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Airplane777
join:2004-06-20

1 edit

Airplane777 to slipstream1

Member

to slipstream1

Re: CAT5e CMR/CMX mean it's uv rated ?

Hi slipstream1:

Does the following link show the cable you are using?

»www.superioressex.com/pr ··· -cmx.htm

It is a residential indoor/outdoor cable. It does have uv protection.

The link says the cable is CMX rated, but doesn't define what CMX stands for.

I know CMR has something to do with cable being used in risers in homes...whatever risers are.

So maybe I want a cable that is CMX and CMR rated?

robbin
Mod
join:2000-09-21
Leander, TX

robbin

Mod

said by Airplane777:

...So maybe I want a cable that is CMX and CMR rated?
Great question -- we see it all the time but what does it mean. I found a PDF which shows the difference. The table on page two puts everything into perspective!

WOW -- just found a great site for everything else you may want to know about cable -- read this!
slipstream1
Premium Member
join:2005-11-15
Jacksonville, TX

slipstream1 to Airplane777

Premium Member

to Airplane777
That is the cable that I use. I also use a commscope shielded outdoor cable with a drain wire that I bought from electrocom for the big tower.
Stealthwave
join:2005-07-03
Alvin, TX

Stealthwave

Member

The shielded Cat5e from Defacto also has a drain wire.
jdmarti1
Jack
join:2004-06-15
Oilton, OK

jdmarti1

Member

The gel filled cable we use from shireen is also shielded and has a drain. We use it for all installs - tower, customers, everything. We use some inexpensive blue stuff for PoE to router.
Airplane777
join:2004-06-20

1 edit

Airplane777

Member

Hi jdmarti1:

I called a mfg and from talking to them, they said their outdoor rated cable wasn't suitable for indoors...well it was up to 50 feet indoors. Then after that, the indoor cable has to be rated for indoor use. If I remember correctly, I think that was Superior Essex.

However, I would think, if plenum cable wasn't needed indoors, I don't see why regular outdoor rated cable wouldn't be good enough indoors. However, there is something about the CMR cable needing to be used indoors. It has some kind of flame rating, but it just isn't plenum rated. I have to do more reading in that area.

John Galt6
Forward, March
Premium Member
join:2004-09-30
Happy Camp

John Galt6

Premium Member

said by Airplane777:

However, I would think, if plenum cable wasn't needed indoors, I don't see why regular outdoor rated cable wouldn't be good enough indoors. However, there is something about the CMR cable needing to be used indoors. It has some kind of flame rating, but it just isn't plenum rated. I have to do more reading in that area.
It is all about "flame spread" and "products of combustion"...

Plenum rated cables are rated for use in air-handling spaces. They typically have PTFE (Teflon) jackets and have very low FS and POC values. In addition, the electrical characteristics are usually superior to other cables.

Another point in passing...all of these cables behave differently (from one type and manufacturer to another) in regards to low-temperature handling characteristics. If you are in an area that experiences low temps and you have to install during those times, you may have "difficulties"...primarily jacket fracture.

Something else to worry about...!

Very generally speaking, "name-brand" cables will perform better over a wider variety of circumstances than "no-name" cable.


robbin
Mod
join:2000-09-21
Leander, TX

1 edit

robbin to Airplane777

Mod

to Airplane777
said by Airplane777:

...However, I would think, if plenum cable wasn't needed indoors, I don't see why regular outdoor rated cable wouldn't be good enough indoors. However, there is something about the CMR cable needing to be used indoors. It has some kind of flame rating, but it just isn't plenum rated. I have to do more reading in that area.
Please read the links I posted. The ratings you posted are UL ratings. You need to use UL listed cable for most code purposes (outdoor cables such as the Superior-Essex OSP cable I referred to earlier are not Underwriters Laboratories rated as they terminate at the demarc and therefore have no need for UL approval). UL does not "rate" cables for outdoor as far as I know.

There is really no need to extend your outdoor cable indoors as you should have a surge suppressor at or the close to the point of entry so as long as your indoor cable is properly rated and your outdoor cable ends at your demarc (lightning surge suppressor) everything should be fine.

Having said that, I have to wonder if a CMR-CMX rated cable which has outdoor printed on it can be run for more that 50 feet indoors?
Airplane777
join:2004-06-20

Airplane777

Member

I think the 50 feet she mentioned had something to do with some kind of legal issue of using it indoors. Probably a flame rating.

So it seems like we have to worry about ratings from a couple different organizations for the cables.

John Galt6
Forward, March
Premium Member
join:2004-09-30
Happy Camp

John Galt6 to robbin

Premium Member

to robbin
said by robbin:

There is really no need to extend your outdoor cable indoors as you should have a surge suppressor at or the close to the point of entry so as long as your indoor cable is properly rated and your outdoor cable ends at your demarc (lightning surge suppressor) everything should be fine.

There you have it...!


robbin
Mod
join:2000-09-21
Leander, TX

2 edits

robbin

Mod

Actually, I really like the Belden 1594A cable and normally use it indoors although I try to design my installations so I don't have long interior runs. I do wonder exactly what code is on this. Here is my reasoning -- it doesn't make sense to rate outdoor cable CMR; which is tested to be in compliance with UL-1666 "This is a fire test for determining values of flame propagation height for electrical and optical-fiber cables that are for installation vertically in shafts or in vertical runs that penetrate more than one floor." Why rate the cable for risers if it can only be used for 50 feet indoors. It makes much more sense to me that an outdoor cable (such as Superior-Essex BBDN) can be used up to 50 feet indoors even though it is not rated for indoor use.

I have been using the Superior Essex cable to the surge suppressor and then the Belden 1594A inside the house but I worry about the 50 foot limit. Perhaps there is nothing to be worried about as it is rated CMR-CMX which should allow for unlimited indoor usage? This actually goes with what you said earlier John -- it's nice not to have to carry around too many different cable types. I keep a little plenum cable around but rarely need it. I have never seen an outdoor rated plenum cable.

[edit for spelling]
robbin

robbin to Airplane777

Mod

to Airplane777
said by Airplane777:

...So it seems like we have to worry about ratings from a couple different organizations for the cables.
I believe all of this revolves around the NEC. Code requires UL approved materials and the different ratings simply specify the usages allowed for a given cable. Code also requires that the surge suppressor be rated for it's intended purpose (once again it should have a UL rating).