Long outdoors netwok cable run

TonyR

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Also I want to remind everyone Data Ethernet runs do not have a ground and the only ones that get knocked out are POE runs because of the brown pair being grounded to a power supply.
That may have been your experience but it differs significantly from mine. I have had MANY data-only Ethernet cables buried and aerial outdoors between buildings pick up extreme ESD from nearby lightning strikes, damaging network devices on one or both ends.

The above hard-wire links were replaced with Engenius (2007 to 2012) and later Ubiquiti (2012 to present) wireless bridges. All 10 of the wireless bridges have been in place and operating close to 12 years with no issues attributed to lightning except one 1/2 of a Engenius bridge did get damaged; that link was replaced by Ubiquiti NSM2 Locos about 8 years ago and is going strong.

FWIW, the lighting in NW AL can often be as fierce as that in neighboring Florida.
 

tigerwillow1

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1500 feet is the longest data run possible with Cat5e/6 cable.
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Also I want to remind everyone Data Ethernet runs do not have a ground and the only ones that get knocked out are POE runs because of the brown pair being grounded to a power supply
Where does the 1500 feet come from? Every source I've found says 100 meters, about 328 feet, is the maximum for standard ethernet. And that brown pair info wouldn't apply to runs from a PIOE switch because the brown pair isn't used for power in POE Mode A.
 

jnissen

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Isolation transformer was key to enabling that lightning protection. I'd run similar lengths with copper and those isolation transformers are a necessity.
 

MTL4

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Where does the 1500 feet come from? Every source I've found says 100 meters, about 328 feet, is the maximum for standard ethernet. And that brown pair info wouldn't apply to runs from a PIOE switch because the brown pair isn't used for power in POE Mode A.
I agree, 1500ft is definitely well into fiber territory distance wise.
 

tech_junkie

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Where does the 1500 feet come from? Every source I've found says 100 meters, about 328 feet, is the maximum for standard ethernet. And that brown pair info wouldn't apply to runs from a PIOE switch because the brown pair isn't used for power in POE Mode A.
The cameras I took apart are POE B mode even though they connected at 100Mbps.
Eventually I imagine all ip cameras will be 1Gb connections as 100Mbps has aged into obsolescence.
But regardless if the orange pair or the brown pair is used its still grounded to a power supply.
 

tech_junkie

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Isolation transformer was key to enabling that lightning protection. I'd run similar lengths with copper and those isolation transformers are a necessity.
I decided to do that since the POE power supply was a two prong power with a Y capacitor connected from DC ground and AC Neutral and I wanted a higher impedance than that so lightning wouldn't travel into the circuit as it will seek the path of least resistance.
 

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I agree, 1500ft is definitely well into fiber territory distance wise.
One thing I do notice over the last 5 years is fake cat5/6 cable that is aluminum alloy instead of pure copper and they don't make good long runs. However I probably couldn't do it with UTP wire.
 

TonyR

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.......because of the brown pair being grounded to a power supply.
But regardless if the orange pair or the brown pair is used its still grounded to a power supply.
Are you saying that either conductor in the UTP is "grounded" (as in "earth ground") if being fed by the DC minus side of a POE power supply?

The term "ground" as in AC house wiring and the "ground" (negative) in a isolated DC system are not synonymous.
 

MTL4

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One thing I do notice over the last 5 years is fake cat5/6 cable that is aluminum alloy instead of pure copper and they don't make good long runs. However I probably couldn't do it with UTP wire.
I totally agree, not a fan of CCA cables at all. Same reason why you need to upsize conductor size when you run aluminum electrical wiring. At least the high voltage aluminum stuff is heavily regulated so you know what you're getting vs some of the el cheapo CCA junk on the market.

You mentioned a CAT5/6 1500ft run though, was that a typo? I don't see any copper cables spec'd to be capable of anywhere near that distance. Are you talking about just using it like a POE injector for power and not using it for data transmission?

img9.jpg
 

jnissen

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CCA cables are all over the place and work (temporarily IMHO) for short hauls. Anything over 100M should not attempt to POE or wire in general. That’s the real advantage fiber offers.

That being said I did run about 350 feet of cat6a wire in a water line trench as a backup solution in case my fiber didn’t work out. I had a partial spool of CAT6A copper bury rated cable so tossed it in. Haven’t looked at it since. Worst case it’s a tracer wire to detect where the water line runs!


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TonyR

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Excerpt from TrueCable:
  • CCA is not approved for use by ANSI/TIA in Ethernet cable applications due to poor data and PoE transmission characteristics
  • CCA is not approved for use in any application by the National Electric Code (NEC) for low or high voltage cabling due to it being a fire hazard
  • CCA is not approved by UL due to it being a fire hazard

And from Belden, CCA Cable: 5 Reasons To Stay Away:

 

tigerwillow1

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The camera does not determine what POE mode is used, the end supplying the power does. POE switches use mode A, and have no need or reason to connect anything to the brown and blue pairs on 100 mbps ports. The camera is required to support both modes to be 802.3 POE compliant. Cameras might support gigabit in the future but aren't even close to having the need.
 

tech_junkie

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You mentioned a CAT5/6 1500ft run though, was that a typo? I don't see any copper cables spec'd to be capable of anywhere near that distance. Are you talking about just using it like a POE injector for power and not using it for data transmission?
The wire I used was Beldon 9892 by my install records. Which was a install at a shopping mall.
I have used 22ga cat5e CMX wire before as remote power wire for switches The 450ft run was the longest run I did that with. Which I used half the wires for + and the other half as - (which was the install in post #20 )
 
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tech_junkie

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The camera does not determine what POE mode is used, the end supplying the power does. POE switches use mode A, and have no need or reason to connect anything to the brown and blue pairs on 100 mbps ports. The camera is required to support both modes to be 802.3 POE compliant. Cameras might support gigabit in the future but aren't even close to having the need.
The port does that when you plug it in and it first test is to see if pins 4&5 are shorted, then it checks if 3&6 are shorted as well as pins 7&8 to see if its shorted so it would apply power appropriately.
I could probably could dig up the POE controller ic datasheet to show you how that operates on the hardware level..
The device is preset to whatever POE power scheme it uses, and the port it plugs into (switch or router) senses if it is type A or type B
 

MTL4

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The wire I used was Beldon 9892 by my install records.
I have used 22ga cat5e CMX wire before as remote power wire for switches The 450ft run was the longest run I did that with. Which I used half the wires for + and the other half as -
Ok, so you were using it for power only not data……that makes alot more sense.
 
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tech_junkie

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Ok, so you were using it for power not data……that makes alot more sense.
I also ran the same 22Ga STP CMX cable for data to the remote switch.
Looking at my note from school 20 years ago:
The 100 meter limitation is newer. Because it used to be (for data and POE) 1500 and 500 on 20 ga , 1200 and 350 on 22 ga,, 1100 and 300 on 23 ga and 1000 and 250 for 24 Ga.
I'm guessing frequency spec of the wire and wire alloy is governing the new constraints. But I imagine it depends on what you want to run. Cameras only need 15Mbps bandwidth at the most per camera and in my install 450 ft away it still linked at 1Gb even though it only needed 100M to service the four cameras.
 

tigerwillow1

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The port does that when you plug it in and it first test is to see if pins 4&5 are shorted, then it checks if 3&6 are shorted as well as pins 7&8 to see if its shorted so it would apply power appropriately.
I could probably could dig up the POE controller ic datasheet to show you how that operates on the hardware level..
The device is preset to whatever POE power scheme it uses, and the port it plugs into (switch or router) senses if it is type A or type B
Please post a link to that data sheet. This is crazy how many web sites have it wrong! For instance, wikipedia says in plain language "The PSE, not the PD, decides whether power mode A or B shall be used. PDs that implement only mode A or mode B are disallowed by the standard. " Power over Ethernet - Wikipedia .

And dozens of web sites describe the discovery and negotiation process without ever mentioning the three tests for shorted pins.

Capture.JPG

This is classification, image from Power over Ethernet (PoE) . For discovery it says "PSE leaves the Ethernet port unpowered and periodically checks if something has been plugged in. The low voltage used during detection is unlikely to damage a device not designed for PoE. When a PD is connected to the PSE’s port, the PSE detects this and carries on to the classification stage." Not a peep abut checking for the shorted pairs! And many other sites say the same darn thing.
 

International784

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Mains grounding should never be an issue because of how the Ethernet standard is implemented. However, I did do an installation similar to yours with an additional burial CAT5 wire in the conduit 450 feet that powered the switch because the welding equipment would interfere with the electrical power at the remote shed. The POE switch power pack was also plugged into an isolation transformer and then into an online UPS. That shop building has been hit by lightning several times since I installed that system and it never went down. Even when it was directly struck by lightning.
May I ask what isolation transformer you’re using?
 

tech_junkie

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This is classification, image from Power over Ethernet (PoE) . For discovery it says "PSE leaves the Ethernet port unpowered and periodically checks if something has been plugged in. The low voltage used during detection is unlikely to damage a device not designed for PoE. When a PD is connected to the PSE’s port, the PSE detects this and carries on to the classification stage." Not a peep abut checking for the shorted pairs! And many other sites say the same darn thing.
That is because people can explain the same function in different ways and even different PSE controller IC datasheets will explain the same thing in different ways.
Here is an IC that is used in 8 port POE switches: They explain it as a "current fold back engine"
 
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tigerwillow1

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That's a pretty complete data sheet. The answers for determining whether and how to apply power look to be on pages 21-23 and 132-133. A pretty complex negotiation in some of the cases.
 
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