sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services Cabling Telephones Systems Wiring surge protectors

Recently, I needed the ability to extend our PC network (ethernet) to a building located about 100 feet away. There is parking lot between the buildings with a big 50-pair bundle of phone cable going between the buildings under the parking lot. I found a "hyperextender" kit that allowed me to make the link using a single pair from this bundle. If I understand correctly, the two black boxes in the kit use a DSL type method to talk to each other. This setup worked great for about a month. Last night we had a thunderstorm and while the ethernet ports on the devices still seem to work, the "link" ports that connect the devices using the single pair evidently got fried. The company I got them from is sending out replacement units, but I certainly don't want to have to replace them every time it rains. I have a couple of Lucent 146C tip/ring surge protectors that I'm not using. Can I use these to protect my devices or should I be using something else? I'm assuming I would want to put some kind of protection behind each of the black boxes - between each black box and the run that goes across the parking lot.

"Excerpts from NEC Chapter 800 “Communications Circuits”

"Primary protectors provide protection against overvoltage and overcurrent conditions that occur due to contact between outside communication conductors and power sources outside of the building. Thus, they allow for safe direct connection of internal power limited circuits and equipment to conductors that originate outside of the building.

"A listed primary protector is required for each communications circuit [800.90]. Locate it as close as practicable to the point of entrance [800.90(B)]. Keeping the shortest practicable distance between the primary protector location and the primary protector grounding conductor [800.100(A)(4)] reduces differences in potential between communications circuits and other metallic systems — very important during lightning events."

You need to get a qualified communications electrician to install the mandated protection, as referenced above.

"I, too, gotta get out of this business."

Outdoor 10/100 Base-T CAT5 Lightning Surge Protector with RJ45 Jacks

https://www.hyperlinktech.com/item.aspx?id=947

Sorry, but those are just toys; "feel-good" devices. Any device that relies upon "RJ45" connections cannot possibly provide true inter-building protection. These units are secondary protectors, not primary. Modular jacks cannot convey the high levels of surge current required of a proper cable protection device.

You still need properly-installed building entrance terminal to provide primary protection on the cable. The cable sheath needs to be bonded to each building's electrical service ground. This is obviously not present.

It isn't the lightning that causes most of these problems; it is the difference in ground potential between the buildings when there is lightning activity in the area.

You should check with your local telco and get hold of one of their sub contractors who install underground/aerial cable for them. Everyone that you find in the Yellow Pages will tell you that they know what they are doing, but many don't when it comes to this stuff. Their lack of knowledge won't surface until the next time it rains.

As Arthur stated, hire a professional who understands all aspects of the National Electrical Code (NEC), protection and bonding to do it right. Insist that they provide references for similar projects and verify that the work that was done actually solved the problem. With communications, lightning DOES strike twice in the same place.

tkerschen,
Have you considered a GOOD commercial grade point to point wireless for you data network extension?

We have customers pushing several miles with line of site point to point wireless that is very reliable.

Just a thought................

First is there primary protection? you need to identify that or at least if so let us know. The reason is we are working on speculation here.

If the primary is not in place, do as Bloom and Ed said. After the primary you will need secondary which for all purposes here has to be bonded just like the primary. Then you need to look at the voltage and amps your devices are allowed to accept before blowing and the required voltages needed for the device to work properly.

Your secondary protection has to have a "clamp rate" that is acceptable along with the correct over current rate.

Michael has a very good idea. At 100 feet it would be painless to install a point to point wireless. The paddles are small and not prone to the same storm issues as the in ground cable.

All good points. After you've decided on the primary protection, then if I may add one more option: run a single (properly shielded) outdoor-rated cat5e or higher cable between the buildings. 100ft is well within the standard.
The Lucent protectors you mention are secondary protectors - used within buildings. What you may need is some sort of irob protection.

Sorry I haven't replied. I'm on site now trying to resolve this. The company I got the "network extension" devices from sent out replacements and I'm up and running again. I also asked for recommendations from them on surge protectors and they linked me to a couple of devices which I suppose would qualify as "feel-good" devices as described above. Well, I don't feel real good about it, but if they are willing to recommend it to protect their $430 equipment, I guess I'll give it a try. Thank you.

is there any way to run fiber ?

maybe behind the parking lot , you don't have the distance limitation and and wouldn't have to worry about surge protection

The buidlings have nothing but concrete between them. I think any re-cabling is going to be expensive. Here's a pic of the premises: https://www.swpaper.com/images/swpokcbd.jpg
Tom