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This is a follow-up to my earlier question

The camera is now detected. The cable run is 120ft; this will go up to somewhere between 145 & 150ft after I put in PVC power conduits and bury it underground. The reason being critters - squirrels, monkeys, chameleons and what-not. On an earlier cable I even had birds swinging on it. That was a heavy-duty power-line rather than an ethernet cable. Another reason is ambient heat - the ambient temperature here during summer is 45C for weeks on end. For anyone curious, I am in Central India :)

Prior to installing the devices at their planned site, I used a 150ft length of Konex Category 5e to connect the Power Source Equipment, and Powered Device indoors where the ambient temperature is about 30C. The problem now is that the PD connection drops intermittently. The PSE is rated for 802.3af. The PSE cabinet of metal doesn't feel hot to the back of my hand. The PD however does feel hot - but it doesn't feel hotter than the rated 60C maximum. Infrared thermometer available here are limited to 43C so I cant5 measure accurately.

  • How should I approach this conundrum?
  • What is going wrong here - is it the device dropping the connection, or the switch?

EDIT: Thanks for the response; it does appear the cable may be the issue. At the same time though, how do I eliminate the PSE as being faulty?

EDIT: It turned out, the cable indeed was the issue but not in the way we were discussing it here on SE. My crimped connectors were at fault. I got someone more experienced, and with a younger pair of eyes to put on a new pair of connectors. The cameras were detected immediately, and have been transmitting without dropping for over two hours. I'll run them through for another five, or so before committing.

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    You have an air temperature of 45C, that would be okay if the camera is in the shade. If in the sun then quite sure the temperature will exceed 60C in no time. Make sure all connections are tight, a little wiggle might drop connection with temperature change.
    – crip659
    Commented Jun 3, 2022 at 11:25
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    You may also want to check the power at the camera for correct voltage and be sure it has no inordinate amount of noise. You have a fairly long cable run and it may not be providing clean power.
    – jwh20
    Commented Jun 3, 2022 at 12:57
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    100-150 feet (50 meters) is the limit for passive PoE.
    – MonkeyZeus
    Commented Jun 3, 2022 at 13:26
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    Does it drop in the night, or only in the daytime? Does it drop only on sunny/hot days? If looking for a potential overheating issue, looking for patterns like that would be informative.
    – Ecnerwal
    Commented Jun 3, 2022 at 15:29
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    Also, electrical interference (RFI) can cause temporary (or long-term, until restarted) disconnection. 40 meter is a long run, increasing the chance of picking up interference from anything, from lightning 100 m away, to a large electric motor starting. Even though the cable may be high-quality, there is invariably some noise pickup on lengthy runs. See if the dropouts coincide with some outside phenomenon. BTW, Starlink terminals go into thermal shutdown: arstechnica.com/information-technology/2021/06/… Commented Jun 3, 2022 at 17:00

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If you use a much shorter length of cable does the camera stay working reliably? Is it cooler to the touch when running? If so, I'd suspect it's the cable quality.

Since the device is using 802.3af and not passive PoE, it should work up to 100 meters or 300ish feet. Assuming that you're using a good quality cable for it.

You didn't link the actual type of cable you're using, so it may not be the first one that turned up for "Konex Category 5e" on google - but the one that did is 24 gauage copper clad aluminum. While you can get away with CCA cable for just data or even some short PoE runs, it's really not ideal and isn't going to work well on longer runs. It has a higher resistance that will lose more power in the wires.

For long PoE runs, the quality matters quite a bit. Thinner wires inside will have higher power losses in the cable. Those loses lead to the voltage dropping, which makes the device not work, or work intermittently, or heat up more because it's drawing more current to compensate for the lower voltage.

You also want the thickest conductors you can get. Ethernet cable usually comes in 24, 26 and 28 gauge. Some "slim" cables are as low as 30 or 32 gauge. Smaller numbers are thicker, so you want 24 or maybe 26. Outside of North America the conductor thickness may be measured in mm^2 instead - there are charts online to make the conversion if that's what the products are listed in.

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  • I tried an ultra-short length just under a metre in length - the camera was detected infallibly, and worked without interruption for nearly 48 hours at which point I killed the test. Yes, the camera did heat up though... My mistake; I didnt' realise the pairs could be CCA. The metre-marker on the cable says it is 40 Cu.
    – Everyone
    Commented Jun 3, 2022 at 18:58
  • This page states maximum current the PD should demand is 350 mA - which is about an order greater than the rated 35mA for #40 AWG Cu. Ouch.
    – Everyone
    Commented Jun 3, 2022 at 19:10
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    @Everyone It's extremely unlikely that it's 40awg wire. That's getting into the thin enameled wire you'd see inside an electromagnet or motor. At a guess I'd say that means 40% copper, which seems to be a pretty standard amount for CCA wires.
    – Grant
    Commented Jun 3, 2022 at 19:43
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    Might also be 0.40 mm diameter (though usual nomenclature uses the mm-squared value) which is 26 AWG - 0.40 mm-squared seems unlikely as that's between 21 and 22 AWG. A clear close-up of the end of a cut wire will show if it's CCA, as should a picture of the label on the box.
    – Ecnerwal
    Commented Jun 4, 2022 at 2:00
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    This one looks to be more suitable. Actual copper. Outdoor rated. 24awg. It is of course significantly more expensive. Might be cheaper similar options, i didnt look too hard. amzn.eu/d/gdErEL7
    – Grant
    Commented Jun 5, 2022 at 3:11

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