POE Injector

cranog

I am looking for a bit of advice about inline POE injectors.

I have a wireless broadband transceiver about 140 meters from the POE power source. The signal is at times unstable. I know CAT5 should not run further than 100m so will a mid-line POE injector work in this case and stabilise the signal to the router.

Is there an inline injector that is powered by the original POE at the power source?

Any advice on make and model would be appreciated.

PogMoThoin

Its not a power issue, its the fact that ethernet only works up to 100m. In reality You're sending a radio wave up the cable, after 100m it doesn't no longer recieves at the other end. You need to put a switch (or router) half way.

cranog

Thanks for the info.

What configuration do I need to do?

Router configured as an access point with line in and line out and will that bring power to the transceiver as well as signal?

PogMoThoin

Its a switch You need in Your situation, no setting up at all just pick any ports and half the price of a router. Poe must go the reciever side of the switch to send power to the reciever

cranog

Thanks for that, will get to work on it.

Maints

Have installed a similar setup to yours. The 140m cat5 is not an issue, the problem might be the voltage at the transceiver due to the voltage drop across the 140m length of cable. Measure the voltage at the transceiver and see if is within operating range. If not, or if is close to the minimum voltage, you may need to use a higher voltage psu to overcome the voltage drop.

cranog

Voltage OK. The p s unit has a 55v output. Think it needs a switch but have to lay 50m of power cable first.

mecco

Don't forget to consider moving the wireless transceiver (if possible in your case) so the run of cat5 is below 100m. It might be a solution that doesnt require more cabling and equipment. Obviously it may not be do-able depending on the wireless setup.

cranog

It's in the nearest position that has line of sight to the main transmitter 12km away.

My only other method of obtaining broadband is to set up a Tooway satellite system with all it's limitations.

mecco

Switch it is. Just said I'd point out the obvious first, just in case. Enjoy

Buzz Lightyear

What you can do is power the switch over poe. This D-Link unit is a handy way of doing it. You'll get 12 volts out the far side to power your switch.

A cheap 5 port switch will consume feck all of your power, so you could split the blue and brown pair before the switch end of the poe unit and send the remaining power to the transciever. Just make sure the wattage of the initial injector is high enough to take both units plus a bit extra. If you start to loose voltage, the current consumption will go up.

cranog

I tried a quick experiment. I put the ethernet switch between the POE unit and the router. Result.... perfect stable speeds upload and download.


transceiver.... 140m cat5........poe unit......ethernet switch....20m cat5....router

KeRbDoG

cranog wrote: »

I tried a quick experiment. I put the ethernet switch between the POE unit and the router. Result.... perfect stable speeds upload and download.


transceiver.... 140m cat5........poe unit......ethernet switch....20m cat5....router

Looking at this, you haven't reduced the collision domain to <100m, its still at 140m Is the 140m a typo?

cranog

No it's still 140m.

PogMoThoin

KeRbDoG wrote: »

Looking at this, you haven't reduced the collision domain to <100m, its still at 140m Is the 140m a typo?

He obviously had a 160m run before, just 140m from the poe

KeRbDoG

PogMoThoin wrote: »

He obviously had a 160m run before, just 140m from the poe

Turns out he obviously didn't

cranog wrote: »

No it's still 140m.

Congrats, always nice to break the 'rules' of CAT5e/6 cable running :cool: