Power Over Ethernet
December 27th, 2011I’m testing a sort of Gilligan’s Island mobile broadband antenna system here at our place. For whatever reason, the Telecom XT signal here has decreased in recent months. I’ve long known that all I need for a solid signal is more altitude, which I could attain by building a transceiver up on a hill that’s on our property and covering the last leg down to the house over wi-fi. While that solution would definitely work, it would require doing a solar panel/battery rig mounted up and away from the cows, mounting antennas, etc. It’s about 200 yards away from the house.
I thought I’d try something much cheaper to see what kind of results I could get closer to home. I bought a used 3g router for NZ$50. I popped in my mobile broadband modem and got it configured. That router needs 12v DC. I went with the TP-LINK TL-POE200, Power over Ethernet kit which comes with everything necessary to send juice and data over a single length of ethernet cable. I selected 12v output, plugged it all in and it worked perfectly the first time.
Next, I put the router, modem and PoE splitter in a small cardboard box and tied it to thin end of the bamboo stem. I tilted the bamboo up (about 40 feet) into the air and tie strapped the base of it to the clothesline post. I popped the ethernet cable into my switch and (lol) the signal strength doubled, and that was without using my very expensive high gain antenna!
The experiment was a success. Obviously, though, a cardboard box won’t work as an enclosure. I’m trying to think of the lightweight (and cheap) weatherproof enclosure in which to bundle the router, modem and PoE splitter. I’ve seen some Tupperware-type things at the supermarket that seem perfect, but I don’t know if those would actually keep the moisture out. The thing would have to be air tight or condensation will kill the gear.
I have frequently used 12x12x4 PVC NEMA junction boxes for almost identical applications to the one you describe.
Scepter and/or Carlon makes one that is generally available at the big box hardware stores or electrical supply houses. I know that Graybar, Antec, and Grainger carry them as well. I’m sure a local electrical supply house would have a version, even in your part of the world.
Last time I bought one the price was in the $40 or $50 range. Make sure that it has the gasket and the brass screws included.
You’ll need (flexible)sealant for the bottom penetrations and to install drip loops if any wires extend above the height of the box…etc, etc…
I’ve used such boxes to install networking equipment on self-jacking tower cranes on the oceanfront, without any ill effects on the components inside.
Here’s a randomly selected link to the item w/ pic so you know what I’m talking about. http://electrical.hardwarestore.com/14-45-electrical-boxes-plastic/junction-box-618054.aspx
Wow that junction box looks perfect. Thanks for the idea.
Something like http://www.gowifi.co.nz/mounting-hardware/abs-ip65-enclosure-240mm-x-160mm-x-90mm.html
IP65 – rating to say its protected from dust/low pressure jets of water~ safe from dust and rain 🙂
actually, condensation does not have to be a big problem where adequate ventilation and drainage is allowed.
I would avoid any translucent enclosures, due to the greenhouse effect,which would tend to encourage condensation.
@AHuxley Thanks for that link. I wasn’t aware of that place.
@Crates
Re condensation: The spec sheet on the router says, “Operating Humidity: 10%~90% non-condensing.”
The humidity is routinely over 90% here, sometimes for weeks at a time. I’ve never tried to operate something outside the upper humidity limit before, but I’m guessing that it would just fry.
Once the J-box is closed and properly sealed, I doubt you’ll have any problems with humidity. The waste heat from the electronics inside the box will tend to keep the relative humidity low and prevent any condensation.
At least, that’s been my experience with such arrangements.
You might also add some silica desiccant to the container when deploying the installation as well.