Cat 5 and PVC

Status
Not open for further replies.
While many might fit i would keep that number low and pipe large.They are easily damaged by tention in pulling.I would not go more than 2 in 3/4

As to other cables it is never a good idea as induction can happen.
 
For your Cat5, the TIA-EIA 568 and 569 requirements are much more strict than the NEC. Here's a couple to see if they help:

568: 4.4.2.4 ?Any single run, extending from a telecommunications closet shall serve no more than three outlets.? (an outlet can be a single jack on a plate. even if you ran 4", you can only have 3 cables in it)
568: 4.4.2.6.3 ?Boxes shall be placed in a straight section of conduit and not used in lieu of a bend.? (no angle or U pull boxes)
569: 4.4.2.1 ?No section of conduit shall be longer than 30m (100ft) or contain more than two 90 degree bends between pull points or pull boxes."
569: 4.4.2.2 ?The inside radius of a bend in a conduit shall be at least 6 times the internal diameter. When the conduit size is greater than 50mm (2 inches), the inside radius shall be at least 10 times the internal diameter of the conduit. For fiber optic cable, the inside radius of a bend shall always be at least 10 times the internal diameter of the conduit?
 
And if you don't care about those standards, the cross sectional area of a cat5e cable is generally accepted to be .045". That's about 17 per 3/4" pipe according to NEC rules. You're nuts if you pull that many.
 
mdshunk said:
568: 4.4.2.6.3 ?Boxes shall be placed in a straight section of conduit and not used in lieu of a bend.? (no angle or U pull boxes)
569: 4.4.2.1 ?No section of conduit shall be longer than 30m (100ft) or contain more than two 90 degree bends between pull points or pull boxes."


These 2 will be hard to accommodate. Wow, thnx for the info.
 
Shockedby277v said:
These 2 will be hard to accommodate. Wow, thnx for the info.
Not really. When you need your third bend, you put a straight through pull box right before (or shortly before) the third bend, and your bend count "resets". If this is an underground run, you install a handhole type enclosure with a mousehole in each end every 100 feet. Underground, you can "curve" the pipe over the entire run and maybe not need any bends, per se. One long curved run with a couple hundred foot radiused bend.
 
On a side note, we often field bend PVC 90's for low voltage out of most of the whole stick of pipe. Even if you're running something small like 1", use the 4" hot box to heat the whole stick. Seems like it keeps the pulling forces down, particularly on jobs where you need to document the pull forces for each cable as it's installed. For metallic raceways, this is one of the few times where I will segment bend a long radius ell. Just don't tease me if all my ells aren't exactly the same. Hicky bending is a lost art. I'm getting better.
 
Last edited:
568: 4.4.2.4 “Any single run, extending from a telecommunications closet shall serve no more than three outlets.” (an outlet can be a single jack on a plate. even if you ran 4", you can only have 3 cables in it) I would interpret this as not more than three outlet/jacks on any given cat5 cable, rather than not more than three cables in a given conduit.
I agree with the use of fewer cables or larger conduit than what the code would allow, example of Table C1 you're allowed to pull nine #12 thhn conductors in a 1/2" EMT, how many of us only ever tried that one time?
 
mdshunk said:
For your Cat5, the TIA-EIA 568 and 569 requirements are much more strict than the NEC. Here's a couple to see if they help:

568: 4.4.2.4 ?Any single run, extending from a telecommunications closet shall serve no more than three outlets.? (an outlet can be a single jack on a plate. even if you ran 4", you can only have 3 cables in it)
568: 4.4.2.6.3 ?Boxes shall be placed in a straight section of conduit and not used in lieu of a bend.? (no angle or U pull boxes)
569: 4.4.2.1 ?No section of conduit shall be longer than 30m (100ft) or contain more than two 90 degree bends between pull points or pull boxes."
569: 4.4.2.2 ?The inside radius of a bend in a conduit shall be at least 6 times the internal diameter. When the conduit size is greater than 50mm (2 inches), the inside radius shall be at least 10 times the internal diameter of the conduit. For fiber optic cable, the inside radius of a bend shall always be at least 10 times the internal diameter of the conduit?
I would interpret 568: 4.4.2.4 to mean that you cannot have more than three outlets/jacks on a given cat5 cable rather than not more than three cat5's in a given conduit.
I definitely agree with the use of larger conduit or fewer cables than NEC would allow. How many of us have referenced Table C1 to see that it's acceptable to pull nine #12-thhn's in a 1/2" EMT and only tried that one time?
 
jpresort said:
I would interpret 568: 4.4.2.4 to mean that you cannot have more than three outlets/jacks on a given cat5 cable rather than not more than three cat5's in a given conduit.
Except for that fact that the spec is in the raceway section, and the "run" they are talking about is a run of raceway. Sorry for the confusion. I was trying to keep a hard spec simple. Fact is, these specs might not even apply to most. They certainly don't have the force of law, but are often referenced in spec books, prints, and other contract documents. Just trying to help and generate discussion, is all.
 
jpresort said:
I definitely agree with the use of larger conduit or fewer cables than NEC would allow. How many of us have referenced Table C1 to see that it's acceptable to pull nine #12-thhn's in a 1/2" EMT and only tried that one time?


Hey, were you watching me?:D


Tom:smile:
 
Davis9 said:
Hey, were you watching me?:D


Tom:smile:
That's why I think 1/2" pipe has very little value, except for short runs to something in particular, like a single piece of utilization equipment, single receptacle, or a switch.
 
mdshunk said:
That's why I think 1/2" pipe has very little value, except for short runs to something in particular, like a single piece of utilization equipment, single receptacle, or a switch.


I hear you, sometimes I'll get a resi boiler that needs extra wiring and it can get tight!

Tom
 
Shockedby277v said:
Also does phone lines need to be seperated from other low voltage cables?
Be carefull with "low voltage" thats not a code term at all.
However, limited energy cables, from systems such as CATV, Art 725 Class 2 and 3, PL Fire Alarm, and telecom can be run together.
And you can run phone wire, such as Cat 5e in the same bored hole as an NM cable.
With conduit:
Wire fill is limited to 40%
Pulling tension is also important to limit.
 
For your Cat5, the TIA-EIA 568 and 569 requirements...

Anything from the TIA-EIA are NOT requirements, they are just their recommendations, biased at best, and do NOT carry any regulatory weight. Most people ignore them unless you are a IT person or a member of BICSI who love to paste those "requirements" into job specs.

The NEC does not specify fill requirements for low voltage cables. Conduit fill then is based on pulling tensions- how hard you can pull the cable without damaging it. The best place to find conduit fill recommendations is the manufacturer of the cable you are using. They made it so they should know.

Taking the diameter of a cable, comparing it to the same diameter THHN and then basing the fill on that is only going to get you in trouble. You can pull the heck out of THHN but do that with low voltage cable and it will be damaged.

-Hal
 
hbiss said:
For your Cat5, the TIA-EIA 568 and 569 requirements...

Anything from the TIA-EIA are NOT requirements, they are just their recommendations, biased at best, and do NOT carry any regulatory weight. Most people ignore them unless you are a IT person or a member of BICSI who love to paste those "requirements" into job specs.

You're right, Hal, which is why I said:

mdshunk said:
Fact is, these specs might not even apply to most. They certainly don't have the force of law, but are often referenced in spec books, prints, and other contract documents. Just trying to help and generate discussion, is all.
I don't want anyone to get the wrong idea and think I'm a BICSI nazi. Just trying to spice up what could be a boring conduit fill thread.
 
Marc, thanks for the input. Because of it i've looked at a couple of sites on cable requirements. Being new to this site i'm enjoying the shared information, especially when it's backed up with a reference to code or spec. John
 
Status
Not open for further replies.
Top