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What voltage is the PoE hardware injecting onto the cable? It is usually 12V DC or 24V DC.
12 volt DC, to power a 12 volt cable modem.
Thank you. Is the wire the usual 26 AWG copper wire?
Cat 6 direct-bury wire is what I'll be using.
That is usually 26 or 28 AWG, so we will use 26 as the wire gauge which is slightly larger than 28 AWG.
250 feet is far outside the capacity of PoE power in this situation. One moment and I'll bring in an image of the power calculator.
(click anywhere on the above image to view it at full scale)
The remote access point will pull at least 1 amp of current, so PoE won't do the job in this case.
Thank you. In that case I will have to run a 110v power cable to the road.
Would you like me to calculate the wire gauge necessary to run DC power on a separate cable for the remote AP?
(My guess is that it's going to be around 12 AWG to 14 AWG, which is the diameter used for normal house wiring)
Yes, you could just barely do it with 14 AWG cable. The voltage drop would still be 10%, but it would probablywork.
No need. I may as well commit to running a 110v direct-bury cable so I can also power environmental controls in the enclosure itself.
However, if you're going to be burying 12 or 14 AWG cable, it makes more sense to run 110 on it as the resistive losses will be far less.
Yes. Is there a minimum distance between the 110v cable and the data cable to avoid excessive interference? Obviously they will both need their own trench.
Other than this issue, the solution you've proposed is workable.
Excellent. Thank you for your time.
There won't be any significant interference between the AC cable and the data cable, though I recomment putting gas arc suppressors on both ends of each to prevent induction voltage spikes from any nearby strikes.
Ah, noted, thank you.
I would recommend enclosed flat-panel antennas at both ends, which should give you about a 12 to 14 dBi gain over omnidirectional antennas. These are readily available on ebay and on most internet networking suppliers. Figure $40 to $60 each.
Okay. And 802.11n would be preferred for this application if I go with a wireless network bridge?
The reason I've recommended gas arc suppressors is because there is very little effect on the signal quality until they arc over. The more common MOV surge arrestors act like capacitors, which is not an issue on the AC side but is definitely an issue on the network side.
... I need to look up the frequency allocations for a/b/g/n to give you a correct answer for that one. Please bear with me a moment.
I would recommend staying with b or g. The reason for this is that b and g run in the 2.4 GHz spectrum while a and n run in the 5 GHz spectrum. The shorter the microwave, the more chance that there will be a problem in rain, snow or damp conditions.
802.11n is allocated both 2.4 GHz and 5 GHz spectrum, but I don't know how it is handled in the case of transmission problems.
Ah, okay. With flat-panel antennas it won't be an issue anyways.
I'm satisfied with these answers. I feel you've provided more detail then was originally requested; I will up compensation accordingly.