atcomsystems.ca/forum Forums Wiring - Telecom Carriers - Trunks & Services Outside Plant OSP Construction Grounding/Protection AGAIN

I read the other posts on grounding but I have some questions. I have been asked to connect two buildings via a 25 pr aerial cable.
I figured that the right way was to install the primary protectors outside and include secondary protectors inside at the KSU. Digital phones on other end. I assumed (I know!) that primary gas tube terminals with binding posts ( I was told punch-downs arent good for outside) would be easy to find (with weather proof housing) Emerson Network Power makes them but no one has them. With SO MANY of the terminals NOT meant for outdoors installation- And I see alot of primary protection indoors- is there a rule regarding this? How far can I go in before I need the protection? I obviously havnt read the NEC and Im hoping someone who has can help me out. I did find some outdoor terminals that were very expensive and Im hoping to not have to spend $600 per building as mentioned on an earlier post.
Ive been reading up on grounding for amateur radio stations and alot of it applies to telecom as well. I realize just how poorly done most installations really are! I already have learned one lesson regarding pricing for lightning protection. I assumed that if a 25 pr indoor terminal with modules costs $200 then an outdoor one would be similar. I was wrong. So now Im trying to do a safe installation at minimum cost. Or will I just have to learn this lesson the hard way? Thanks!
PS the aerial cable is only 20 feet and my equipment is another 20 feet inside.

800-30 of the NEC covers protection between buildings. I've see it interpreted several ways. Bottom line is if the conditions warrant protect it.

Since our industry has become "lowest price", a lot of suppliers have stopped stocking true outside plant protectors. Most of what my company buys these days is on e-bay. If you enter "building entrance terminal" or "protected entrance terminal" in e-bay's search, there are some very reasonably-priced posts. If you have a credit card, you can pick up what you are looking for cheeeeeeep prices. Even though most of the listings have 3M MS2 module inputs, you can always cut the module off and splice the input cable pair-for-pair using Scotchloks or some other single-conductor means. If you do this, do it one conductor at a time because their input wires are not band-marked, they are striped and it's hard to differentiate between tip and ring.

Just remember that these terminals are empty, meaning that they don't include the plug-in protector modules. You will need to buy them separately. All of the terminals that I have seen lately on e-bay are only rated for indoor installations.

You can legally enter a building "unprotected" for up to 50 feet; beyond that, the cable must be enclosed in metallic conduit. You also have to deal with plenum ceiling issues, since OSP cable can't be run in that environment under any circumsances. It burns like a match!

Cheapie secondary punch-down protectors are appropriate for supplemental protection as you mentioned, but they can't be trusted as a means to terminate an outside-plant cable. Good call on your part for asking for a second opinion!

Ed, Thanks for the advice. The 50' limit was important to my situation. Can an indoor terminal be mounted in a weather proof box or are the modules not suitable for the temperature extremes? In my situation I have only enough OSP cable to terminate outdoors ( I have run a 25 pr indoor rated from the outside to the inside) I planned on terminating them both in the outside protector. Im thinking now that I should just splice the two together in a weather tight box on the building(s) and use indoor primary protection. How does that sound? Plenum isnt an issue. However the PVC 25 pr does run through an unheated crawl space. Thanks again!

Well, a decent weatherproof enclosure will be fine and I don't think temperatures will be an issue. Just one thing, though: Don't use a simple electrical junction box. It's possible that condensation can collect inside and cause problems. Use an enclosure designed for telecommunications equipment that has screened ventilation holes.

Usually in cases like this, we use an inexpensive splice pedestal with a divider plate to mount the protector itself. Even with aerial cable, we just come down the wall of the building and up into the pedestal. Every installation has it's own set of circumstances, so this may not be appropriate for you.

Emerson Network Power (formerly Reliable/Reltec and Marconi) make some nice green enclosures with a plywood backboard. They come in three sizes to accommodate just about any equipment configuration. The part numbers are:

BUPNP1 (F019647) 14.75" X 16"
BUPNP2 (F019648) 24.25" X 16"
BUPNP3 (F019649) 30" X 19.5"

These are a bit on the expensive end (over $100.00), but they are exactly what you need to do it correctly.