Author Topic: Communication Distance Limits (2)  (Read 665 times)

bachphi

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Communication Distance Limits (2)
« on: February 25, 2019, 11:31:09 AM »
DavidSr,

Interesting topic, good to know. I do have a question: You said you ran a POE camera WITHOUT an injector? how does the camera get its power?

As for serial distance limit of 50FT. It's interesting that you can run up to 250 ft. However, It's not surprised that you can run longer than 50 ft with CAT5 cable , since they are twisted pair and therefore its capacitance is reduced, but I thought it should max out at 147FT.

CAT7  cable should theoretically give a max at 2500/0.36 = 6,944 ft.





« Last Edit: February 25, 2019, 11:40:47 AM by bachphi »
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DavidSr

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Re: Communication Distance Limits (2)
« Reply #1 on: February 25, 2019, 12:00:35 PM »
Great Question !
The cameras are all connected to an NVR that has a built in POE switch.

How I discovered I could run 1000' on the Ethernet to the camera was I had just bought a new camera and had a roll of cheap cat5 cable and I wasn't ready to cut it so I just grabbed both ends and put rj45 connectors on it, basically a 1000' patch cable. I hooked it up and surprised to see a perfect image, Surprised it connected at all considering not just the 300' ft limit ( 250' limit recommended by camera supplier) but I thought there would be enough voltage loss to keep the camera from powering up.

On the serial cable, I am going to experiment and see how far I can get next time I have a thousand foot roll of cat5 and I will let you know.. Or you can try and let me know...  ;)

Last night I hooked up some really old very stiff aerial phone wire to my home made anemometer. Its just a DC motor out of a CD Player. Before I did that I hooked it within a few feet of the analog input module (1771-IFE) and checked the voltage at different RPMs.


I wanted to get the anemometer up while we still had a lot of wind so I grabbed the only wire I had that was long enough. Interstingly, it worked better than expected. I saw no voltage drop - 70 feet of crappy cable no shield about 16 gauge solid.

   I have always been an outside the box person. It's a lot more interesting to see how you can make things work.

Thanks for the question!

 Have a blessed day!  and thanks for all the support you give here!


DavidSr,

Interesting topic, good to know. I do have a question: You said you ran a POE camera WITHOUT an injector? how does the camera get its power?

As for serial distance limit of 50FT. It's interesting that you can run up to 250 ft. However, It's not surprised that you can run longer than 50 ft with CAT5 cable , since they are twisted pair and therefore its capacitance is reduced, but I thought it should max out at 147FT.

CAT7  cable should theoretically give a max at 2500/0.36 = 6,944 ft.
David