the lamp itself and a + and – wire wired in series.  It’s very simple but I’ll draw a schematic later for those that are interested and add it to the document here.

One problem I ran into was not having extra lamp fixtures.  And at least one of them was badly damaged from water leaking into it.  I tried cleaning the “lens” which is the brass fixture, shaped like a concave lens to help shine the light out of the back of the fixture through the glass.  Here’s what I wound up finding and the temp fix until I can purchase some replacement lamps.


Corrosion inside the fixture.

This fixture was situated over the galley sink and seemed odd, so I opened it up and found it full of water. I’m surprised it had not failed sooner. So I tried polishing it up and wound up with this:

Obviously, it did not polish up well. Thinking quickly, I ran to one of the drawers and obtained a shiny substance that naturally occurs in the galley…. Aluminum foil. I wired it up, installed the bulb and added some of that cool stuff I can only find in the kitchen 🙂

My wife never noticed the missing materials. I think…. I then reassembled the lamp and reinstalled it.

And this is what they look like turned on:

The LEDs are pretty bright, but you have to work with a meter to determine which of the two pins on the bottom of the bulb is the “Bright” one and make sure that’s the one wired to the circuit.  You need to make sure your crimps are tight and you have a good electrical and mechanical connection, because one without the other is no good.  I didn’t do any soldering here, as it was not needed.  I also did not rewire the entire boat with new wiring (which needs to be done but that was not a project for that weekend).

I have not completed rewiring all the lamps, I still have about a dozen of them left to do.

I also did not rewire the reading lamps in the aft cabin and instead spent the money on replacement bulbs because I didn’t have an easy way to rewire the lamp sockets and fixtures.  In other words, I DID spend a lot of money on some of the lamps (and I didn’t get them at West Marine, instead I purchased them at discount from a local marine store near to my marina in Norfolk).  When I get the chance in the next week or so I will be visiting Batteries Plus because, guess what? They too sell standard LED lamps and I’ll price them out there as well.

The test for the lamps was against the ammeter built into the power panel.  The incandescent lamps individually were drawing almost a full ampere of current.  I turned off everyting in the boat, flipped on one lamp, measured the current and did some calculations.  The lamp drew .9-1.0 amps at 12.8vdc.  Watts Law says that current (I) X voltage (E) = Power in Watts (W)

P = I * E

P = .9A * 12.8V

P = 11.52 W

That’s a lot.

The LEDs drew nothing readable.  But they are marked on the packages at .22A.  The meter didn’t even move (it’s analog, so I don’t have a digital meter there and didn’t really have the time or inclination to put my digital meter in series in the circuit).  Knowing what the package says we can do the math:

P = I * E

P = .22A * 12.8V

P = 2.816 W

About 20% of what we were using before.  I’d have to turn on five LED lamps to come close to drawing the same amount.

This article will be placed as a “page” on the blog so it remains there in perpetuity… or for a long time anyway, and I’ll link it on the main page for folks to see, then they can look it up later.