Do I need "special" ethernet cable for running through a hot attic?

NeverDie

NeverDie

Senior Member
Very soon, before it gets too hot to work in the attic, I need to run some Ethernet cable between my office (the hub), through the attic, to various rooms in the house that are easily accessible from the attic.  To keep my life easy, I was planning to buy premade Ethernet cable (with the RJ45 connectors already attached) and run with that.  I'll be running shielded Cat7 cable.
 
The attic can get hot during the summer.  I've measured the attic air temp last year, and it never exceeded 115F.  Based on that I think it's very unlikely the attic air temperature would ever exceed 130F.
 
Do I need any kind of "special" Ethernet cabling to run through this attic space, or will any off-the-shelf premade Ethernet cabling do?  Are there any particular standards it should meet?  Not sure if it matters, but local electrical code is the same as the NEC code.
 
I would be using the Ethernet cable purely for data transfer at gigabit speeds, so it's going to be typical low voltage. 
 
I would like to piggy back on that and ask about running along the outside of the home as well. What is required for that sort of thing? Not directly exposed to sunlight but having to deal with winter temps.
 
Here have just regular plenum grade cat5e in the attics here in the midwest and Florida.  Its been 10 years in the midwest.  I am using said cable for network and serial stuff.  This is how I get to wiring up the 2nd floor here.  I initially built a cat walk in the attic and added some lighting (well its daylight with all of the lights on).  The ceilings / top is over 8 feet.  I have used a ladder to work up there.  I did recently added more cabling for the LCD TV mounted in my home office.  Kind of a pita as it starts in the basement comm area; goes up a chase to the attic then down to the office.  Just ends in a patch panel in the basement and mostly using wall plates and Keystone jacks.  Its more difficult to pull cable with RJ-45 ends on it as the little RJ-45 end clip can be broken easily and or the wires pulled out of the jack.  (I would put a piece tape around the end maybe).
 
A couple of years ago helped a friend run outdoor cat6 between two houses (on a farm) for network connectivity.  The run is just around 300 feet and has been working fine for a couple of years.  He rented a trencher for a day.  The wire is not in conduit and probably a bit over a foot underground.
 
By the way, my attic is not a plenum in any normal sense of that word.  That said, the HVAC gear is there, and I can't be sure the flex duct that's run between it and all the rooms of the house is 100.0000% perfectly air sealed at every connecting point.
 
Also, I don't know that "riser" is really an applicable term either.  Granted, the Ethernet cable will "rise" from patch panels on the wall (at typical electrical outlet height) up through the top plate (with drywall on either side, because these are typical walls) and into the attic, but I would think it's a bit of stretch to call that a riser.  Or is it?
 
Once in the attic, it won't be confined to a chase of any kind.
 
Also, for this application, is  solid core better than stranded?
 
Yeah; just had a box of it around so I used it.  I didn't really buy it for my stuff though; just left over stuff; such that it was cheap (well free).
 
It's not in any kind of chase in the attic.  I did sort of create little d-marks over each room sort of centered and down.  More for me to tell where the centers of the 2nd floor rooms are.  Thinking about it; its sort of a multiple attic set up.  IE: some ceilings are vaulted and there is skylights in the mix which get a bit in the way. (big boxes which are insulated in the attic from the top to the bottom). 
 
Most difficult "do what" in the attic was the DIY installation of a chandelier lift.  Its a bit bigger than a garage door opener and I had to change the support structure a bit, run a new circuit to it and connect up the LV switch (well its just a key switch).  Its sort of a cable and a winch and very slow to move.
 
Think it supports up to 600 lbs. 
 
Maybe this will do?  
 
http://www.amazon.com/Certified-Blue-Cable-Assembled-Jeans/dp/B00IITTID0/ref=sr_1_5?s=pc&ie=UTF8&qid=1399398561&sr=1-5&keywords=cmr+50
 
It's CMR rated.  Also, it claims it can support 10 gigabit speeds.  It also says it comes with a test report certification (?) that it meets the full Cat6a spec.
 
I guess I could just buy bulk cat6a wire that's CMR rated, but I've never put the RJ45's on before with the crimp tool, and it would be a shame to buy the nice cable and then have impairment at the connection point just because I fat fingered the RJ45 crimps (or however it's done for cat6a).  Are the crimping tools for 10gig idiot proof these days?

 
 
but I've never put the RJ45's on before with the crimp tool
Click to expand...
 
For the Keystone jacks / patch panel its just a punch tool and color coding matching.  You can buy some short patch cables or make them up.  Typically the Keystone jacks come with a little plastic punch tool.  Its sort of difficult to use as its only about 1-2". After testing the end; if it doesn't work just cut it off and put a new one on.  My isssues have historically been relating to making the ends even.  If they are not even and pushed all of the way into the RJ-45 then the crimping will be crimping air and not wire.  But really you can buy patch cables for very little this days; any size and any color. I have "issues" with the little hoods over the end for tight connections.  (IE like firewall with multiple NIC cards in it; makes for a very tight fit).
 
I like those new keystone wall plates which you can fit multiple jacks on.  The one for the LCD TV in the office is one plate with HDMI, Network, Audio on it; small footprint and it looks nice with short cables to the LCD TV.  It does look better than just a cable with an RJ-45 coming out the wall.  You can also purchase keystone jacks that have RJ-45 ends on both side for using made up RJ-45 cables. I did purchase that thin RG-6; a bit more expensive but works well with the OTA stuff.
 
The second floor networking is all Gb today.  Only real need for the Gb is in the transfers of large Gb files.  Streaming HD video works just fine (even at 100Mb).
 
I would utilize one of those compression type of RJ-45 devices and purchase a cable tester.  The last one purchased (well el cheapo one) does work well telling me the pairs, length, so forth and so on.  The little testers with the LEDs just tell you that your pairs match but not which pairs are what.
 
In terms of expected performance, would using a tested patch cable such as the one on Amazon above be better than using bulk cable and keystone jacks, or would the keystone jacks give equivalent performance?

Time Warner is upgrading me (for free) to 300mbps internet by or before this Fall. Or, so they claim. That's because gigabit internet isn't far behind and is already getting rolled out around town (thanks to Google's Gigabit Internet service ramping up here).

Add some file server access over the same pathway and suddenly, gigabit ethernet doesn't sound fast enough anymore. The cable isn't very costly compared to the internet service, and so I figure something that can support 10gbps should last a while, and so (somewhat arbitrarily) that's what I'm aiming for.
 
In terms of expected performance, would using a tested patch cable such as the one on Amazon above be better than using bulk cable and keystone jacks, or would the keystone jacks give equivalent performance?
Click to expand...
 
Personally yes.  There is a slight chance that a "tested patch cable" could be bad and that would have you cutting the ends off anyways.  Mostly in a commercial environment a keystone jack or similar is utilized.  Way back in the 90's do recall doing new banks and having the cabling company certify each of their cables on a spreadsheet.  We would even look at the patch panel to make sure that the ends were cut just right/flush or even cut. Typically the certs spreadsheet was all that was needed.
 
pete_c said:
You can also purchase keystone jacks that have RJ-45 ends on both side for using made up RJ-45 cables. 
Click to expand...
 
Well, that makes it easy.  No skill required.  I was hoping it existed, and now you've confirmed it.  That's my ticket for this project.
 
Thanks!
 
Thinking Monoprice also has this stuff and delivery is quick as it's a domestic delivery. 
 
I recently went to color coded RJ-45 Keystone jacks.  I do label the wires at the patch panel and in the wall where it goes to the keystone jack.
 
I know now what I am using them for but will probably forget should I remove the patch cable. (in the office I have one keystone wall plate with 6 keystone jacks on it;   1 is a POE jack that is labeled sort of.
 
in our remodel I ran about 8K feet of cat6 and terminated the ends using EzJacks / plugs. These work pretty well, and once you're in the thick of things not too awkward.


these type of connectors work by stripping the shielding to expose the internal wires, sequencing these and sliding them through the connector. The wires stick out the other end... and you don't run into 'getting the ends even' problems.


I did have failures - probably about 5 connector failures out of a 50 or so.


this giant octopus of wire was then mostly punched down into a stack of patchbays.


the cable is color coded, btw. the keystone jacks too. Monoprice supplied the cabling and the switches. the patchbays were from Amazon.


to get back to your core question you won't need any special special cable for a hot room.
 
BaduFamily said:
to get back to your core question you won't need any special special cable for a hot room.
Click to expand...
 
One of the possible topics we didn't hit on was whether there's a performance drop in for cabling that runs through hot spaces. Not sure if it's a relevant comparison, but maybe there's some analogy with how the ampacity of line voltage romex decreases as the ambient temperature increases, and the various NEC rules for calculating the derated value.
 
Because I needed to knock out the above project soon before it gets much hotter, I did pull the trigger on ordering the CMR rated 50 foot Cat6A ethernet patch cable that I linked to above, so in that sense it's moot.  If it turns out that cable is overkill, at least it's overkill that will arrive two days from today.   :)   
 
In any event, in part it was concern about possible heat related derating that led me to  target cable rated for sustained 10Gbps speeds.  I'm sure there will be future occasions, and so I'd be interested in knowing for future reference.  
 
I wouldn't go through the effort to buy preterminated cables...especially patch cables. It's an effort in futility because you're going to inevitably knock the tabs off the plugs or damage an end running them through bored holes. Putting an end on tinsel wire is not fun.
 
Buy yourself a 1M box or 2 of cable and a bunch of ends and be done with it.
 
The ambient for an attic and cabling is not significant. Romex and other NM cabling is not derated for an attic 99% of the time in a residential. The NEC does not derate LV based on temperature at all. We're not talking big extremes here, like a steel mill.....you're looking at an attic.
 
Cabling run outside should be, at minimum, sunlight resistant jacket and rated for wet conditions, which typically means gel filled or direct burial rated.
 
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