Index

LED Lights on Your Boat - Minimal Power Consumption.
INDEX - Cabin, Cockpit, Running, Steaming, Stern, Anchor, Instrument, Windex, Transient Suppression, Important Note.

There is hardly ever enough electrical power on a pocket cruising sail boat.  This is why I installed two solar panels to charge the battery, one on each side, so at least one is exposed to the sun.  Even this doesn't work all the time but it is a huge improvement over a single panel.  That was during 2002 when a shade tolerant panel wasn't available.  While increasing the generating capacity is one technique, another is to reduce the power consumption by replacing all the incandescent bulbs with LEDs, especially high intensity white LEDs.  If you always motor at night with a generator running or sail for only a short time you might leave the running lights as incandescent.  But if you sail at night for a lengthy time without a generator running you should definitely convert the lights to LED to reduce the drain on the battery.  In either case, the lower power consumption of LEDs means the generator can charge the batteries quicker. 

CABIN LIGHTS - The factory faux wood light fixtures installed at the top of the SJ23 compression post are a bit wanting for illuminating the cabin with the incandescent bulb.  The fixture is temperature rated for an 1141 incandescent bulb (automotive 12V clearance bulb or park light) that has a single contact base (bayonet pins in line).  It can be replaced with an equivalent LED bulb (1141 or 1156) to reduce power consumption from 1500MA to 200MA and improve the quality of the light.  The surface mount LED bulb shown at left is perfect for this light fixture since all the side light bounces off the reflector and a small amount is cast forward, leaving no shadows.  This bulb comes in warm white (incandescent) or cool white (day light) colour.  Apply a light coat of dielectric grease to the bulb base to prevent corrosion in the socket.  Its doubtful you will touch this bulb again in your lifetime.  That's why corrosion protection is so important.

Since the daylight version of an 1156 LED is brighter than an 1141, you may find it desirable to reduce the light intensity with a power dropping resistor (80Ω, 1/2W) operated by a switch installed on the base of the fixture.  This further reduces the current from 200MA to 50MA.  With the high setting I can read at the table into the wee hours of the night and not worry about being able to use the electric start outboard in the morning.  In addition, aging eyes require twice the light that youthful eyes do.  However, on the low setting I can operate the light in the middle of the night and not be blinded by it. 
NOTE - DO NOT install a resistor for an incandescent bulb.  That resistor would get really hot and melt the fixture. 

Even with the brighter LED bulb in the pedestal fixture I considered the edge of the cabin to be too dark.  For this reason I installed warm white LED strip lighting along the cabin sides.  Another strip was installed at the aft end of the cabin with an additional spot lights over the power panel and galley.  The beauty of strip lighting is that it takes so little space and casts its light out at 120 degrees.  While a strip of 12 LEDs draws only 120MA at 12.5V, each is equipped with a switch to control power consumption.  You should install indirect lighting since the light from an LED can be intense.  That's why installing them behind the down turned lip of the head liner is such a natural thing to do.  Shadows are always a problem in a small cabin.  LED strip lighting can be cut to length at the marked 12V cut spots to suit an installation.  The strip is adhesive backed which makes installation easy.  Imagine what you can illuminate with a flat strip of LEDs like this; forward berth, main cabin, cockpit lockers, etc.  Since they're flat they don't get in the way.  Apply the adhesive strip of LEDs to the bottom of a varnished stick, add a switch to the end of the stick, fasten the stick with a screw behind the down turned lip, then run the power cord to the breaker panel.  It looks so much classier if you install these LEDs without showing the wire.   For the starboard light I left a coil of wire tucked behind the lip for future servicing then ran the wires forward to the bulkhead where it goes down along the hull.  This is where I drilled a small hole through the top of the settee and bundled the wire with others going aft to the power panel. 

Shown below is the power panel illuminated at night and a view into Panache's cabin as I approached from a dock.  The anchor light is glowing over the cockpit.  This is the first time I've seen the cabin illuminated from the outside and the cockpit bathed in light.  A nice warm, welcoming feeling. 

Other useful locations for LED lighting would be inside a locker to find stuff at night, under the table to light the cabin sole, under the companionway to light the steps and in the forward berth for reading.  Maybe later.  In the mean time enjoy the light.   TOP
 

CABIN NIGHT LIGHT - When I installed a pedestal support post (Tech Tip C01) on Panache it required a bracket across the ceiling to anchor the post to.  That part was easy.  I just glued a (2x6)" of light weight cedar to the ceiling using silicon sealant.  Installing LEDs in it was a natural.  I decided on two clusters of high intensity LEDs, one white and the other red as shown here.  Each cluster consists of three LEDs wired for equal brilliance and minimum power consumption.  Assuming 14.0 VDC applied to 3 LEDs wired in series, I used a 200Ω resistor for the white LEDs and a 400Ω resistor for the red LEDs.  Both are 1/4W.  Each LED requires 2.2-3V to operate.  Today I wish I had installed LEDS on the angled sides as well but they were very expensive at the time and I had kids to feed.  When installing the electrical wiring in the ceiling anchor, it is best to connect the wires on a terminal strip.  I installed a terminal strip in the middle of the cedar, behind some smoked acrylic.  This makes it fairly easy to connect the LED wires to the electrical harness and to service them.  This is where I installed a diode across each bank of LEDs.  See protect below.

The purpose of these lights is to illuminate the cabin without affecting my night vision.  I was doing a lot of night sailing in 2005 and wanted low power lighting.  To that end these lights are a success and it is oh so sweet to have them.  However, you might want to operate the LEDS at full brightness and install a dimmer switch to fine tune the brightness to your night vision.  Everyone's night vision needs are different.  The LEDs are NOT adequate for reading which is why I added the low intensity switch to the pedestal lights and the indirect lighting to the ceiling.  But I'm also considering a light under the table for those times when I need it brighter after waking up in the middle of the night.  It creates a more indirect lighting effect in the cabin.

PS:  LED lighting was in its infancy in 2005 at the time of this installation.  I bought a handful of the original dual in line pin high intensity white LEDs from a local electronics wholesaler.  This was only a few years before white LEDs were available.  Today's LEDs are far more energy efficient.  I tested red and white LEDs in their dark room and was surprised at how well they illuminate and how well I could see with this quality of light.  There is no shadow to the edge of the light.  The brightness simply fades smoothly to darkness at the edge of the beam so the human eye doesn't have to deal with the sharp contrast there; a phenomena that is typical with a reflector behind a filament bulb.  Since I wanted good night vision, to which I might occasionally add soft white light, I chose the medium intensity LEDs.  See Note 1 at bottom.
That was then.  After a few years of use I now suggest using high intensity white LEDs to get the most light for the power consumed.  I've also discovered that I can retain my night vision by switching the white LEDs on with the red LEDs.  I do this occasionally to find my "vitamin J" in the cabin; great cockpit food during a night race or a cruise when it is simply too difficult to prepare food in the dark cabin. TOP
 

PORTABLE COCKPIT LIGHT - Your basic solar garden light, available from any home improvement store or garden nursery, can make an effective cockpit light.  Mosquitoes seem less attracted to it than an incandescent light.  Hurray!  It's nice to have a bit of light in the cockpit for an extended social hour and it's a real pleasure to step into an illuminated cockpit when returning from a shore event.  The light can also be moved to the cabin for a night light; good enough that you don't stumble into things when you have to pee in the middle of the night!  It sure beats a candle or smelly hurricane lamp.  The beauty of a garden light is that it is a self contained water tight unit equipped with a solar panel, battery, 360⁰ lens and is dirt cheap.  By the way, there actually isn't a light sensor in one of these.  The absence of charging voltage automatically sends battery power to the LED. 

NOTE to ALL: A solar garden light sucks as an anchor light since it is barely visible at 100' (33M), doesn't shine longer than 6 hours and for these reasons does NOT meet Collision Regulations.  Stay up one night and you'll see for yourself.  This means it can't shine through a night unless you live North of 60⁰ where a summer night is barely perceptible, having only a few hours of dusk.  Use an approved anchor light in the presence of other boats, especially commercial traffic.  Although in a pinch a garden light is better than leaving an anchored boat dark.   TOP
 

RUNNING (NAVIGATION) LIGHTS - The factory bow running light fixtures require a 1416 bulb that draws 700MA, (bayonet base, single terminal, incandescent filament).  The tiny fixture was probably OK in the 1970s when there were fewer boats and little commercial traffic but I question if they have a 2 NM range, mounted so low on the bow cap.  Panache's certainly didn't.  Replacing them with a light fixture similar to the one shown below (Aqua Signal 25) or in Tech Tip B26, is a huge improvement in visibility.  The filament of the festoon bulb is positioned in the focal point of the Fresnel lens to meet the requirements: 120⁰ horizontal arc visibility and 2 NM of range visibility.  Note that the vertical arc of visibility for a sailboat is +/- 25⁰ to accommodate heeling, which is larger than for a power boat +/- 17.5⁰.  This is a specification is seldom reported on the packaging.  However, the incandescent bulb this fixture comes with draws 900MA of current.  There is a huge power saving to be had without sacrificing light performance when the bulb is replaced with a matching LED.  Low power drain is especially important on a pocket cruiser that has little capacity to charge the battery. 

For years I was reluctant to exchange my incandescent bulbs to LEDs since it was expensive to convert them and difficult to justify for the few times I motor or sail at night.  Late in the evening (23:00 at the height of summer) I usually motor to my mooring or an anchorage so the 2.7A draw of all my incandescent bulbs can be handled by the 6A generator in the outboard.  But if the battery is also low the generator can barely charge it with the extra load.  When I do sail this late in the evening I usually have a >4KM visibility and I'm generally the only boat on the water, so no problem.  However, If you live in the southern US where it gets dark much earlier and you have to deal with commercial traffic, I would seriously consider LED bulbs.  Three LED bulbs draw less power (approx 330MA) than three incandescent bulbs (2700MA). 

Using a flat cluster of warm white SMDs is optimum since it is the same colour temperature (3500 Kelvin) as an incandescent bulb.  Only the red or green frequencies pass through the corresponding lens and the rest are blocked, which also applies to an incandescent bulb.  While the blocked light is waste, the LED cluster uses only (100MA) current compared to the incandescent bulb (900MA).  Therefore an LED is a huge improvement over an incandescent bulb as the current and heat are greatly reduced while improving light intensity.

1. The main attraction to LED lightning is low power consumption with high light intensity.
   (At 100MA the LED is much brighter than the incandescent bulb, being too bright to look at with the unprotected eye). 
2. The optimum angle of radiation for maximum effectiveness behind a Fresnel lens. 
   (The SMD construction radiates light in one direction with a 120⁰ beam angle making it ideal behind the Fresnel lens of a running light).
3. The correct light frequency radiated (colour temperature in degrees Kelvin). 
   (The colour temperature in very close to the incandescent bulb making it a match to the red & green lenses of the fixture).

So for Panache's running lights (Tech Tip B26) I chose to install a 578 festoon white directional bulb equipped with 8 surface mount diodes (SMD) purchased from SuperBrightLEDs.  My friend chose to install a USCG certified white omni directional bulb (part # unknown) on his boat.  The brighter LEDs on the certified bulb are installed around a round core.  Since we have the same fixtures it was a perfect opportunity to compare a directional versus an omni directional bulb.  The results are as follows: 

Measuring Light Intensity - A lumen meter measures light power using all colours of the visible spectrum.  It is an accurate way to measure white light but can be deceptive when measuring a single wavelength (frequency) LED.  Because multiple wavelengths create white light and a coloured LED has a single wavelength, the LED will show a lower lumen reading.  However, the coloured LED will appear to the eye to be equally as bright as a white bulb. 
Since my 1970s light meter no longer works, my next best meter is an App in my cell phone.  It reads light intensity indirectly by giving the photographer the three essential settings for a camera.  The aperture and ISO speed are set manually and it then measures the shutter speed.  This App can hold the displayed readings and store the results in a photo for field work and future comparison. 

STEAMING/DECK LIGHT - SJ23s built much later than Panache were equipped with a steaming light.  Not so Panache.  For years I never bothered to install one since it is so bright late in the evenings in Alberta and I'm the only guy crazy enough to be out at that time.  It is also difficult to install the wiring half way up the mast.  To date I have worn a forehead light to illuminate the deck and have no problems with it; light where you look, without a shadow, leaving your hands free to do whatever.  My dentist also told me to quit holding a flashlight in my mouth!  I once worked on a fore deck illuminated by a ridiculously intense halogen deck light.  The visibility was excellent until it was switched off and instantly I couldn't see, having lost my night vision.  Didn't like that very much!  An LED light would have been so much better.  However, not showing a steaming light in the presence of commercial traffic is asking for trouble so you may as well install one.  Twice a year we have fireworks at either end of the lake.  Once the show is over all ~200 boats leave at the same time.  Motoring along with several hundred boats not showing the correct lights is asking for trouble.  So in Spring of 2018 I installed a Victory AAA steaming/deck light 6" above the spreaders for the required 2NM white light shining in the forward 225⁰.  I drilled a 1/4" cable entry hole through the front of the mast and shaped it to an oval by tilting the drill bit and smoothed the edges with a file.  Then I fished the wiring through the mast with a 1/8" fibreglass rod (fish tape), keeping it separate from the internal halyards.  It was be supported to the inside of the mast to prevent slapping and fatigue.  This is definitely a job to be done with the mast down.

VICTORY AAA FIXTURE
Steaming Bulb - A 578 LED bulb shown here (warm white 3000K, 60 lumens), 225⁰ beam.
Deck Bulb - Dual pin bulb in bottom of fixture.  This bulb is bright enough for foredeck work without affecting night vision.

ROAD GRIT - The bottom (deck light portion) of a Victory AAA steaming/deck light is open and points forward when traveling down the road with the mast horizontal.  As such it can scoop road grit and rain water.  To avoid this, smear grease in the socket to prevent corrosion and tape the bottom of the fixture closed.  Fortunately the bulb cluster is sealed at the bottom (shown at right) and won't have this problem but I will still tape it to protect the surface of the bulb if I'm traveling a long distance. 

VISIBILITY - One should not forget how effective a mast light can be to illuminate the deck for night work or to make yourself temporarily visible to other vessels.  Its not regulation of course but if it looks like the other vessel is maintaining a collision course to you I'd switch on the deck light.   TOP 

STERN LIGHT - Panache's dim factory stern light did little to warn a boater from running her down at night.  Fellow sailors have commented they didn't see Panache's stern light till they were very close.  It doesn't help that my boarding ladder blocks some of the light, so I can't blame everything on its size.  However, I have never been happy with this dim light so an Aqua Signal 25 stern light replaced it in 2018 to ensure the required 2NM visibility with a 120⁰ wide beam. 
- The Aqua Signal 25 stern light is mounted on the top UHMW clamp of my anchor light.  This height creates minimal reflection from the water and doesn't block access to servicing the outboard.  Fitting the light to the angled pushpit post required a compound cut to ensure the Fresnel light casts its beam horizontally over the water.  Given the fact that "nothing" on a sailboat hull is straight, this cut was a tad difficult to mark while the boat was on the trailer on rough ground.  It would have been much easier with the hull floating!  The external wiring was encapsulated inside the tube with the connectors hanging out the bottom.  The factory wiring under the cockpit was redirected from the port side to the starboard transom fitting.  The easiest way to accomplish that is to push a fish tape in, tape the wire to the end and pull it out.  The factory wire on Panache was long enough.  Once outside, the wire was terminated with a 2 prong connector, similar to the anchor light.  The grip of the UHMW clamps on the SS tubes is tight enough to prevent rotation.  Shown below is a trial fit of the light during a fitting in Fall. 

NOTE - To store this light assembly for trailering, I loosen the nuts on the cockpit side of the clamps, remove the assembly, then screws the parts together so I don't loose anything and store the assembly in the cabin for winter.  It rides nicely on top of my galley cabinet. 

The factory stern light was removed from the transom and the hole capped with a colour matching disk of fibreglass as it is too difficult to do an epoxy and colour matching gel coat repair in this tight space.  Besides, this way I can always reinstall the light if I have to.  I can finally place my foot here!

ANCHOR LIGHT - An incandescent anchor light can draw a lot of power from a battery since it operates for a LONG time without a means to charge the battery.  This is typical in southern US latitudes or during a shoulder season in northern US or Canadian latitudes.  To reduce power consumption use an LED light and operate it automatically with a darkness switch, unless you enjoy getting out of bed to shut it off with the rising sun!  I struggled with where to install it; at the mast head (regulation height as of 1850) or lower to the water (in line of sight to power boaters).  Ultimately I chose a low light that is directly in the line of sight to the local "cowboy boaters" who motor around during their romantic evening outings, with anything but navigation on their mind.  These people never think about floating hazards and are oblivious to collision regulations.  To them the lake is an empty "parking lot" to tool around on.  My other reason for not installing the light on the mast head is that it often blends in with the stars or shore background lights, making it more difficult to see.  Plus, the local power boaters NEVER look up.  For these reasons I installed a bright 360⁰ anchor light installed 10' above the surface.  It is so effective that the cowboy boaters now give Panache a wide berth when on her mooring and other sail boats use the light as a beacon to enter the bay.  A lot can be said for operating another light at the bow to show hull length or a cockpit light to increase the visibility.  Cabin lights don't show very well through the windows.

I fabricated this anchor light in 2016 using 8 high intensity dual in line pin (DIP) LEDs pointed horizontally and equipped it with a darkness switch that consists of a light dependant resistor (LDR) mounted on top, pointed up.  The anchor light looks similar to a Bébi light that was once manufactured in Fiji but the electronics is my design. 
"Too bad Bébi was forced out of business.  I was eyeing their design for a long time and buying one would have been a whole lot simpler than making one!  It isn't till you fabricate one of these that you really appreciate their design.  Oh well I had bags of LEDs and nothing but time on my hands during the winter." 
My bench testing verified it unnecessary to regulate the power to the circuit.  While the light intensity is slightly less at 11V, (virtually a dead battery), the reduced intensity is barely perceptible 1/2 KM away.  Besides, a regulator would complicate the design and draw more power.  If you want to be picky about equal illumination of all LEDs, test each at 11V and measure the light output with a photometer, then use similar performing LEDs together.  There was no pretext to design a "2 NM" (3 KM) light with my design.  At the time of fabrication Panache was moored in a 1/2 KM wide bay where that range is not required and the brightness of a 2 NM light would be annoying to the cottage owners.  But if the number of LEDs are doubled this design can easily be a 2 NM light, albeit with double the power.  Having said this, the light is visible 2 KMs away on a clear calm night.  There is a slight reduction in light if you are 2 NM away, between 2 beams.  This is due to the DIP LEDs that radiate in a ~20⁰ beam.  Up close this is barely visible.  The beams are cast across the water in a horizontal pattern similar to a lighthouse with a Fresnel lens.  For this reason, ensure that the mounting staff is perfectly vertical to cast a flat circle of light across the water.
In 2021 I discovered the anchor light drew low power continuously and it no longer switched on at night as the LDR had lost its acrylic cap due to UV damage.  So I scrounged a new LDR and window from a surplus wall mounted night light.  The plastic window was epoxied into the top of the cap to protect the LDR from UV and I replaced the dead LDR.  This was way easier than buying the separate components.  I also added a threaded brass rod through the center of the light to clamp the cap down to the base.

    CASE ASSEMBLY - The PVC potable water components are available at a home improvement or plumbing shop.  For a stiff mast I selected the 1/2" ID, thick wall tubing and removed the outside printing with fine sandpaper so it looks presentable mounted on the boat.  For the LED housing at the top I used a 2" OD end cap with a matching size base.  All 3 fit together quite nicely.  Cut off all but 1/4" of the threaded portion of the base so the remaining thread functions as a lip to support the circuit board.  Drill a hole through the base to fit the mast to.  Make sure it fits snug over the tube and is held with epoxy.  Bevel the top inside circumference of the mast (tube) to a smooth ridge for the power wires that will go down.  Drill some 1/8" ventilation holes through the base.  The cap is clamped to the base with a threaded brass rod down the center.  Because it goes through the circuit board, the top of the rod is insulated with heat shrink.  Since the light is permanently mounted on the transom the 1/8" rod extends through the top as a bird spike.  Last thing I need is poop covering the light sensor.  Click here for case assembly.

    CIRCUIT DESCRIPTION - This "switch" consists of a transistor (Q1) controlled by a voltage divider consisting of a light sensitive switch, a current limiting resistor (R1) and a potentiometer.  The light dependant resistor (LDR) switches the circuit ON in darkness and OFF in light.  An LDR goes to low resistance when illuminated and high resistance in darkness.  Once the transistor conducts, the LEDs light up.  Diode (D1) is wired backwards across the input power leads, to protect the LEDs from a voltage pulse or aerial electrical surge that might burn them out. 
- To test the transistor (MPSA06 or 2N3904), touch the base lead with a ground and it should switch the 8 LEDS off.
- To adjust the light sensitivity, cover the LDR to forward bias the transistor and adjust the potentiometer for a total current of about 30 MA (max intensity).  Alternatively, adjust the pot to the darkness switching point you desire.  Its a good idea to apply a small piece of electrical tape to the top of the potentiometer to protect the internal carbon track from moisture. 
- Once the electronics works, spray the board and inside of the cap with a conformal coating to protect against corrosion. 

    CIRCUIT BOARD ASSEMBLY - Solder all components to the Veroboard and wire the LEDs using ~3" long #24 stranded wire.  The insulation must cover the wires completely for final assembly.  Solder the input power cable to the bottom of the Veroboard since it is the natural direction of the wires going down the hollow PVC staff.  The power cord exits out the bottom to a plug.  Click here to see my schematic, Veroboard component layout (X denotes where to "open" the PCB run with a drill bit) the run side, & the component side of the 1.5" OD circular board. 
(COMPONENT SIDE - The red & black wires below the potentiometer shown on the component layout are my temporary external power leads.  Do not include them in the final assembly.  Instead, solder the permanent power wires to the bottom of the board.  The grey cable shown below is a 4 conductor power cable.  I've doubled up the wires to use all conductors for minimal power loss). 

    FINAL ASSEMBLY - Form the LED wires together into a bundle and then fan each LED outward like a flower as shown on right.  I used needle nose pliers to point the LEDs outward.  Line up each LED with a hole drilled through the side of the cap.  Smear silicon sealant in each hole and push the LED in to collar depth.  Remove excess sealant from the exposed outside of each LED.  Once the sealant has cured (24hrs) form the bundle of wires into a spiral coil so it can be pushed (screw fashion) inside the cap as it goes down over the rod and onto the base.  Do this with the power on so you can detect a problem during assembly.  This is the test to confirm everything is well secured and insulated.  Once the cap is down on the base and all 8 LEDs are still lit, you are good to seal the unit.  Spread a thin bead of silicon sealant around the base and snug up the nut on top of the rod.  The only way to service the electronics is to release the nut and cut the sealant with a razor knife.  Relax, it should last a lifetime. 

    INSTALLATION ON BOAT - Panache's anchor light is mounted on top of a 44" mast (PVC tube) positioned where there is a 360⁰ clear visibility above cabin height and below the boom.  The staff is supported inside a SS tube clamped to the aft side of a pushpit post where it is out of the way.  The UHMW clamps shown below are amazingly strong.  The PVC staff is heat bent so the upper portion is vertical for flat illumination across the water.  A small screw through the bottom of both tubes locks the staff in place; up/down and axially.  It is quite easy to remove the entire assembly for road travel but I have occasionally left it on with no problem.  You should be able to adapt this technique to your boat. 

    ELECTRICAL CONNECTION - The power cables exist out the bottom of the mast and plug into their mating connector installed through the transom.  Achieving a water tight cable through the solid fibreglass transom is fairly easy if installed as shown.  Drill a hole through the transom, slightly larger than the cable, with the drill bit pointed slightly up towards the gap below the starboard coaming.  Push a fish tape into the hole and through the gap.  Then pull the power cable out through the transom hole, leaving the connector hanging out.  Seal and screw the cable cap over the transom hole.  Slip two ferrite beads over the power cable at the battery to ensure "clean power" to the LEDs.  Later I may add a power switch to shut it off for night sailing or when I "borrow" a slip at a local club.  No point in annoying the animals in the zoo or I could find myself floating in the bay come morning!  For now I will just pull the connectors apart.  While I thought other sailors would object to my anchor light, most welcome it saying, "I can see the dock while walking to my boat at night."

To test the light I installed it on Panache while she was on her trailer parked in the bush.  I can report that it is easy to see from 300' away, which is good considering there was no snow at the time to reflect light.  I built a second light for my buddy and he reported that in total darkness the light cast his shadow against the house 30' away.  This is good performance for only 22 MA of current on his light. 

The anchor light is even more visible over water.  The night photo at left was taken about half way through dusk with a digital camera.  Shortly afterwards I drove to the far shore shown in the photo and I could see my light with the naked eye.  That shore is about 1 KM away.  This is good performance for only 30 MA of current.  The light from a DIP style LED radiates in a 20⁰ beam, so it is very bright when you are in line with the beam. 

At right is a photo I took without a flash to show just how well the cockpit is illuminated at night.  I think I could actually read by this light. 

NOTE - The two night photos shown here are a bit deceiving because a digital camera can penetrate darkness and rain better than an analogue camera.  I don't know why but it can create some cool effects.    TOP

INSTRUMENT LIGHT - Is can be quite an improvement to replace a tiny incandescent instrument bulb with an LED.  I've modified all my instruments to LED lighting to improve the visibility, reduce the glare with the softer light and reduce power consumption.  In most cases this change is not difficult to do but if you can buy a plug in replacement it is usually the best.   TOP
 

DAVIS WINDEX 15 LIGHT - Panache's Windex light is connected to the same circuit as the cockpit instruments.  Its a tad important to see all of them when moving in the dark!
- Notice that the wiring goes vertically through the top of the mast head.  This eliminates fatigue stress.  The holes are sealed with butyl rubber to prevent insulation chafe and stop water flow down the inside of the mast.  Wiring through mast head. 
When I acquired Panache she had very low battery charging capacity which is why I replaced the incandescent light with an LED, as shown at right.  It resided at the middle of the mast head.

1 - This was my first version LED light to replace the Davis light that was "punched out" by hail.  What are the odds of two small objects hitting each other, with both of them moving? 
2 - After a number of years the LED burned out due to an electrical surge (EMP) from lightning.  So I replaced the LED and connected a diode (1N4007) across it for surge protection.  This operated for years so I assumed the diode was doing its job, imbedded in the wiring.
3 - One evening I went for a float only to discover the tabs & pointer barely showed.  Hmmm.  When I replaced the LED I mistakenly installed one that radiates a beam of only 15⁰.  So not wanting to lower the mast, I waited till winter to replace it with an LED having a 90⁰ beam and increased the current from 15MA to 20MA.  The Windex showed slightly better next summer but it still wasn't good enough to see at a glance!
4 - My final version is a return to the Davis weather proof light fixture #3200 that now comes equipped with a rugged surface mount LED.  It draws only 23MA and radiates at 120⁰.  The new light is installed aft of the Windex where it can illuminate the tabs and have some hail protection by being close to the shaft.  I also painted the bottom of each tab and pointer ends with luminescent day glow orange paint to reflect the light.  The tabs and pointer show up like daylight against the dark sky.  Combined, these upgrades equate to optimal visibility with minimal current drain. 

To protect the LED from an electrical surge I added a diode (1N4007) across the power leads, imbedding it in the fixture wiring.  (Delicate work of this nature should NOT be done at the mast head.  It is best to add this diode & connector to the wiring harness on a workbench, then install the assembly at the mast head).  

NOTE - The LED/diode combination does not radiate RF to the adjacent VHF antenna.
REPLACEMENT PARTS - Bulb #R3201L,  Lens #R3200B.  TOP

PROTECT an LED FROM a TRANSIENT VOLTAGE - A word of warning about sensitive electronics like LEDs connected to the boat wire harness.  An LED is susceptible to burn out from a voltage spike that exceeds its rating.  For example, when an inductive load like a fan motor or bilge pump equipped with brushes or a relay coil is switched off, the collapsing magnetic field in the coil will induce a voltage spike in the opposite polarity on the wire harness.  The spike is usually large enough to burn out an LED that is switched on, regardless of which circuit it is wired to.  But its almost a sure bet to burn out if it is wired to the same circuit.

Similarly an LED that is exposed to the atmosphere (Windex light) can burn out due to an aerial charge (EMP) associated with lightning.

I relearned the lesson of transient voltage protection the expensive way during my installation of the cabin ceiling LEDs and cooling fan.  They happen to be wired to the same circuit.  In 2004 there were lots of relatively inexpensive electronic "toys" with LEDs available that would suggest that LEDs were cheap.  This was correct for the coloured LEDs, but certainly not for the high intensity white LEDS that cost $5.00 Ca each.  I bought mine at a local electronics wholesale where six red and six white (low intensity) LEDS cost $20.00 Ca.  By 2009 the costs were down considerably. 

The simple solution for both problems is to connect a transient voltage suppressing diode (P6KE) or a low power diode (1N4007) across the fan motor or relay coil to short out the voltage spike right at the source.  A transient diode can switch on much quicker than a low power diode, making it the superior device.  Its best to connect the diode as electrically close as possible to the source to prevent the spike from propagating across the circuit.  Connect the cathode (striped end of the diode) to + and the anode to - (negative).  The normal power flow to the LED is not affected.  The diode conducts only for the reverse polarity voltage pulse impressed on the LED, effectively shorting it out to protect the LED and anything else connected.  Diodes are inexpensive and provide effective protection.   TOP

________ NOTES _________

NOTE 1:  Because an LED emits light in a very narrow frequency band, you may perceive the LED as slightly dimmer than a broader spectrum tungsten filament bulb.  The light receptors in your eyes react slightly different to narrow spectrum LED light than to broad spectrum filament light.  Instrument lights can be blue or green yet not interfere with night vision as long as the intensity is kept low.  This makes it easier to read fine text or the tiny graduation on a meter scale and is what retains your night vision, making an LED so beneficial.  A dimmer can be made from a potentiometer or a variable regulator. 

Here are some facts about human eyes and light;

• Compared to white light, red light tends to make things slightly fuzzy due to the longer wave length of red light. 
• Blue light produces the sharpest details due to the shorter wave length. 
• Blue light is needed for depth perception. 
• For a given light power input, the human eye perceives blue light as being somewhat less intense than red, with retained sharpness. 
• As humans reach their fifties, many require double the amount of light to see small things than when they were in their 20s. 
• Men have slightly better night vision than women and can read smaller text. 
• Don't limit yourself to a marine fixture.  There are many suitable automotive, bicycle or camping lights available.

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