Conformal coating vs Potting Epoxy ??

[ixfxi]

With the use of LED lights booming lately, especially in the automotive industry.. I am seeking a solution for weatherproofing the LED circuit board arrays we build. Currently, we have been using a silicone conformal coating which is clear and does a decent job of protecting the circuit boards from the elements. However, is there such thing as a spray on coating which is 100% weatherproof?

Sometimes, a light assembly can fill with water due to faulty seal or gasket, and its important that our LED arrays are fool-proof and protected under all circumstances.

There are two different LED arrays we work with, one is standard fiberglass circuit board which is not flexable. We have been considering potting these with epoxy, but still want the ability to make repairs. Epoxy is very difficult to remove.

The other type of circuit board is flexible and white in color, and needs to be aesthetically pleasing. We are looking for a transparent coating that will allow the board to be submerged under water. It is important that the coat be flexible.

Is there such a beast?!?! Please help.

 

[carnage1]

I believe there are some sprayable conformal coats as some boards I have worked on appeared to be sprayed by the customer.
Please do your techs a favor and don't use potting epoxy, it is horrible stuff.
Why spray on?

 

[ixfxi]

It doesnt necessarily need to be spray on, but I figure that application would be easier to apply.

The most recent coating we will be testing with is listed as a Corona Coating made by MG Chemicals. It can be applied via brush or by dipping. I hope this provides better results.

The most important features are:
- water clear and will not yellow
- flexible
- circuit board protection from being submerged in water

I really do not want to pot the products with epoxy, especially since repairs are so difficult. I am hoping there are better solutions.

 

[sreid]

Try contacting Humiseal. They've been around for years and have a wide range of coatings.

http://www.humiseal.com/coatings.htm

 

[MacGyverS2000]

Silicone dip is the way I've been going for the last few years. Yes, reworks are a PITA, but I'm proud to say the high quality of my designs has limited those to very small numbers The spray solutions won't easily cover under ICs, so be aware, nor will they protect against the occasional abusive user attack during installs (like a pencil jab) as well as silicone will. If you go the spray route, expect to use several coats for quality environmental protection, and I can't say if complete submersion will be taken care of with sprays.

I'm interested in what you come up with, though...


Dan
Owner

http://www.Hi-TecDesigns.com