"I want to add a battery voltage monitoring device to a solar POP that I have, and I will be creating a microcontroller based circuit board with an Ethernet connection on it so I can query the device every hour to see the voltage of the battery and graph it in cacti.

HOWEVER.. my question is - I currently have the access point and the backhaul radio directly plugged into each other. So there are no RJ-45 ports for me to connect this battery monitor to.

Question is : Would a simple 2 port ethernet hub (ie just a splitter and no power usage) work sufficiently or should I put a low power consumption ethernet switch in there. I don't want to add too much of a current load just for the battery monitor. The ethernet physical layer should know how to deal with shared ethernet with automatic backoff and whatnot during a time when the battery monitor and radios want to communicate on the line - I would imagine right?"

Semaphore:
I've used splitters before for customers that were to cheap to install another Ethernet drop, or even a hub. From an electrical isolation point of view I'm sure they suck. But they work... and even a small hub draws a ridiculous amount of power.

BigCreek:
Unless I'm missing something, I don't think a splitter is going to do what you want. They're good for stuffing two Ethernet devices onto one cat5 cable but you still need the ports at the other end.

You need some type of Ethernet hub or switch to connect three devices together.

Perhaps Google for "low power ethernet switch" and see what turns up.

pmurdock (original submitter):
Basically this is what I have setup. The backhaul radio comes into a PVC box and has a female RJ-45 connector on it - which currently connects directly to 1 access point. I want in essence to "split" off that 1 female port into two female ports - (1) one for the AP, and (2) two for the battery voltage monitor. Don't really think there is a need for a powered hub is there? The cable distances are all less than 10 feet.

jdmarti1:
My biggest concern would be to create a chance for collisions on my backhaul. That is a very important link. This little unit only takes one watt. I am unsure what voltages you have on your power supply, so you either use the wall wart with this or use the 7.5v.

»www.trendnet.com/products/TE100-S5P.htm

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