Unplug LED lights 5 min before launch?

[TexasBayFisher]

Re: Unplug LED lights 5 min before launch?

Guess it depends on the MFG
I think some are purpose built boat trailer lights, while others are not.

 

[TerryMSU]

Re: Unplug LED lights 5 min before launch?

With LED lights it's very simple. If they aren't sealed to prevent water from intruding the circuit board, you can't get them wet anyways. Water will corrode the circuit board and components in no time. You can't even compare this to a bare incandescent bulb and its connection.

Heat isn't even a factor for LEDs. They don't get destroyed by heat changes from operating temps to cool temps. They become damaged by high current (which can be caused by water bridging a surface mount resister on the board).

So, you either have a sealed unit that you can just dunk in the lake and not worry about... or you have an unsealed unit that should never be wet (the bell-jar method usually = cheap lights). The mantra of 'letting them cool' only applies to incandescent bulbs.

Actually heat is a BIG factor in LED lighting. I have done some LED lighting designs for automotive interior applications. Other than that what you have said in both your posts is VERY accurate. The biggest factor that I have to deal with in moderate to high power LED designs is heat. Our designs need to tolerate 85C and run for a design lifetime of 15 years. (Not on all the time, maybe 10% if that.) I know that sounds hot, but remember your lights are right down on the black asphalt. In the case of boat trailer lights, the main issue is humidity and salt. (Well duh, as my teenager would say.) The proper type of electrical potting will keep out the humidity and salt. Unfortunately it will keep in the heat unless the design is done very carefully and that ain't cheap. In my case, I am hard on lights anyway so I buy the cheap incandescent ones. On the plus side, the LEDs themselves are very reistant to vibration, do not have any brittle glass, run much cooler than incandescent bulbs, and have a much longer potential operating life. It all depends on the system design.

Thanks,
TerryMSU

 

[ebry710]

Re: Unplug LED lights 5 min before launch?

Manufacturers don't. They want you to buy it, use it for a few years, then when one of them starts acting up go back out and buy a whole new set.
$3 worth of epoxy and some clear silicone will make them last a long time, as long as they don't get smashed.

So the epoxy doesn't effect the circuit board? That sounds good for a lot of applications.

 

[SuzukiChopper]

Re: Unplug LED lights 5 min before launch?

Actually heat is a BIG factor in LED lighting. I have done some LED lighting designs for automotive interior applications. Other than that what you have said in both your posts is VERY accurate. The biggest factor that I have to deal with in moderate to high power LED designs is heat. Our designs need to tolerate 85C and run for a design lifetime of 15 years. (Not on all the time, maybe 10% if that.) I know that sounds hot, but remember your lights are right down on the black asphalt. In the case of boat trailer lights, the main issue is humidity and salt. (Well duh, as my teenager would say.) The proper type of electrical potting will keep out the humidity and salt. Unfortunately it will keep in the heat unless the design is done very carefully and that ain't cheap. In my case, I am hard on lights anyway so I buy the cheap incandescent ones. On the plus side, the LEDs themselves are very reistant to vibration, do not have any brittle glass, run much cooler than incandescent bulbs, and have a much longer potential operating life. It all depends on the system design.

Thanks,
TerryMSU

I didn't state that heat wasn't a big deal and actually what I meant was drastic temperature changes don't affect LED lights. Going from 60C to -10C won't blow up an LED like it would a regular bulb. That is the main reason for unplugging a regular bulb is that after running for even 2 minutes they heat up and dunking them in a lake changes the temperature so much the filament explodes. The biggest heat threat for LED lights comes from high current that makes them melt down internally.

 

[SuzukiChopper]

Re: Unplug LED lights 5 min before launch?

So the epoxy doesn't effect the circuit board? That sounds good for a lot of applications.

Some epoxies do depending on the circuit. Potting epoxy is generally the best bet.

 

[ebry710]

Re: Unplug LED lights 5 min before launch?

I didn't state that heat wasn't a big deal and actually what I meant was drastic temperature changes don't affect LED lights. Going from 60C to -10C won't blow up an LED like it would a regular bulb. That is the main reason for unplugging a regular bulb is that after running for even 2 minutes they heat up and dunking them in a lake changes the temperature so much the filament explodes. The biggest heat threat for LED lights comes from high current that makes them melt down internally.

Yep. Hair thin wires don't like to be cooled down fast.

 

[CheapboatKev]

Re: Unplug LED lights 5 min before launch?

Actually heat is a BIG factor in LED lighting. I have done some LED lighting designs for automotive interior applications. Other than that what you have said in both your posts is VERY accurate. The biggest factor that I have to deal with in moderate to high power LED designs is heat. Our designs need to tolerate 85C and run for a design lifetime of 15 years. (Not on all the time, maybe 10% if that.) I know that sounds hot, but remember your lights are right down on the black asphalt. In the case of boat trailer lights, the main issue is humidity and salt. (Well duh, as my teenager would say.) The proper type of electrical potting will keep out the humidity and salt. Unfortunately it will keep in the heat unless the design is done very carefully and that ain't cheap. In my case, I am hard on lights anyway so I buy the cheap incandescent ones. On the plus side, the LEDs themselves are very reistant to vibration, do not have any brittle glass, run much cooler than incandescent bulbs, and have a much longer potential operating life. It all depends on the system design.

Thanks,
TerryMSU

Terry is right on the money..LEDs are very susceptible to heat. Any what we call "General Lighting" application (task lighting, ambient lighting, architectural lighting) LEDs have pretty massive heat sinks. One diode by it's self in a controlled cooled enviroment, no problem. But add more diodes (clusters) of LEDs to get any usable light and you have them overheating each other and in effect cannibalizing life hours.

 

[ebry710]

Re: Unplug LED lights 5 min before launch?

Some epoxies do depending on the circuit. Potting epoxy is generally the best bet.

I've never heard of potting epoxy. What is it?

 

[SuzukiChopper]

Re: Unplug LED lights 5 min before launch?

Terry is right on the money..LEDs are very susceptible to heat. Any what we call "General Lighting" application (task lighting, ambient lighting, architectural lighting) LEDs have pretty massive heat sinks. One diode by it's self in a controlled cooled enviroment, no problem. But add more diodes (clusters) of LEDs to get any usable light and you have them overheating each other and in effect cannibalizing life hours.

Massive heat changes don't affect LEDs like it does incandescent bulbs which is the situation/problem at hand. The amount of LEDs that you need to produce the type of heat you're talking about will never be found in a trailer tail light.

I've never heard of potting epoxy. What is it?

It's still epoxy but there are some mixes that are specifically made for potting applications. Just like there are different mixes of poly resin or even like you can get 5 minute epoxy or the stuff you would use on a boat application.

Here's some information on potting materials: http://www.pottingsolutions.com/

 

[CheapboatKev]

Re: Unplug LED lights 5 min before launch?

Massive heat changes don't affect LEDs like it does incandescent bulbs which is the situation/problem at hand. The amount of LEDs that you need to produce the type of heat you're talking about will never be found in a trailer tail light.



It's still epoxy but there are some mixes that are specifically made for potting applications. Just like there are different mixes of poly resin or even like you can get 5 minute epoxy or the stuff you would use on a boat application.

Here's some information on potting materials: http://www.pottingsolutions.com/

I agree no where near incan lamps, or halogens for sure
No tungsten filament burning like a welding weld..
Trailor lights, no, the DOT requirements for CBP (center beam candle power) are so low that LED's are ideal....Move them towards the front of the vehicle (headlights) and its a whole nother ball game