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Old 29-10-2013, 07:58   #46
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Re: Problems with Dr. LED Lights

I have recently puchased and installed 5 Rigid LED fixtures in my engine compartment, and focsle. They have heavy duty fixtures, the light is very bright, and the draw is low, 1 watt per unit. The only complaint is the mounting bracket is somewhat difficult to attach the light, you have to mount the bracket before attaching the light to the bracket and the nut/bolt combination is hard to line up because you have to do every thing by feel and the nut is loose so it can get cross threaded. Once mounted, I love them, time will tell if they will last.
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Old 29-10-2013, 08:58   #47
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Re: Problems with Dr. LED Lights

Well it's been more than 3.5 years since my original post on this thread. In the meantime, in order to reduce my electrical load I did buy Dr. LED anchor and running lights. In two years of ownership 2 of the original four bulbs have failed. The anchor light was the first to go, but as it was used nearly every night for over a year it probably had 4000 or more hours on it. The second to go was my port running light. It probably only had 200 hours on it as I don't do that much night travel. All-in-all much less life than one would expect from the claims and for more than $40 a bulb pretty expensive.

The note about only being certified for power boats is interesting. As the owner of a non-heeling sailboat I wonder how the USCG would treat it. My guess is that as bureaucrats they would go by the letter of the law. Of course I guess It would only apply to my starboard running light from the quotes supplied. Maybe I'll just have to engage an engine when the Coasties come by.

I have noted radio interference from the anchor light, but oddly not always. I have also found that sometimes cycling the power to the anchor light will stop the interference. I can't explain it, I just report it. I don't seem to get any interference from the other lights, but then again they are located some 60 feet from the antenna
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Old 29-10-2013, 10:51   #48
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Re: Problems with Dr. LED Lights

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Originally Posted by Dockhead View Post
I've been using various LED units -- G4's and festoons -- for nearly three years. Nary a problem with any of them except for two Superbright LED units which exploded when first powered up.

I intentionally tried a variety of them from super cheap (but still, buck regulated, of necessity since I am 24v) to super expensive, and found them all to be good, except the two mentioned before.

Did not try any Dr LED, but this should be relevant to the general topic of reliability of LED lighting.
This is my experience too, you need to look at each design specifically, Ive had "expensive" ones fails and cheap ones last forever, I suspect the expensive ones are just cheap ones with more markup !

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Old 29-10-2013, 11:48   #49
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Re: Problems with Dr. LED Lights

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Originally Posted by Captain Bill View Post
[...] I have noted radio interference from the anchor light, but oddly not always. I have also found that sometimes cycling the power to the anchor light will stop the interference. I can't explain it, I just report it. I don't seem to get any interference from the other lights, but then again they are located some 60 feet from the antenna
The interference is probably drifting around in frequency, depending on the battery voltage, and temperature. Depending on what frequency / channel you are listening to you may or may not hear it. This interference is usually a "comb" of noisy signals, with these signals spaced a few hundred kilohertz apart (the spacing depends on the switching regulator design). The fundamental frequency and harmonics (the comb) shifts as your battery charges and discharges, as the outside temperature warms and cools, and as the switcher components warm up.

When checking for interference, I try to listen to all VHF channels, and as many SSB frequencies as I can. It can really be a moving target, and this is one reason why people have a hard time knowing if they have a problem, or a solution.
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Old 29-10-2013, 13:22   #50
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Re: Problems with Dr. LED Lights

I have posted this on here before. If you read the spec sheets for LEDs you will find that the volt swing from 12 to 14.4 on a typical boat is too much by about 2 times. They are very prone to fail if the voltage is not steady.
I have used Dr LED bulbs about 2 years with no failures. I did build and install a voltage reg in the circuit. Holds the voltage at a constant 12 volts. Cost about $5.00 to build. Is not a part of the bulb so if one does fail the volt reg is still there for the next one.
One instance does not a scientific study make but when taken with the info on the spec sheets it does indicate the problem.
Not a part of Dr LED or do I have an interest. Just pointing out all these products that do not have a voltage reg built in (read most) can benefit from one.
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Old 29-10-2013, 13:37   #51
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Re: Problems with Dr. LED Lights

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Originally Posted by svadagio View Post
I have posted this on here before. If you read the spec sheets for LEDs you will find that the volt swing from 12 to 14.4 on a typical boat is too much by about 2 times. They are very prone to fail if the voltage is not steady.
I have used Dr LED bulbs about 2 years with no failures. I did build and install a voltage reg in the circuit. Holds the voltage at a constant 12 volts. Cost about $5.00 to build. Is not a part of the bulb so if one does fail the volt reg is still there for the next one.
One instance does not a scientific study make but when taken with the info on the spec sheets it does indicate the problem.
Not a part of Dr LED or do I have an interest. Just pointing out all these products that do not have a voltage reg built in (read most) can benefit from one.
Bob
Maybe you're protecting the electronics, but you're not protecting the LED.

Stolen from #57 LED Anchor Light

You didn't need to do that for Dr LED. As others have stated many LEDs have built in circuitry. At boat shows he used to have a variable voltage power supply that he would crank from low to high voltages, had an ammeter showing constant current consumption over the entire range and no change in light output.

From page 23 of http://www.doctorled.com/DrLED_Marine_Catalog_0911.pdf

Internal circuitry provides for constant current consumption, regardless of voltage fluctuations from the source (11
to 15 VDC), meaning no flickering and longer LED life
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Old 29-10-2013, 13:55   #52
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Re: Problems with Dr. LED Lights

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Originally Posted by svadagio View Post
I have posted this on here before. If you read the spec sheets for LEDs you will find that the volt swing from 12 to 14.4 on a typical boat is too much by about 2 times. They are very prone to fail if the voltage is not steady.
The two things that kill raw LEDs are: reverse voltage (instant death; even static can kill a LED) and overcurrent (shortened life, overheating).

Any LED light fixture or bulb replacement intended for automotive or marine use should be able to work effectively from about 10 to 15 volts, and should be protected from reverse voltages, transients and overcurrent within the above operating range. If they don't, they're not ready for prime time.

Even with just a series dropping resistor, it's just a matter of choosing a resistor that keeps current at 15V under the LED's rated max current. Easy. The LED assembly manufacturers should be on top of that, as well as protection from reverse voltage and transients.

The more advanced LED assemblies with active regulation can often take between 10v and 30v input without problems. So an additional regulator shouldn't be necessary.

Just sayin.
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Old 29-10-2013, 14:32   #53
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Re: Problems with Dr. LED Lights

LED's are also very susceptible to power spikes. A good marine light will have surge/spike suppressors as well as current regulation and of course noise shielding/suppression.
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Old 29-10-2013, 14:50   #54
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Re: Problems with Dr. LED Lights

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Originally Posted by Maine Sail View Post
Which bulb are you referring to? I have the IMANNA labs certification reports right here in front of me.

WHITE - Here is the summation for the Aquasignal Series 40 All Round White with Polarstar 40 white LED bulb:

"7.0 COMMENTS AND OBSERVATIONS
The data from these tests show that the Aqua Signal Series 40 AAW navigation light meets the requirements of the standards listed above for sail or power driven vessels under 20 meters in length when equipped with the Dr. LED replacement LED light source. Test equipment used in the performance of these tests was calibrated to standards traceable to the N.I.S.T. The results of the tests presented herein apply only to the test specimen as prepared and as tested."


RED - The red Polarstar 40 bulbs say this:

"7.0 COMMENTS AND OBSERVATIONS
Test equipment used in the performance of these tests was calibrated to standards traceable to the N.I.S.T. The results of the tests presented herein apply only to the test specimen as prepared and as tested. The data from these tests show that the sample tested meets all of the performance requirements of the standards listed above for sail or power driven vessels under 20 meters in length."


GREEN = But the green Polarstar 40 bulb says this:

"7.0 COMMENTS AND OBSERVATIONS

The data from these tests show that the sample tested meets all of the requirements of a two mile light specified in the standards listed above for power driven vessels 12 to 20 meters in length."



Seems like only the Polarstar 40 red and Polarstar 40 all round white have approvals on for use in Aquasignal Series 40 fixtures for sail boats.

I find it odd that people assume getting a nav light certification is easy. Here we have only a color change from red to green, in the same LED bulb, by the same manufacturer, and we lose sailboat certification on green but not on red....
Well as they say: the proof of the pudding is in the tasting. So, I measured the vertical sectors myself. I obtained a new red Dr. LED Polarstar 40 all-round red LED (model 8001764) and installed it in a new Aquasignal Series 40 fixture.

I then mounted the light vertically and projected the light on a wall. There is a distinct cut off of light that produces a dark shadow. At that shadow, the light is nearly zero - not the required 50% brightness. That shadow is caused by the edge of the conically shaped reflector inside and at the top of the LED assembly. I tested with the fixture lens on and off, and found no significant change in the location of the shadow (vertical cut-off). The fixture's Fresnel lens is obviously designed to focus the diffuse light from an incandescent lamp - not a point-source light from an LED.

The distance to the wall from the center of the LED was 42 units. The height from the center of the LED to the shadow produced by the LED reflector was 16 units. The ratio is 47/16 = 0.340. The arc tangent of 0.340 is 18.8 degrees.

18.8 degrees does not meet the COLREGS requirement for sailboats. The requirement is 25 degrees.

The only way to obtain the required light intensity from a single LED consuming less than 2 watts is to concentrate the light in a narrow vertical band using reflectors. Unfortunately, that concentration is too tight for sailboats.

What does this mean? It means: if your boat heels past 18.8 degrees, your LED light will vanish on the side towards which it heels (downwind). For any reasonable person, the whole point of having the lights is collision avoidance - not regulatory requirements. But if you have an accident, this issue is likely to come up, and the responsibility for complying with COLREGS rests with the skipper/operator, not the manufacturer (although you may have some civil recourse if the manufacturer misrepresented their product).
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Old 29-10-2013, 15:06   #55
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Re: Problems with Dr. LED Lights

Cal40John
I cut a Dr LED apart and found only a dropping resister. Do a little math and you will find that does not meet the requirements. It does not limit the swing in voltage. It only reduces the voltage. You can not reduce the voltage enough to light the LED at the low end and limit the current at the top end. It is probable better than nothing but still a short life.
As someone else said a constant current driver is the way to go. I do not know which manf. do this so I went with a voltage reg that holds the voltage at 12 volts. Now I can use anybody's bulb.
Bob
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Old 29-10-2013, 16:56   #56
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Re: Problems with Dr. LED Lights

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Originally Posted by svadagio View Post
Cal40John
I cut a Dr LED apart and found only a dropping resister. Do a little math and you will find that does not meet the requirements. It does not limit the swing in voltage. It only reduces the voltage. You can not reduce the voltage enough to light the LED at the low end and limit the current at the top end. It is probable better than nothing but still a short life.
As someone else said a constant current driver is the way to go. I do not know which manf. do this so I went with a voltage reg that holds the voltage at 12 volts. Now I can use anybody's bulb.
Bob
I've seen him at boat shows with his variable source and no change in current. You could accuse him of demonstrating something that he wasn't actually selling, but then it makes it hard to understand the several people that have reported RF interference from their Dr. LED bulbs. RF interference isn't going to come from a dropping resistor, it's going to come from a switcher.
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Old 30-10-2013, 12:08   #57
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Re: Problems with Dr. LED Lights

So here's the scoop directly from Dr. LED....

First my response, then following is their answer to my report:

-----------
Date: Wed, Oct 30, 2013 at 11:05 AM
Subject: Re: USCG Colreg Cert
To: customerservice@doctorled.com


Thank you. I will return the product to the vendor.

I am puzzled by your response since the brightness output requirements are the same for both powered and sailing vessels.

I recommend measuring the vertical sectors. My measurement shows the light being cut off entirely at 18.8 degrees referenced to the axis from the center of the LED to the top internal reflector.

Since this could adversely impact safety at sea, how do you plan to communicate this issue to vendors and the boating community? There currently is no labeling that I can find that indicates the LEDs are not certified for sailing vessels.


On Wed, Oct 30, 2013 at 10:26 AM, Dr. LED Customer Service <customerservice@doctorled.com> wrote:
Hi Patrick,

You are right that our red and green bulbs are certified for power vessels only for the time being. The reason being, red and green LEDs were not as bright as white LED in terms if lumen output. We can certainly improve the bulbs in our next production runs. For your information, the while bulb is certified for use with sail and power vessels as the lumen output is higher.

Yours truly,

James
for Dr. LED
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Old 30-10-2013, 16:02   #58
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Re: Problems with Dr. LED Lights

Since there are no published RFI standards for LED lamps, and very little published test results, I decided to run my own tests.

Before sending it back, I looked at the RFI from the Dr. LED lamp on an Agilent N9342C spectrum analyzer. This is a $20K laboratory instrument, which your average sailor wouldn't have on hand. I also have a Faraday screen room to reject outside RFI. The background noise over the 2 to 200 MHz spectrum was -90dBm inside the screen room.

The Dr. LED lamp produces a lot of RFI in the 42 MHz region: 30 dB above background (-60 dBm). It also produced very significant RFI between 140 and 170 MHz (-65 dBm). It was fairly quiet (-72 dBm) in the HF band (3 to 30 MHz). However, if you place it anywhere near your VHF antennas, expect your receiver to be de-sensitized. You might have to turn the squelch all the way up. If you place it near an AIS antenna, expect the range of received vessels to drop to nearly nil. Not good, if you're depending on AIS for collision avoidance.

I tested one other LED: the Superbrightled model 1157-R45-T, which is intended as a replacement for the tail light/brake light on automobiles. It is in the same BAY15D base (1157) as the Dr. LED product, and fits the Aquasignal model 40 fixture. I measured a draw of 160 milliamps (0.16 amp). The wiring is different since it is intended to be used in a "dual brightness" configuration. Connect negative to the plug base, and positive to whichever of the two center contacts provides the highest output.

The superbrightled has 45 separate LED emitters, and it is MUCH brighter than the Dr. LED lamp. It also costs about half as much ($24.95). It produced about the same amount of RFI at 42 MHz, but no measurable RFI in the 140 to 170 MHz VHF spectrum. Cheaper, quieter, brighter.

Both LEDs will probably cause interference in the HF band. The Dr. LED will probably wipe out your VHF receiver and AIS if it's anywhere near the antenna.

The RFI problem with all of these LEDs is caused by the "feature" that allows them to operate over a broad voltage range: they use switching power supplies to accommodate that broad voltage range -- that become all-band radio transmitters when poorly designed. The manufactures want to sell their product to as many customers as possible, and the wider voltage range permits that. The only benefit to the customer is a constant brightness down to a low drop-out voltage (usually around 9 volts). But we all have lived with incandescent lamps that dim as the battery voltage diminishes, and it wasn't that big of a problem.

The easiest way to solve this RFI problem is for LED manufactures to offer LEDs that are -- just like their incandescent predecessors -- designed to operate at just one voltage (plus or minus a volt or two) to eliminate the switching supply.

But the hucksters market these LEDs to us poor punters with the hype that they will work over fantastic voltage ranges - as if that's actually a feature - when in fact it just makes for savings in manufacturing costs by eliminating the need to make multiple models for multiple voltages.
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Old 30-10-2013, 17:41   #59
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The main reason switch mode is used is to reduce heat generation


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Old 30-10-2013, 19:04   #60
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Re: Problems with Dr. LED Lights

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The main reason switch mode is used is to reduce heat generation


Dave
Yes, a switching regulator both reduces heat generation and improves efficiency over an analog regulator BUT - if the LED lamp is designed for a single voltage - it needs neither. An LED lamp designed for 13 volts +/- 2 volts needs only a series current-limiting resistor. And it will produce zero RFI.

For example. If you have an array of four red LEDs with the typical voltage drop of 1.7 volts each wired in series, a design current of 20 milliamps, and a supply voltage of 12 volts, you need only one 260 ohm series resistor as a current limiter. That resistor will dissipate (waste) only 0.1 watt. If the voltage rises to 15 volts, the current will increase to 32 milliamps. So specify LEDs rated at 40 milliamps, and you're done. No RFI, and a component count of five.

I'd add an electrostaic discharge diode rated at 15 volts in parallel to protect the LEDs. A 1N6275AG diode will work just fine. (Connect the cathode to the positive supply line.) It'll cost you 30 cents at Allied Electronics.
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