$3 for a 6W LED interior light

[susswein]

2 X 3 6W 5050 SMD Dome Light US$4.99 only

I'm not affiliated with the site, just passing on what seems like an excellent deal. At $3 each you could carry a few spares in case they don't stand up long-term to the marine environment.

[belizesailor]

In my experience, there are usually "cheap" LEDS and "good" LEDs, but they are not usually one in the same (similar to batteries). This one does not give voltage range specs (only broad reference to 12V). Most fixed voltage LED's fixtures I've bought just don't hold up for long. Better quality units, with circuitry to protect the LEDs and support a wider range of operating voltages tend to be better quality and hold up better.

I suggest you ask the vendor for more detailed specs -- especially voltage range.

But, sometimes hard to tell from an Internet add, if you buy some and try them out then let us know.

[irwin37]

They will most likely need a regulator. When they say 12 volts they mean 12 volts,, not 13.5

[Ram]

I just bought 6 to give a try- $18 usd cant go wrong at this price

[raphaella]

I've bought 100 form china at 1.38 each, delivered at home in Canada, have them installed all over our cat, some 6 watts, 9, and 12 and they have been running for the past 2 years. The qte 100 was to have some for sale in Grenada and believe me, NO MORE, sold them at 4$ and everybody is happy with the result. Go on E-bay that's where I went and they have different shades of white, from soft to pure white brightness.

[brankin]

Originally Posted by raphaella

I've bought 100 form china at 1.38 each, delivered at home in Canada, have them installed all over our cat, some 6 watts, 9, and 12 and they have been running for the past 2 years. The qte 100 was to have some for sale in Grenada and believe me, NO MORE, sold them at 4$ and everybody is happy with the result. Go on E-bay that's where I went and they have different shades of white, from soft to pure white brightness.

Could you share the link to the site that sells these?
Thanks

[Nicholson58]

There are many threads on this site about this. It always starts with some one finding an incredibly cheap LED light. The item is always an automotive part. These are designed to operate at 13.5 VDC since, in use, the vehicle engine is on 99% of the time. The worst of these may have a 3.5 volt LED with a 10 volt drop over a resistor in series to account for the total required voltage drop. This wastes most of the power fed to it. The best may have several LEDs in a festoon to arrive at the 13.5 volts. These are OK from the power point of view but, when they are operated at reduced voltage, a normal occurance on a sailboat, the output falls and may, in fact drop below the drop-out voltage. At this point - no lights. At charge conditions, it may be operating at too high a voltage (shortend life). For a festoon to work well, the LEDs have to be matched.

The Expensive LEDs have a current regulating circuit. There are several popularly used. The recognized best is PWM (pulse width modulated). In this circuit, the LED is switched on and off at around 20 to 30 KHZ. The ratio of off to on time is controlled to yeild the designated forward current required to reach the rating of the LED. If the system voltage is high (charging) or low, the LED will continue to put out its rated lumens. It has the lowest parasitic power loss. We operate a 24 VDC vessel which means my DC can be 29 volts. My LEDs operate from 9 to 90 VDC with no change in performance. With all 60 cabin lights on my power reads 0.4 amps at 26 VDC.

PWM controller integral to the back of the bulb.

The point is: Just because you switched to LEDs doesn't mean you are vastly reducing your power use. In sales and marketing terms, you have left money on the table.

I have also studied the LED 120 VAC replacements at Home Depot. The control method here vastly effects the ratio of lumens/power. As in boat LEDs, the cheap ones don't save that much and the get hot as heck. Some are not much better than a CF. Keep this in mind if you also replace 120 volt bulbs on your boat. I assumed that they might be used if the inverter was live. At the very least, they reduce the heat output.

The two links below are to some of the best guides to the technology.
Marinebeam Replacement LED bulbs for your existing boat fixtures PWM regulated

Bebi Electronics-Installing Marine LED Reading, Navigation and Running Lights! not PWM but pretty good

These guys offer PWM on their replacements but no tech discussion. Marine Lighting Bulbs - Boat Lights - Yacht Lights - Imtra

You get what you pay for IF you educate yourself.

[S/V Alchemy]

^ ^ ^

Agrees with my research and experience.

There is a place for cheapo LEDs: wired to 9V batteries and linked to contact switches inside lockers or under locker lids. Open and a weak, blueish light goes on, just enough to show you what's inside. Close, and the light goes off. Use enough contact spray and they should last two years. And, no wire runs.

But for lights used for reading, general area illumination, or navigation, go "regulated" and "warm white". Try before you buy. See if the light varies at 12.1 V on the house bank versus shore power/on charge. (hint: it shouldn't). See if you can get dimmable LEDs. Experiment with strips behind cabinet trim: indirect lighting is very pleasant on a boat at night.

LEDs are almost as opinion-making as anchors...almost.

[s/v 'Faith']

Thanks for the link.

Just ordered a bunch, looking at them I am pretty sure they are the same 3w units I bought from another mfg. a couple years ago for a lot more $.

Wish I had looked around their site longer before I ordered, the have some great deals on flashlights (3 w Cree AAA for $4).

[mrm]

If something looks too good to be true... it usually is.

Compare the product linked by OP, which uses 6 LEDs in '5050' size and claims astounding 6W (or does it?, maybe '6W' is just a product name?) to this product:

5050 SMD LED CREE 4W GU10 Bulb 120V Cool White Dimmable - USA SHIP L.E.D | eBay

which uses 24 LEDs in '5050' size (from a reputable manufacturer) and lists a 4W output (and has much better heatsinking).

Draw your own conclusions.

[susswein]

I suppose that all the issues/problems discussed here are theoretically possible, but I haven't experienced any of them. I bought the cheapest 12V LED bulbs I could find off of ebay, and have about a dozen total installed in both my solar-equipped camper van and my boat. In 3 years I haven't had a single failure, and compared to the 12V fluorescent fixtures they replaced use about 80% less energy.

It makes sense to pay the $$$ for high reliability for something that's safety related of a pain to replace (like a mast top anchor light), but a cabin light is not critical, it's redundant, and trivial to replace. For someone on a tight budget (like me) it seems like the perfect place to save some money.

[mrm]

Originally Posted by susswein

I suppose that all the issues/problems discussed here are theoretically possible, but I haven't experienced any of them. I bought the cheapest 12V LED bulbs I could find off of ebay, and have about a dozen total installed in both my solar-equipped camper van and my boat. In 3 years I haven't had a single failure, and compared to the 12V fluorescent fixtures they replaced use about 80% less energy.

Sure, everybody has different requirements and comfort levels. But, from a purely engineering point of view it was impossible then to replace fluorescent fixtures with LEDs and use 1/5th of previously used power. I understand replacing as changing the light source while keeping the amount of light the same.
It all boils down to luminous efficacy of the light source and to the beam directionality. CFLs have luminous efficacy of approx. 80 lumen/W.
Commonly available white LED sources from 3 years ago had efficacy of approx. 40-70 lumen/W. So to get equal luminous flux (lumens) you would actually need more power when using LEDs.
However, LED sources are directional, their luminous flux is contained in a cone, so less lumens are needed to make a surface (eg. a table) appear to be as brightly lit as it was with CFLs (iow to have the same illuminance, measured in lux (1lux = 1lm/m2)). But then only a surface is lit and the surroundings are darker.

It makes sense to pay the $$$ for high reliability for something that's safety related of a pain to replace (like a mast top anchor light), but a cabin light is not critical, it's redundant, and trivial to replace. For someone on a tight budget (like me) it seems like the perfect place to save some money.

Again, it depends. If it is general lighting, almost anything goes. If it is reading light, you would probably feel eye discomfort much sooner with low quality light and any 'savings' will be quickly spent on glasses and doctors. Same goes for cooking area lighting, good quality light makes products appear tasty, while bad quality light may take your appetite away

[susswein]

The lights I replaced weren't CFLs, they were thinline fluorescent tube fixtures. Each fixture had 2 9W tubes, so 1.5A draw. The LEDs I replaced them with were Ikea 12V puck lights with the halogen bulb replaced with a GU5.3 (?) soft white LED "bulb" consisting of about 12 surfacemount LEDs. I paid between $5 and $10 each for these "bulbs" on ebay, and each bulb drew a measured .15A. I don't have any way to measure actual lumens of output, but 2 of these puck light "felt" like the same amount of light as the thinlight, and only drew .3A total. I generally read for a few hours each night and haven't noticed any eye strain with the LEDs, and they certainly don't seem to have affected my appetite (although that might actually be a good thing :-)

[mrm]

Originally Posted by susswein

I don't have any way to measure actual lumens of output, but 2 of these puck light "felt" like the same amount of light as the thinlight, and only drew .3A total.

Human eye is quite adaptable to varying light intensity so lacking direct comparison of two light sources it is really hard to tell how much difference in light there really is.

A proper tool would be a lux meter. An acceptable substitute is a digital camera with manual program settings. If you fix ISO and aperture then the calculated shutter time will give you a good indication and a base to compare illuminance resulting from use of different light sources. An ultimate judge is you If it works for you, it is good enough (that is, unless Admiral gets involved... ).

[Cormorant]

FWIW, most smartphones these days have built-in light sensors so they can increase or decrease screen brightness depending on ambient light. There are plenty of lux meter apps available to give you a direct readout.