2Telecom Cabling Outside plant cables are covered by NEC article 800. Standard TIA/EIA 758 covers customer owned outside plant.Be aware that no one is allowed to go into a manhole or other confined spaces without first being certified for confined spaces.
3Telecom Cabling There are only three methods for cabling outdoors; Aerial (telephone poles)Underground (manholes and tunnels)Direct burial (cables placed in a ditch)
4Telecom CablingLets see what is on a telephone pole, or more accurately a joint pole sincepower, telephoneand CATV allshare the sameutility pole.
5Telecom CablingLets take a closer look at the communications part of the pole, the space between power and communications is designated as the safety zone space.
6Telecom CablingThe safety zone space protects communications personnel from dangerous voltages (even if a technician "forgets" to wear a hardhat).
7Telecom CablingThe CATV cable in most cases is at the bottom or below the communications cable, you can see this driving down almost any road, especially in residential neighborhoods.The signature CATV loop
8Telecom CablingCommunications and CATV hardline cables are supported by a messenger strand and lashing that is spiraled around the cable.Why do these cables need a support strand if they already have an armored sheath?
9Telecom CablingThe messenger strand is used to support the cables in high winds and for ice and snow loads.The metal strand is what gets connected to the telephone poles.The metal strand is galvanized for corrosion protection and can be used to lash several cables together.
10Telecom CablingHere is something else you’ve probably noticed while driving down the street or looking out your window.
11Telecom CablingWhat is the purpose of the loop that is formed into the CATV trunk cable?
12Telecom CablingThe loop is an expansion loop that absorbs expansion and contraction caused by temperature variations.
13Telecom CablingThe CATV network is an HFC (hybrid fiber coax) network.By building out the CATV networks with fiber optics the need for amplifiers to boost the signal over the copper cable is reduced.Amplifiers are required for every ½ mile to a mile apart and this creates many failure points in the network.
14Telecom CablingAs a CATV installer the tap is something that you will be accessing to provide service to a home, when cable service is turned on or off its suppose to be done at the pole.
15Telecom CablingThe round barrel looking devices are copper and fiber splice enclosures.
16Telecom CablingUnderground cabling as stated before requires certification before a technician can go into a manhole.There are many cabling companies that perform underground cabling services and this type of install requires a lot of heavy duty equipment.
17Telecom CablingThe first thing to do is lift the manhole cover, these things can weigh 100lbs and require a special tool.Why are manhole covers round?Manhole cover puller
18Telecom CablingManhole holes are to be guarded with a gate and fresh air needs to be pumped into the hole.Many times however the water needs to be pumped out of the hole.Blower fan and hole to pump fresh air inSafety gate and cones
19Telecom CablingA tripod must be on sight to retrieve any one who gets injured or passes out in the manhole
20Telecom CablingIn order to pump out the water and blow in fresh air you will need a generator to provide the power needed run the pumps and blowers.You may have to snake the 4” conduits from one manhole to the other, for that weuse the super sized snake calleda duct rod which is a ½”fiberglass snake.
21Telecom CablingOnce the conduits are snaked we drag a ½” to 1” rope through, the size of the rope is determined by the size of the cable to be installed.Sometime we install mule tape which has footage markings on it an can also be used to pull fiber and smaller trunk cables.
22Telecom CablingOnce we have our rope in place we are ready to pull cable.To pull our high count cables (200, 300, 600 and 900 pr.) we prep the cable with a pulling grip, these work like the Chinese finger traps.
23Telecom CablingIt is critical that when you tie rope onto the pulling grip it will not slip off or pull apart.When splicing rope or attaching two lengths of string or rope together it is done so that the knots do not pull apart, knots should be simple, strong and small (streamlined).If your knot pulls apart it could mean hours of wasted time, knots pull apart in the middle of the conduit, in OSP that mean re-snaking feet of pipe.
24Telecom CablingTo ensure that the cable doesn’t get damaged we use a cable shoe and cable sheave (pulley) secured to an anchor point in the manhole.This goes over the lip of the manhole.
25Telecom CablingWhen pulling an underground cable into a building we may end up using a super tugger.This gets anchored to the floor and is used to pull heavy cable by making three rope wraps around the capstan.Three wraps of rope around the capstan for easily tightening and loosening of the rope during pulling.
26Telecom CablingSome of the cable reels for OSP cable are huge.
27Telecom CablingWhat is the maximum allowable length of cables entering buildings from outside?Do cables entering buildings from outside need to be grounded?
28Telecom CablingAccording to NEC and the TIA/EIA standards cables can not exceed more than 50 feet of length upon entering a building from outside.NEC article ; The metallic sheath of communications cables entering buildings shall be grounded as close as practicable to the point of entrance or shall be interrupted as close to the point of entrance as practicable by an insulating joint or equivalent device.
29Telecom CablingCopper cables entering a building must be placed on primary protectors and the chassis of these devices must be grounded with a 12 AWG.GROUND CONNECTION
30Telecom CablingUnderground cabling will almost always involve a cable splice somewhere along the length of the run, your cable will need to be tapped into a trunk line.900 pr. cable splice (super binders)
31Telecom CablingWhen installing fiber backbones in any type of cabling environment (inside or outside) it may become necessary to back feed the cable or pull a lot of slack.When we back feed we figure 8 the cable then flip the figure 8 to start the pull again, this technique can be used with any type of cable.The figure ensures the cable won’t get tangled during a pull and flipping it allows the cable to feed off from the top.
32Telecom CablingDirect burial cabling is similar to underground cabling with the exception that there are no manholes involved.Direct burial systems can be conduits run to hand holes or the cable would be directly buried without conduit.
33Telecom CablingDirect burial systems utilizing conduit and hand holes require much of the same equipment used for installing cables through manhole systems.What color is direct burial cable?All direct buried and underground cable and the majority of aerial cable is armored, why?
34Telecom CablingSome terminology to be aware of; a service drop is an aerial cable from a pole to a building, this is defined in NEC article 100 definitions.A service Lateral is an underground cable that enters a building, also define in article 100 of the NEC.
35Telecom CablingWhen installing a drop from outside into a building the installer must leave a drip loop on the cable and seal the hole with weather proof caulking.