Installation of ariel cable

Description of the ground condition along the route and distances rocky, sandy, grassy, clay, etc. Indicate the distance to the nearest town, where the civil works material sand, cement, stone, water, tools, etc. Plan the route to allow for projected road or rail deviations. Double-check recorded details on the return journey. Pre-Install Meeting A pre-install meeting or meetings must be held to discuss the survey results, the optimum pulling sites, span lengths, installation equipment and hardware requirements, logistics, splice locations, terrain and other vital installation topics.

Checks to be undertaken prior to commencing with the planned aerial work Does the contractor have approved aerial route drawings, signed by the client?

Do the drawings show the alignment of the aerial route within the wayleave specification? Are the wayleaves in place? Have the locations of existing services been marked and shown on drawings?

Has the accessibility of poles to splicing vehicles been considered? Does the cable have a UV resistant cable jacket? Wooden pole inspection prior to installation Correct type of pole supplied? Horizontal cracks perpendicular to the grain of the wood may weaken the pole. One large knot or several smaller ones at the same height on the pole may be evidence of a weak point on the pole. Inspect the pole for evidence of termites or ants.

The poles should never be off loaded and stacked on the ground for long periods as this could cause damage to the poles as well as the environment. The hammer will produce a clear sound and rebound sharply when striking sound wood. Decayed areas will be indicated by a dull sound or a less pronounced hammer rebound.

Hole-digging Tools The tools provided for hole-digging include picks, shovels, earth augers, crowbars, drills and sledge hammers. The tools to be used for any particular work are determined predominantly by soil conditions. On large projects and wherever ground conditions permit, hydraulically powered Earth Augers can be used.

It looks much like a corkscrew and produces extremely clean holes. Pole Holes Poles must be buried sufficiently deep for stability. The depth depends on the height of the pole. Check with local authorities to confirm these dimensions. All excavations for pole holes will be such that the survey peg indicates the center of the hole.

If the holes are too large, the soil will be unnecessarily disturbed and the poles will not be supported by solid earth. A diameter of approximately mm 16 inches is recommended. Where a hole is dug on sloping ground, the depth of the hole shall be measured from the lowest point on the ground surface. In extreme rocky conditions where holes cannot be excavated to the specified depth, an arrangement between contractor and client can be reached for poles to be set in concrete.

Poles set in Concrete Where poles are planted in soil that is difficult to compact, such as sand and swampy areas and in extreme rocky conditions, the poles can be cast in concrete. Only new wooden poles can be set in concrete.

The hole must be circular in shape. The hole diameter must be kept to a minimum, but be sufficiently wide to accommodate at least 85mm of concrete between the sides of the pole and the undisturbed ground.

The concrete to be used must be made from a mixture of 1 part cement, three parts sand and three parts crushed stone mix - 15MPa. Concrete must not be compacted around the poles, but thoroughly tamped around the pole with a suitable wooden stick, until the hole is filled. Pole Spacing It is advisable to maintain a uniform span length and depart from this only when it is rendered necessary by conditions such as: 1 uneven ground 2 sharp bends 3 or to avoid dangerous positions.

This may necessitate the planting of additional poles or omitting of poles. Steel measuring wires for standard span lengths should be made up locally. When the length of span has been chosen the appropriate wire should be used to determine the distance between successive poles. A steel tape measure should be used for checking the length of the measuring wire daily during the survey. Local ADSS Span Lengths All dielectric self-supporting fiber optic cable can be installed without a messenger over relatively long spans.

ADSS installation will be covered later. Pole Planting Process Ensure that all holes necessary for pole dressing are drilled prior to erection. A pole should be erected by laying it on the ground in such a position that by raising the top section, the base should slide into the hole. Backfilling and ramming must take place in mm 6 inches intervals.

Where stones are available they should be used to stiffen the holding. During the backfill and ramming process, always ensure that pole plumbness is maintained. Avoid obstructing private roads and entrances. Restrict road crossings to a bare minimum, and if possible, stick to the same side of the road throughout. Along national and other proclaimed roads the poles and stays should be located in the position agreed to by the Road Authority and as indicated on the wayleave.

Keep the route as far away as practically possible from power lines. Where the ground is very soft, poles may be planted mm 12 in deeper than specified, but only if the necessary vertical clearance is maintained. Ensure that all holes necessary for pole dressing are drilled prior to erection.

Maintain a distance of at least 1m from trig beacons and stations. The principle to be followed in all cases is that neither stays nor poles are to be planted where they are likely to cause obstruction or to be dangerous to users of the road, or where they are likely to interfere with ordinary road maintenance such as the clearing and trimming of the edges of the road or the cutting of drains, gutters, etc. In railway reserves, the poles should be located as close as possible to the boundary fence.

Types of Stays Terminal Stays Terminal stays are provided where the route starts and ends. This stay must be on the side of the pole opposite to the direction of the cable route. Line Stays Line stays should be installed at every 13th pole along the route or spaced alternatively as per specification. Line stays must be installed on poles either side of rivers and road crossings where normal span lengths are exceeded.

Step 7: Continue to install span by span until the entire run is completed and the final dead-end pole has been reached. Step 8: At this point, the cable should be tensioned to the correct sag level using suitable chain hoist equipment at the "free" end of the cable before it is dead-ended to the pole. Step 9: Finally, the cable can be lifted out of the temporary J hooks or temporary supports and permanently fixed using tangent assemblies.

The stationary reel method is generally used when the cable is installed above the existing lateral cable and other obstructions. The types of vehicles and available placing equipment will also depend on whether to use this method or not. The deployment procedure is as follows:. Step 1: Install a series of temporary cable supports, chutes, or tangent blocks at each pole along the route.

Step 2: Then, a pull line is threaded through the cable supports and attached to the outside of the cable using a breakaway swivel and a cable pulling grip.

It is then used to pull the cable through the cable blocks into position. Step 3: If the cable is pulled with a winch, the pulling rope or winch line must be installed through the cable supports. A non-metallic rope or winch line should then be used to pull the cable.

Step 4: When the installation tension exceeds the maximum rated cable load MRCL , the pulling winch should be calibrated to stop the operation.

A dynamometer with an audible alarm or visual display should be used to monitor installation tension in case this type of winch isn't available. Step 5: After the cable has been pulled into its final position, with slack for building access or for splicing, the cable should be tensioned until the correct sag level is reached. Then it should be terminated at each dead-end pole along the route. Work doesn't finish completely after aerial fiber optic cable installation.

Post-construction inspection is also important for a successful cable deployment. Check the following items to examine whether your installation is successful. Before splicing, inspect the aerial cable plant thoroughly, especially pay attention to the exact location of all splice points.

Presence of kinked or damaged cable. Figure 8 self-supporting aerial fiber optic cables are the common ADSS cables designed for easy and economical one-step installation over long haul network communication.

According to different aerial cable types, there are generally two installation ways. First is to lash a fiber optic cable to a steel messenger. A steel messenger is first installed between the poles. Then a cable reel trailer and truck are used to pull the cable along the messenger.

A cable guide and cable lasher are used to wrap around both the messenger and the fiber cable to secure the fiber cable to the messenger. Following the cable lasher is an aerial bucket truck which makes necessary adjustments.

At each pole, the fiber optic cable forms an expansion loop to allow for expansion of the messenger. The fiber cable should also maintain its minimum bending radius at all times.