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garys_2k
Premium
join:2004-05-07
Farmington, MI
Reviews:
·Callcentric

RG6 Cable Rating Req'd for New House Construction?

I'm pre-wiring my new house for cable and Ethernet and need to ask the pro's a question: Can you run CM rated cable (enclosed in a wall cavity) between a wood-frame house's basement and first floor, or do you need to use CR cable where it runs between floors? It was easy to find CR rated Ethernet cable, and that's what I bought, but CR rated RG6 is proving more difficult to find.

None of these runs will be anywhere near air-carrying chases, so I don't need plenum rated cable. It's just the runs between basement and first floor that are the concern. I know that CM is fine in wall cavities within a single floor, too.


OldCableGuy

@communications.net
I have no idea if it is CM or CR (never heard of those) but I've installed probably 1000 miles of regular coax RG6 and RG6 quad shield cable in homes over the years within wall cavities and between floors, all of which have been inspected and signed off on during the construction process by home inspectors.

I usually opt for quad shield if the client is willing to pay a few dollars more because it is in spec for minidish, also where I live ImOn requires quad shield for all lines. That is really the only concern I have is making sure you get quad sheid swept to 2ghz.

robbin
Premium,MVM
join:2000-09-21
Leander, TX
kudos:1
reply to garys_2k
My understanding is that CM is ok in single family and duplex. CMR would be needed if it was a commercial structure.

TheMG
Premium
join:2007-09-04
Canada
kudos:3
Reviews:
·NorthWest Tel
reply to OldCableGuy
said by OldCableGuy :

making sure you get quad sheid swept to 2ghz.

What exactly do they mean when they say this?

I'm wondering because I've only ever heard this when speaking of CATV and satellite TV.

I deal a lot with RF systems and coaxial cables at work (but not CATV), and have never seen a manufacturer's datasheet mention "swept to xGHz".

What they do is they include a table or graph of dB loss per unit length vs frequency.

How high a frequency a particular cable will be suitable for, greatly depends on the installed length, and the strength of the input signal vs the minimum acceptable signal level at the other end.

Saying "swept to 2GHz" doesn't really say anything about the cable's specifications or performance.


Killa200
Premium
join:2005-12-02
Southeast TN
Reviews:
·Charter
reply to garys_2k
My the book it is CM for in wall, CMR for in wall same where the cable will go between floors of a building, and CMP for anything ran in an air space.

You may have better luck with video cables looking for a CL2 or CL3 rated cable. CL2, CL2X, CL3, and CL3X are riser rated for single family units. CL2R, CL3R, CL2P, and CL3P are riser rated for any building, whether it be single family, multi dwelling, or commercial.


Killa200
Premium
join:2005-12-02
Southeast TN
Reviews:
·Charter
reply to TheMG
said by TheMG:

said by OldCableGuy :

making sure you get quad sheid swept to 2ghz.

What exactly do they mean when they say this?

They guarantee cable to operate at or better than what they sweep it to in cable like this. After the "swept to" value, they don't guarantee its ability to maintain the same roll off pattern as what is listed in the sweep chart.


Wireman

@173.209.204.x
reply to garys_2k
According to 725.154(E)(4), type CL2X and CL3X in cable sizes 6mm (0.25in) in diameter are permitted. Table 725.154(G) lists both CM and CMR as acceptable substitutes for type CL2X. The short answer is CM or CMR is okay for your purpose. You'll need to use an approved fire stop sealant at the penetrations between floors.


54067323

join:2012-09-25
Tuscaloosa, AL
reply to garys_2k
said by garys_2k:

Can you run CM rated cable (enclosed in a wall cavity) between a wood-frame house's basement and first floor, or do you need to use CR cable where it runs between floors?

In a single family home you can use CM for that application.


Kramer
Premium,Mod
join:2000-08-03
Richmond, VA
kudos:2

2 edits
reply to garys_2k
Not related to your CM question but something you may or may not already know about RG6 ...

One thing I learned about RG6 unfortunately after I had purchased and run the cable is that there are other concerns besides the quality of the shielding. Most of the cable you find sold is copper clad. That means there is a steel core. If you put a magnet on the core it will stick. It is simply copper clad. Supposedly electrons move mostly around a surface. One or more of the satellite companies require or at least recommend a solid copper core. That cable is much more expensive, probably by a factor of at least 50%. I wish I had used it although I have had absolutely no problems at all with FIOS. I may switch to satellite at some point and I hope the cable I used isn't a problem. I would hate to have to do that over again.

Wireman Can you give an example (product) of an approved sealant for use between floors. Thanks

garys_2k
Premium
join:2004-05-07
Farmington, MI
Reviews:
·Callcentric
reply to garys_2k
I just called my city inspector and he said that nobody's ever asked that question before, they never look for CR rated cable in a single family house and that the only gotcha to watch out for is to make sure I use firestop between floors (already bought it).

So, I guess the CM stuff (also listed as CL2, but I think that's more about the voltage levels it will withstand) will be fine. As for solid copper, that MAY be something I'll work on but none of the runs will be very long. I'll likely go with the CCS.

medbuyer

join:2003-11-20
kudos:4
reply to garys_2k
I would get or use a solid copper core rg6 and not copper clad...something like this...»www.solidsignal.com/pview.asp?p=···6scdlqd)

I did a re-wire on my satellite using that cable and so far so good.

for ethernet, I would run cat6 at least.

Use 2 runs of each on each location and then terminating them to a location where all cables meet just like how a structured media would look like.


davidg
Good Bye My Friend
Premium,MVM
join:2002-06-15
none
reply to TheMG
said by TheMG:

I deal a lot with RF systems and coaxial cables at work (but not CATV), and have never seen a manufacturer's datasheet mention "swept to xGHz".

What they do is they include a table or graph of dB loss per unit length vs frequency.

How high a frequency a particular cable will be suitable for, greatly depends on the installed length, and the strength of the input signal vs the minimum acceptable signal level at the other end.

Saying "swept to 2GHz" doesn't really say anything about the cable's specifications or performance.

then you have never dealt with cable for cellular either. You pay more for the same cable because the factory sweeps it to make sure it passes spec up to a certain frequency. In MOST cases the cable will work fine for any frequency so long as it is sized for loss, which is the other part of your post. The sweep is just to certify the cable will work up to a certain frequency for all portions along it length. a minor kink or imperfection in a cable that is harmless at VHF will kill a 1.9g signal. Heck, failure to properly clean the end of the cable before installing a connector will give you fits too. This is the reason why more and more radio shops are backing off using a wattmeter on system cables and instead sweeping with an anritsu.

So yeah, sweeping it says the cable meets the specs thruout. If you pay for swept cable and it has a flaw that affects only certain freqs you can get it replaced easier. If you got unswept cable that works fine in most instances but not your particular frequency, then you are stuck dealing with it.
--
Lack of Preparation on YOUR Part does NOT Constitute an Emergency on Mine!


nunya
LXI 483
Premium,MVM
join:2000-12-23
O Fallon, MO
kudos:12
Reviews:
·Charter
·voip.ms
reply to garys_2k
I've run a few thousand miles of cable myself. I do know what CM, CMX, CMG, CMR, and CMP means.
In a single family dwelling, you can use plain old CM or CMX (CATV or CATVX). The NEC does a PISS POOR job of clarifying the cable ratings and requirements. 2011 made it even worse.
Just make sure to firestop your sole plate and top plate penetrations with a good intumescent caulk (just like power).

If it were MY house, I would use riser cable on anything that passes the top plate.

I wouldn't get carried away buying "top of the line" cable either. A copper clad center conductor is nothing to be ashamed of (see skin effect). Tri-shield is usually sufficient. Quad-shield is the best.
--
If someone refers to herself / himself as a "guru", they probably aren't.


54067323

join:2012-09-25
Tuscaloosa, AL
said by nunya:

A copper clad center conductor is nothing to be ashamed of (see skin effect).

A copper clad center conductor is actually easier to use with F connectors.

medbuyer

join:2003-11-20
kudos:4
said by 54067323:

said by nunya:

A copper clad center conductor is nothing to be ashamed of (see skin effect).

A copper clad center conductor is actually easier to use with F connectors.

what? I've crimped both copper clad and solid copper core and can't tell the difference...

unless you're not using the right tool or don't know what you're doing.


PSWired

join:2006-03-26
Annapolis, MD
He's probably talking about the softer solid copper bending over when connecting the F connector and missing the hole.


SparkChaser
Premium
join:2000-06-06
Downingtown, PA
kudos:4
Reviews:
·Verizon FiOS

1 recommendation

said by PSWired:

He's probably talking about the softer solid copper bending over when connecting the F connector and missing the hole.

You're saying he can't get it in the hole?

Hmmm!
--
"Facts do not cease to exist because they are ignored." - Aldous Huxley

"The good thing about science is that it's true whether or not you believe in it." - Neil deGrasse Tyson


OldCableGuy

@communications.net
reply to medbuyer
Unless your soldering copper clad versus solid copper won't make a lick of difference, and no one should ever be soldering an F connector on. Get a SNS crimper and a bag of SNS fittings. I've probably put 10,000 fittings on over the years as a cable installer and the next 10 doing custom installs in homes, never once had an issue.

Liberty

join:2005-06-12
Tucson, AZ
Reviews:
·Cox HSI
reply to garys_2k
I buy my coax by the pallet

I can guarantee you that Dish & DirecTv specifications require 3 gig swept & solid copper conductor only coax
Same with the satellite internet providers, where it is even more critical

As satellite hardware technology moves forward it is sending more voltage out to the dish which is what makes the solid copper stinger necessary
Also the frequency range is expanding as time goes on making 3 gig swept coax beneficial for current generation satellite Tv and necessary for satellite internet
Exede satellite internet is sending upwards of 36 volts out to dish and that plated steel conductor can't handle it

Spend the very few extra $$ now for the better 3gig/solid copper
Hardest part will be finding a source
My sources only sell to businesses that have established an account with them


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom

1 edit

As satellite hardware technology moves forward it is sending more voltage out to the dish which is what makes the solid copper stinger necessary

My Directv dish is hooked up with a 100 ft run of the mill RG-6 from Lowes to the SWM block and I'm sure it's the copper clad type. From there it's on god knows what that was installed years ago for my Primestar service. Probably a 150 ft run total from the dish to the furthest receiver. Never a issue with signal strength or any other adverse conditions. Works just fine on 1080P movies. Now what else on the Directv service could make buying this expensive cable a critical necessity?

Same with the satellite internet providers, where it is even more critical

Used to have Hughesnet satellite. Same set up. No issues.

Exede satellite internet is sending upwards of 36 volts out to dish and that plated steel conductor can't handle it

What is the allowable voltage drop based on the distance and current before performance is degraded?

After my Bose sound system was destroyed in 2003 by Hurricane Isabel I purchased a new system from Best Buy and had the Geek Squad install it. The tech laughed at the "Monster" HDMI cables they had sold me telling me how great they were. He said they were overpriced junk that people have been brainwashed that more cost equals better performance. He said take them back and get my money back and used generic cables which have worked just fine.

Liberty

join:2005-06-12
Tucson, AZ
You are right about your tv working just fine
A Ferrari can run on regular grade gasoline and average guy wouldn't know difference

As far as sat internet - look forward not backward
Todays Ka birds are a new animal...


Jack_in_VA
Premium
join:2007-11-26
North, VA
kudos:1
Reviews:
·Millenicom
said by Liberty:

You are right about your tv working just fine
A Ferrari can run on regular grade gasoline and average guy wouldn't know difference

Perhaps but perception probably plays a larger part than actual performance. Kind of like the old argument about regular, middle and premium gas.

robbin
Premium,MVM
join:2000-09-21
Leander, TX
kudos:1
said by Jack_in_VA:

Kind of like the old argument about regular, middle and premium gas.

Much easier to buy different gas next time than it is to replace in the wall wiring.


54067323

join:2012-09-25
Tuscaloosa, AL
reply to medbuyer
said by medbuyer:

Unless you're not using the right tool or don't know what you're doing.

I thank you for that compliment, however experience by those who actually work with this type of coax have demonstrated the copper plated steel conductor holds up much better in the real world, where end users fail to understand how easy it is to bend a copper center conductor versus a copper plated steel pin of an F connector that goes right into the jack.

None the less, unless one has a major run of coax from a STB to a LNB there is NO reason to run a coax with a copper center conductor.


54067323

join:2012-09-25
Tuscaloosa, AL
reply to Liberty
said by Liberty:

Exede satellite internet is sending upwards of 36 volts out to dish and that plated steel conductor can't handle it

Bullshit.


OldCableGuy

@communications.net
reply to 54067323
You never said that solid copper has problems with stinger failure (it does) you said it's harder to crimp. Are you changing the story now, or did you misspeak before??


54067323

join:2012-09-25
Tuscaloosa, AL
said by OldCableGuy :

said it's harder to crimp. Are you changing the story now

Please point where I stated that, or put a lid on it.

Liberty

join:2005-06-12
Tucson, AZ
Reviews:
·Cox HSI
reply to 54067323
said by 54067323:

said by Liberty:

Exede satellite internet is sending upwards of 36 volts out to dish and that plated steel conductor can't handle it

Bullshit.

Durn, you are right
Seems I remembered wrong
30v-55v
»www.viasat.com/files/assets/Exed···_web.pdf

TheMG
Premium
join:2007-09-04
Canada
kudos:3
Reviews:
·NorthWest Tel
reply to davidg
said by davidg:

then you have never dealt with cable for cellular either.

Indeed I haven't. Nothing much above 1GHz, for the most part only VHF and lower.

said by davidg:

So yeah, sweeping it says the cable meets the specs thruout. If you pay for swept cable and it has a flaw that affects only certain freqs you can get it replaced easier. If you got unswept cable that works fine in most instances but not your particular frequency, then you are stuck dealing with it.

So essentially they sweep each spool of cable that comes off the production line to ensure it meets spec and there are no minor defects that only affect certain frequencies.

Now it all makes sense.

medbuyer

join:2003-11-20
kudos:4
reply to 54067323
said by OldCableGuy :

Unless your soldering copper clad versus solid copper won't make a lick of difference, and no one should ever be soldering an F connector on. Get a SNS crimper and a bag of SNS fittings. I've probably put 10,000 fittings on over the years as a cable installer and the next 10 doing custom installs in homes, never once had an issue.

Did I say I solder RG?

I used this F connector

»www.solidsignal.com/pview.asp?p=···gle_base

with this crimper
»www.solidsignal.com/pview.asp?mc···pression Tools&sku=

said by 54067323:

said by medbuyer:

Unless you're not using the right tool or don't know what you're doing.

I thank you for that compliment, however experience by those who actually work with this type of coax have demonstrated the copper plated steel conductor holds up much better in the real world, where end users fail to understand how easy it is to bend a copper center conductor versus a copper plated steel pin of an F connector that goes right into the jack.

None the less, unless one has a major run of coax from a STB to a LNB there is NO reason to run a coax with a copper center conductor.

You're the first one I've heard of preaching that copper clad holds up much better.

bending or ease of use is just one SMALL factor for choosing the right RG6, the BIGGEST factor is conductivity which plays a big factor also on how much bandwidth it can carry.

certainly steel wrapped in copper is NO BETTER than solid copper.

and yes, my 3 LNB satellite that I used to have with Directv is wired with solid copper all the way to the STB.