Warning about 5V LEDs

[greywolf]

I was very happy to begin with. Now however, I've had one fail so bought spares for both turn and tail lights. So far, three have failed within a few days of use out of eight total. Both 1156 and 1157 bases are involved.

[frostypuck]

I was very happy to begin with. Now however, I've had one fail so bought spares for both turn and tail lights. So far, three have failed within a few days of use out of eight total. Both 1156 and 1157 bases are involved.

Any approximate idea on how many hours those lights were burning before they failed? :confused:
Just wondering,
Chris in Boston

[greywolf]

From less than one hour to sometime within 10 hours.

[tmcgee]

Are you talking about the 5 watt Luxeons, Pat?

[greywolf]

Both the Luxeons from http://www.superbrightleds.com/ and the Eagle Eye 5 from http://autolumination.com/1156_1157.htm

I had one Luxeon go out of five and two Eagle Eye 5s out of three.

[av8or]

maybe they don't cotton to the vibrations?

[greywolf]

Two never got past a second test before installation. It had to be early electronic part death syndrome.

[tmcgee]

I had one Luxeon go out of five and two Eagle Eye 5s out of three.

Ouch. No trouble here yet. Must have been a bad lot.

I've had 4 of the yellow ones from SuperbrightLEDs in my blinkers since November 2007.

[greywolf]

That's good to know. Maybe the ones that pass the initial phase will last a very long time.

[tmcgee]

That's good to know. Maybe the ones that pass the initial phase will last a very long time.

I had the 3 watt yellows in the blinkers for about 6 months before the 5 watt ones became available. No trouble there either, but you've got me wondering if the two red 5 watters I've got sitting on the shelf are going to be okay. I bought those in April 2008 and haven't used them yet.

[RhythmScout]

strange, you musta got a bad bunch. I've had 4 amber 5W in all 4 signals for about a year. Still kickin.

[greywolf]

I haven't had a problem with an amber Luxeon yet, only the center light on a red 1157, the center red on an Eagle eye 5, and an amber Eagle eye 5 with a center and one ring LED.

[Jimding]

Might wanna check your voltage. LED's tend to be very touchy about over-voltage. Supposedly the supporting electronics will take care of this, but I have my doubts. Vibration is not supposed to be a problem, but I kinda wonder if an intermittent connection (dirty connector, slightly loose socket or connectors) might give transient voltage spikes that kill the LED's. The low current is sort of a win-lose situation, in that the low current is great for power conservation, but may not be enough to overcome a slightly loose or dirty connection. Hopefully this is just a bad batch, or statistical clumping of early-death samples. Have been tempted to jump on the LED bandwagon, but old Edison bulbs are cheap, easily replaced, and good enough, and they are relatively insensitive to power transients.

[tmcgee]

Might wanna check your voltage. LED's tend to be very touchy about over-voltage. Supposedly the supporting electronics will take care of this, but I have my doubts.

LEDs are sensitive to over-current rather than over-volatge. The only "supporting electronics" would be a current limiting resistor which is connected in series with the active devices (LEDs).

The problem would be bad LED devices or bad assembly process. The LEDs are surface mount devices.

[greywolf]

I just found this thread again so I'll post an update. Superbright just had a bad batch of red 1157 5W Luxeons. The replacements they sent me have been going strong for months and over 5000 miles.

[rebeccav]

I just found this thread again so I'll post an update. Superbright just had a bad batch of red 1157 5W Luxeons. The replacements they sent me have been going strong for months and over 5000 miles.

Are these just LED bulbs that replace halogen bulbs?

[greywolf]

1156s replace the turn signal bulbs. 1157s replace the tail/stop light bulbs. Only the headlights are halogens. I replaced the headlights with HIDs. My Luxeon LEDs are still going strong BTW. It definitely was just that one bad batch that caused a problem in the past.

[rebeccav]

1156s replace the turn signal bulbs. 1157s replace the tail/stop light bulbs. Only the headlights are halogens. I replaced the headlights with HIDs. My Luxeon LEDs are still going strong BTW. It definitely was just that one bad batch that caused a problem in the past.

Thanks - I am just starting to look into replacements for halogen and I didn't know if I had to replace the whole assembly. A plug-n-play bulb is ideal. :yesnod:

[tmcgee]

Thanks - I am just starting to look into replacements for halogen and I didn't know if I had to replace the whole assembly. A plug-n-play bulb is ideal. :yesnod:

Replacing the blinkers isn't going to save you any power because they're off most of the time. You can definitely recover some watts by swapping out the tail lights though, and superbrightled 5 watt Luxeons are the way to go.

[Arne]

LEDs are sensitive to over-current rather than over-volatge. The only "supporting electronics" would be a current limiting resistor which is connected in series with the active devices (LEDs).

The problem would be bad LED devices or bad assembly process. The LEDs are surface mount devices.

If a 'current limiting' resistor is used then an over-voltage will result in an over-current and possibly damage the LED. Using resistors this way to 'protect' a rather current sensitive device like an LED is not a good idea. If these LED's require 5V I'd strongly suggest using a small external (switching) regulator. I use an LM317 to regulate the voltage (and thereby the max current) to four 3W, 12-13VDC LED's. Overkill? Maybe, but this way I am pretty confident they will not see any voltage spikes.

[janiceclanfield]

I have the same lamps as you. I'm on my second set. The first set died within the first hour, so I called the company, and was told that there had been a "bad batch". They immediately shipped me replacements at no charge. The base colour was different, but the led's were identical.

They honour their warranty anyway...

[greywolf]

That's my situation exactly.

[tmcgee]

If a 'current limiting' resistor is used then an over-voltage will result in an over-current and possibly damage the LED. Using resistors this way to 'protect' a rather current sensitive device like an LED is not a good idea.

Every LED you buy has a spec for voltage and current. You pick the right voltage and then choose the appropriate current limiter using conservative design criteria.

If you want to use regulators, LED drivers, or even microprocessor control, go ahead. Manufactured assemblies like the superbrightleds 1156 and 1157 "bulbs" have current limiting built in already and they're designed for 12V automotive use.

[Arne]

Every LED you buy has a spec for voltage and current. You pick the right voltage and then choose the appropriate current limiter using conservative design criteria.

If you want to use regulators, LED drivers, or even microprocessor control, go ahead. Manufactured assemblies like the superbrightleds 1156 and 1157 "bulbs" have current limiting built in already and they're designed for 12V automotive use.

Yes every LED has max specs. All I'm saying is that just a resistor does not provide very good over current protection. And yes these LED's are designed for 12V operation, if this 12V provided by the car's/bike's electrical system were steady and clean and actually 12V, there would not be an issue, but it's not. I am willing to bet that every LED that does fail, failed from a preventable over current spike. The current limiting often used in these LED's is the same sillyness used in some cheap heated grips designs.