tanzer22.org / 2104 / Electrical / LED Lighting

On a sailboat, amp-hours are a jealously guarded commodity. Ok, what's that in English, for those who don't speak Manager?

In simple terms, your battery will power a given size of lamp (in Watts) using a given current (in Amps) for a given time (in Hours). If you can maintain the light output, while decreasing the current, then it's almost as if you're getting something for nothing.

On Brave and Crazy, I just installed 14 LEDs. Six high-intensity white, and eight high-intensity miniature red. With all the LEDs turned on, they use 1/20th the current of the halogen lamp in this photo:

Now mind you, they don't produce as much light, but I find it's more than enough to see what I'm doing.

Construction

This was the really tricky part of the install. On the pop-top T22, there is a wood surround that extends most of way into the cabin. I took advantage of this to mount most of the LEDs.

For the cabin proper, I recessed the two white LEDs into the grab handles. These are installed on the v-berth bulkheads, so that they fall to hand as you make your way forward. The LEDs shine on the headliner, providing indirect light.

As you can see from the photos, the angles are very particular. I had to drill from the top and back of the handle, so the holes meet in the middle. This made it possible to install the LED completely blind, so there's just a little clear dome poking out. The wire is completely hidden behind the bulkhead.

Installation

V-Berth

Two red LEDs are embedded into the wooden support rail at the head. I used a router to make a groove for the wires. The red goop you see on the wires is "liquid electrical tape", which is much more useful than heatshrink in this application. There is very little clearance in the channel.

The wires are salvaged from CAT5 networking patch cables. They're 24-gauge stranded twisted pair, 4 pairs inside an outer sleeve. A quick tip for using this wire: to remove the outer jacket from the wire, use a seam ripper (think sewing, not electrical). It will slice through the jacket, without damaging the wires inside.

Main Cabin

The first photo shows a red LED, which shines down on the companionway step. There is another one mirror-image on starboard. The effect is that the step just glows red at night, with no visible means of illumination.

In the second photo, you can see one red LED just above my head. It shines down onto the forward part of the cabin. On the right (starboard) the two red blobs are sealing the back of two white LEDs. These are aimed at the stove and the sink. Once again, this involved drilling at some very careful angles.

The third photo shows reassembly. Here you can better see the location of the two forward red LEDs (the centered, large red blobs).

Wiring

Photo 2 shows the rat's nest in the v-berth, before installing the control circuit.

Switches, Control Circuit

Because of the electrical requirements of LEDs, it's not possible to just connect them to the battery with a switch. They would be really bright for a really short time!

For this reason, it's necessary to have some type of control circuit. The basic idea of the circuit is to limit the current with an LM317 regulator. My circuit is designed to provide 20 mA (milliamps) of current to the LEDs.

You can view a PDF of my circuit layout. Some details you'll still need to dig up, though, like the pinouts for the LM317LZ controllers from www.digi-key.com.

A good reference about LEDs and the required circuitry is Jobst Vandrey's site www.pocketyacht.com, which I referred to extensively while designing my system. For the keen of eye, the first photo also shows my Philips Expanium MP3/CD player.

The second photo shows the solder side of the circuit board. You can also see the starboard v-berth LED. It's mounted in a little block of teak, between the normal lamp and the CO detector.

The third photo shows the back of the switch panel. As with my main electricals, the switches were purchased at Supremetronic on Queen St. West in Toronto. The switch wires were fished through the bulkhead, and connect to the circuit board in the v-berth.

Final Result

I think the final result is well worth the effort. The first photo shows the handle-mounted LED (look at the top of the handle). You can also see the two galley LEDs, which are just to the left of the mounting screws for the teak. The grey wire is the feed for the LEDs embedded in the wood surround of the companionway.

The second photo shows the port-side v-berth LED. It shines at a 45-degree angle against the headliner.

And the third photo, which you've probably already seen. The four switches (since labeled) to control the v-berth white, cabin white, galley white, and all-round red LEDs.

LEDs In Use

Since I installed the LEDs in 2003, I've purchased a better digital camera. This one allows me to do time-lapse photos up to 16 seconds, so I finally have some photos of the LEDs in use.

Keep in mind that the light levels are not exactly true to real life, but are fairly representative of the overall effect. When your eyes are adjusted to the darkness, the LEDs provide enough light to see what you're doing.

Starting at the companionway, this is looking into the cabin at the companionway step:

Looking forward, standing in front of the galley. Photo 1 is the cabin sole, with two red LEDs pointing down. Photo 2 is the two white LEDs installed in the grab handles. Photo 3 is the v-berth white LEDs.

Closeup photos of the galley (two white LEDs, one pointing at the stove, one at the sink) and the main switch panel (two red LEDs pointing down).

The view from the cockpit, first with just the red LEDs illuminated, then with the white cabin LEDs as well.

While we're in the cockpit, the compass and knotmeter illuminated. The compass has a cover that swings down to illuminate the front edge of the dual-read card.

And two photos from the dock, showing the reflective tape installed on the mast, MOB pole and life ring. The masthead tricolor and steaming light are both turned on as well, although this particular lighting combination should not be possible, as it's not legal. The steaming light must only be used with the on-deck navigation lights. I wasn't aware of that fact when I wired the boat.