Outdoor Wirless Enclosures

[phillip.vansickle]

Does anyone have any experience with outdoor wireless enclosures?

I am looking at polycarbonate NEMA 4X enclosures....these are totally sealed.

The environment that these would be working in ranges from -20 to 110 degrees with very low humidity.

Would vents or weep holes be a good idea?

What about fans or heater strips?

I am concerned about moisture accumulating in the boxes...

[George Stefanick]

Well it depends. What type of AP are you going to use. Have you looked at the 1500s, these dont require a NEMA, but are $$.

As for sweating, yes thats always a concern. You should pull the spec of the ap you plan to use and see what temp limitations it has. Then knowing the environment, this would determine if you need a fan / heater. NEMAs decked out with fans and heather get pretty $$$. You also need to consider powering the NEMA as well and that comes at an addiitonal expense. 

[phillip.vansickle]

I agree on the 1500s...but they are way too expensive...and I dont need to do mesh.

I want to use 3602E APs, Terrawave NEMA 4X 14x12x6 enclosures and Terrawave 6dbi 4pack Omni and Pannel antennas. I've already tested these APs with these antennas and it works beautifully.

Heater strips are an option with these enclosures and don't cost all that much....running 110 to each AP is very possible, but a lot more work....and another penetration into the box..

The AP spec goes from -4 to 131 degrees operating....

[George Stefanick]

Only one way to test it out. Get one run it in the neviroment and see what happens.

But I think you will be ok with a simple NEMA without heat and fan. Unless you go below the -4. As you mentioned -20, right ...

I have about 100 1242 in NYC in a simple plastic nema box. No vent, no heater, no fan. In the last 2 years only 1 died.

[phillip.vansickle]

I have access to an environmental test chamber.

I tested a 3602 for over 24 hours at -40 degrees and for over 24 hours at 125 degrees...

The AP worked just fine the entire time.

I don't think temperature wold be an issue here...just moisture.

Has moisture in sealed enclosures been an issue in your 1242 deployment?

[George Stefanick]

Very nice ...

No we took a peek on them 6 months and a year later and all was good. We did notice, (10 nemas) did have fans, we purchased these first prior to the roll out. These were considerably dirty on the inside. The filiters didnt hold up.

As for moisture, no they were ok. Just make sure the seals are soild and tight. Normally the antenna holes are the ones that come into question. Add extra calk on these ..

[phillip.vansickle]

Well,

I settled upon a solution.

I used Gore protective vents. These are gas oleophobic/hydrophic membrane vents.

Basically, they allow gasses to pass through, but not water or oils.

They prevent the container from developing a suction due to expansion/contraction and drawing in moisture past the seals.

http://www.gore.com/en_xx/products/venting/protective/problems/protective_vents_problems_solved.html

Sealing Devices, Inc , is a distributor that deals in small quantities of these vents.

Send the engineer on staff the measurements of the enclosure, and approximately how much space will be taken up by equipment within it. The engineer will recommend a vent for your enclosure.

I had two varities to choose from, a stick on vent, or a screw in vent with a backing nut. I chose the screw in vent.

Simply drill the proper sized hole on the side of the enclosure, carefully debur it with a razor blade, install the vent, coating the threads with Loctite (they make a cyanoacrolate version for plastic threads) and install the backing nut. I use a socket and just snug the nut on with my fingers (do not use a rachet...you will overtighten it).

I tested the enclosures by sumberged them in water, and spraying with a garden hose...no leaks.

So far, I have not had a moisture problem....we will see in a year or two if every enclosure stays dry.

I am of the belief that they will.

[phillip.vansickle · Accepted solution]

The vent is visible on the side of the enclosure

(PMF100520 and backing nut M10510007...the particular vent is tied to the volume of the enclosure) :

Inside view of the enclosure. Tessco 14 X 12 X 6 Polycarbonate.

I ordered the boxes with heater strips just in case I needed them at some locations.

The price difference was not that much, and it would have been far more work to retrofit the box in the field, rather than just run AC to it if it needed it.

Fan thermostat was left in place but I doubt these would ever be used,

I had to relocate the heater strip, fan thermostat and terminal block in order to make room for the AP.

I just removed the backplate and drilled and tapped new holes.

The enclosure can be custom drilled if requested.

An electrician came up with this universal mounting bracket made up of 1 5/8" unistrut.

These are easily made for a few dollars each using a wire feed welder.

This bracket will mount easily to the side of a metal, cinder block, wood, or concrete building.

It will also easily mount to a telephone pole or a metal pole (using straps available at any electrical supply place).

The eclosures need the optional 12" wallmount kit (few dollars extra) to mount securely to the bracket.

      

The bracket being mounted.

Completed, mounted with PoE lightening arrestor.

I used 4 Terrawave 0-6GHZ lightning arrestors and a Transtector gigabit PoE lightning protector (1101-959) for each AP.

Belden shielded outdoor UV/Oil Resist CatVE cable with shielded connectors was used for the cabling.

Overall, I think it worked out quite nicely. The coverage is excellent.

Omni Antenna:

http://www.terra-wave.com/shop/files/products/antennasb/80211n-mimo-antennas/24-ghz-mimo-antennas/24-ghz-mimo-outdoor-omnidirectional-antennas/2%204_5%20GHz%206%20dBi%20Outdoor%20MIMO%20Omni%20Antenna%204%20Leads_M6060060MO1D43602.pdf

Patch Antenna:

http://www.terra-wave.com/shop/files/products/80211n-mimo-solutionsb/80211n-mimo-antennas/multiband-mimo-antennas/24--5-ghz-mimo-antennas/24--5-ghz-mimo-patch--panel-antennas/2.4_5%20GHz%206%20dBi%20MIMO%20Quad%20Patch%20Antenna_M6060060MP1D43602.pdf

I'm not endorsing any products here...just sharing what worked for my situation.

[George Stefanick]

Loooks great! nice job!

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"Satisfaction does not come from knowing the solution, it comes from knowing why." - Rosalind Franklin

[Rob Huffman]

Hi Phillip,

I agree with George, nice work here and thanks for this very detailed post

Much appreciated.

Cheers!

Rob

"May your heart always be joyful
May your song always be sung" - Bob Dylan

[George Stefanick]

Phil,

I run a blog and if you would be intersted in doing a blog post I would be happy to post it  ... This could help others ..

www.my80211.com

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"Satisfaction does not come from knowing the solution, it comes from knowing why." - Rosalind Franklin