Reply With QuoteTo clear up this problem you will need to buy two new surge protectors as the ones you have now have done their job to the point of failure. Should you decide not to then the computer will be the protector next time
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grounding outdoor ethernet cables
I have a shielded, outdoor ethernet cable running between two rural buildings. The Cat5 cable is shielded with a metallic sheath and has a drain line running through it to both ends for grounding purposes. I bought two L-Comm weatherproof lightning surge protectors and installed one at each end of the 250' cable. There are two shorter Cat5 cables connected to the lightning protectors which go on into each building. There are also grounding wires going from each lightning surge protector to a grounding rod located at each building. The system worked fine for about six months, then became erratic, and finally stopped working. After testing to see where the signal was interrupted, I came to the conclusion that the cable was defective and replaced it with a new one which, frustratingly, did not work either. After a lot more testing, I finally isolated the problem somewhat more specifically. If I disconnect the grounding wires from both lightning protectors, the signal goes right through from a router in one building to a computer in the other building. If I reconnect either one of the grounding wires the line is dead at the far end. I got conflicting advice about whether to ground both protectors (the issue being ground loops), but the company told me to ground both of them as they were 250' apart. Technical support at L-Comm has no idea what the problem is and advised me that they may have been damaged by lightning and to buy new ones (at about $70.00 each). I'm reluctant to do this when the signal runs through the lightning protectors just fine without the ground wires being connected to them. It seems to me that there might be a simple solution that no one has thought of. Any suggestions to this grounding problem would be appreciated
To clear up this problem you will need to buy two new surge protectors as the ones you have now have done their job to the point of failure. Should you decide not to then the computer will be the protector next time
+1Originally Posted by jwelectric
Are the ground rods bonded to the building ground? Ethernet over CAT5 cable between buildings with possible ground potential differences can be fraught with issues. I say, rip it out and go with fiber optic cable instead. I do a lot of outdoor CAT5 stuff for APs and cameras, but not so much between buildings. Between buildings I run fiber.
The Drain in the wire is for Shielding, Not Grounding and should not be connected to Ground.
But the Protectors need to be connected to ground, before they will protect properly.
Chances are only 1 of the protectors is bad, remove them completely to determine the bad one.
Don't pay someone to do a job fast, when you can do a half-fast job yourself.
Fiber would be nice, but the transceivers can get a bit pricey.
Wireless may be a cheaper option.
Don't pay someone to do a job fast, when you can do a half-fast job yourself.
The shielding is the ground Don
Their is no connection on a RJ45 (8P8C) for a Ground. The drain is for shielding, Not grounding.
For Your reading Pleasure;
http://en.wikipedia.org/wiki/Modular_connector
http://en.wikipedia.org/wiki/Ethernet_over_twisted_pair
Don't pay someone to do a job fast, when you can do a half-fast job yourself.
also for your reading pleasure
800.100 Cable and Primary Protector Bonding and Grounding.
The primary protector and the metallic member(s) of the cable sheath shall be bonded or grounded as specified in 800.100(A) through (D).
So how do you suggest the Shield in a cat5 cable to be connected ?
Teach us something, Please.
Last edited by DonL; 01-17-2012 at 07:58 AM.
Don't pay someone to do a job fast, when you can do a half-fast job yourself.
I am not an IT person so I leave that in your hands. But I know that it has to have an earth connection and without one the equipment will suffer the total of a lightning strike
I agree that It is very important that the Protector has a earth connection to a ground rod, But Cat5 normally has no shield in the first place.
Using Shielded Cat5 is a waste of money, unless it is running parallel with other Interfering conductors. That is what the twisted pair is for.
Normally the shield just ends at the jack, Because there is no place to connect it. If you do connect it to Ground on Both ends you could get a TRUE Ground Loop big time.
Been there seen that.
Don't pay someone to do a job fast, when you can do a half-fast job yourself.
Yavol, yavol!
I am definitely not a pro plumber, but I am a pro crastinator
I use variety of protectors from DataLinx, Ditek, and L-Com to name a few. Some protectors ground the shield and some don't. Some are designed specifically to allow for POE voltages. The AL-CAT5VW I use has no shield ground while the BT-CAT5-P1J does but it is not really considered entrance protection since it injects POE power..
The shield ground can cause problems with ground loops so in some cases, we isolate the far end, not the entrance. As per code, the entrance must be grounded.
Rather than use STP, I generally will use UTP that is sheathed in armor. My favorite is rodent resist direct burial that has a tough metallic sheath that rodents have a hard time to chew through.
The drain wire on STP connects to the metal hood of the RJ45 plug and some RJ45 jacks do accommodate it with an electrical connection, so I really don't know what you mean by "normally".
Here is a link for UBNT ToughCable:
http://www.ubnt.com/toughcable
Last edited by LLigetfa; 01-17-2012 at 09:28 AM. Reason: added link
Even with the power over Ethernet the Negative Conductor does not go to ground. (Or very rarely, No standard Yet)
If you do connect the shield then it is best to do it at the Router. (Place of signal origin)
There is little code that covers Low Voltage , Low current Connections.
Don't pay someone to do a job fast, when you can do a half-fast job yourself.
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