sealing compounds

[petersonra]

I am looking for a product i have seen used but cannot think of the name off hand.

It is a pressurized can of sealant (much like foam insulation in a can) that can be used to seal off a conduit or other hole with wires running through it to prevent liquid transmission.

Any one know what i am talking about?

What I have is a conduit knockout with a plastic bushing with some wires going through it, and I am afraid water might drip down on the wires and enter the cabinet so i want to seal the hole.

[busman]

If you mean the expanding polyurethane foam; around here the brand is Great Stuff and it comes in the original formula and a waterbased. I have not had good luck with the waterbased and I don't know if either is acceptable for use in direct contact with insulation or cable sheathing.

Mark

[hardworkingstiff]

I'm curious, what is this application? Outside box and the conductors are exiting the top of the enclosure?

[chelectrical]

I have also been looking for a product that seals conduits (around wires)from water leaks. Also, any suggestions for sealing around SEC going into the house from the meter. I've been using duct seal but I'm sure there must be something better out there. Maybe just silicon.

[petersonra]

I emailed Dow. They said great stuff pro foam is ok for wires and is supposedly waterproof.

they did caution against letting it touch bare wires.

i also found this stuff

http://www.arncocorp.com/Product.aspx?PAGE_ID=242

[tom baker]

The sealing product can not damage the wires. 300.7(A) requires an Approved Product. Check with your AHJ.

[petersonra]

I don't see how 300.7(A) applies to this case.

I am not worrried about condensation, nor is this a case of a raceway transitioning into a building.

[iwire]

You may be right that 300.7(A) does not apply.

I believe 110.12 does.

Beyond that I have not found any product that effectively seals around conductors. (The expanding foam does not work)

IMO The best ways to deal with it are the following.

Do not enter the top of the enclosure.

That is a local requirement with Fire Alarm Master Boxes.

Put a conduit "T" in just above the enclosure, pack your sealing compound in their and let the T work as a drain piped around the enclosure.

Water is tough to keep out if you have gravity working against you.

[mdshunk]

I'm thinking that Chico A sealing compound and Chico X filler or EYC sealing compound and EYF damming fiber work pretty well. It might be a little too permanent.

[tkb]

I found a couple of sealing methods.
I have never used them.

Cable Seal (http://www.cableseal.com/)
Rayflate (http://catalog.tycoelectronics.com/TE/bin/TE.Connect?C=19998&F=0&M=CINF&GIID=2110&LG=1&I=13)

[iwire]

Hi Tim, I have tried the Rayflate devices before, well actually Scott S. put them in, I went back later and had to pull them out.

They did not stop the water entering the switchgear of a very large house in Dover. I think you can guess who's house that was. :D

[macmikeman]

If you are sealing around ser cable where it enters a wp compression connector at the top of a meter socket, use duct seal. If you are sealing a penetration of ser cable thru siding why not just use dap caulking, or one of the even better expensive sealant brands?.