sundance-communications.com/forum Forums TDM Business Telephone Systems NEC Telephones & Systems NEC.... Copper to Fiber

Hello all,

I am new to the club, and have no knowledge about phone systems. I've done plenty of data comm stuff (Cat5, Fiber, WiFi), but no phone systems.

My company is splitting up some of our personel and putting them in a building about 500' from our current office. Our telphone man told us just to run a 25 pair cable from our phone system to the other building and punch it down on a 25 Pair Demarc block, then connect all our stations to that block.

We would rather run a fiber cable to connect the two building, that way we can push all our data and voice over it, and not have to worry with lightning protecion, and all the other electrical worries that come with long copper runs. However, our phone man has only done this type of connection one other time in the past, he said it was so bad, that they put it back on copper.

I would assume that all you need is some sort of media converter on both ends. Do you guys know what devices I need, and where I can get them?

We have an NEC DX7NA-48 phone system.

Thanks!

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kbldawg

There are no fiber media convertors for any phone system.

All manufacturers use proprietary signalling for their equipment.

As you stated above, running a 25 pair feeder cable is the best way to do this.

Just make sure that who ever installs this uses underground feeder cable (even if it is going in conduit) and that they install Primary protection on both ends per National Electric Code and bond the underground cable only on one end.

I would also recomend installing secondary surge protection as the primary protection is usually not fast enough for the circuitry in the phone system.


DJ

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Watson to Bell: "It must be working, all I get is a busy signal"

For sure use copper
and be sure it is underground rated gell filled

questions: Call SBC repair 214.455.7735

Jules

I appreciate your input. What type of surge protection should I use (on both ends of the feeder) and where can I get it? Any suggestions on that?

Thanks So Much!!!

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kbldawg

Don't skimp on your primary protectors. To buy one fully equipped can cost up to $500.00 each. Get something made by a outside plant equipment manufacturer, like:

Emerson Network Power (formerly Marconi; formerly Reliable) BEPC-25 series

Corning (formerly Siecor);

Circa Manufacturing;

Tii Industries;

Most supply houses, like Sprint North Supply or Graybar Electric stock these. You will likely want to get one that has a 66 block input and output.

Don't buy the simple blocks that have plug-in modules. They aren't rated, although they say they are, for true outside plant exposure. I have seen them literally blown off the wall.

For secondary protection, we have had good luck with Panamax 25 pair protectors. They connect with a simple plug-in arrangement.

Don't forget that when you purchase your primary protectors, they DO NOT usually come with plug-in protector modules. These are sold separately through the same supplier. If your finances will permit, splurge on the higher-quality solid state modules.

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Ed
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How come there's always enough time to go back and fix it a second time?

Thanks everyone for the excellent information!! I think I'm ready to tackle this project, hopefully with great success.

We deal with our local Graybar exclusively for all our data comm stuff, so there should be no problem finding the stuff we need.

Select your lightning protection carefully as you shouldn't need to buy one module to protect ten circuits. If one circuit takes a hit and the module blows you have to replace the protection for all ten. There are good systems out there that allow you to protect individual circuits and the cost saving following a hit can be considerable.