Agtec Telecoms - Earthing & Lightning

Where deep driving is not possible shorter rods with a larger diameter can be used; copper earth mats and earth plates can be used in place of earth rods.

A "crow's foot" configuration can be used where parallel connection is not possible.

Where high resistance soil conditions are a problem soil conditioning agents can be used to backfill rod holes. Conductive concrete can be used to backfill an earth mat. Both effectively increase an electrodes cross sectional area and therefore reduce its resistance to earth.

The international standards also specify the recommended materials used for all earthing conductors and their dimensions.

tower mast coupling

Equipotential Bonding
It is common practice to use the buildings natural structural steelwork and bonding it to the LP8 to further improve its ability to conduct lightning and fault currents to earth; prior permission may be required.

u bolt connector clamp

Joints
Joints should be mechanically effective, all joints other than welded ones are a potential discontinuity, and care should be taken to ensure contact surfaces are clean and that fixing clamps are tight and well protected from corrosion, which can occur if dissimilar metals are joined. Ideally there should be as few joints as possible in an earthing design.

Maintenance &life of an earth system
It is important to properly maintain an earth circuit to ensure it retains its ability to conduct the same current carrying capacity as it did when it was originally installed. Earth rod resistances should be regularly checked. Corrosion and fault currents can cause high resistance joints leading to overheating. However, if an earth system is correctly installed and maintained it should last for many years.

The information contained in this section is intended as a guide and should not be used to perform designs. A.N.wallis does not accept responsibility for errors or omissions. Detailed information on earthing design is contained in internationally recognised European and British earthing standards. e.g. B87430, B87671.

pvc covered tape, flexible copper braids, solid circular conductors

pvc covered tape, flexible copper braids, solid circular conductors

•Optical and mechanical:
•Mode field diameter at 1310 nm	[μm]	9.2 ± 0.4
•Cladding diameter	[μm]	125.0 ± 0.7
•Coating diameter	[μm]	245 ± 5
•Attenuation at 1310 nm	[dB/km]	≤ 0.36
•Attenuation at 1550 nm	[dB/km]	≤ 0.22
•Attenuation at 1383 nm	[dB/km]	≤ 0.36
•Dispersion in the range 1285 to 1330 nm	[ps/(nm*km)]	≤ 3.5
•Dispersion at 1550 nm	[ps/(nm*km)]	≤ 18
•Cable cutoff Wavelength (λcc)	[nm]	≤ 1260
•The fibers are fully in compliance with ITU-T G.652.D and annexes. •Other options are available on request.

A survey is required to determine ground resistivity.
Soil moisture content: more moisture always reduces soil resistance.
Chemical composition of soil: certain salts and minerals affect soil resistivity.
Temperature: if the ground is frozen its resistance becomes much higher.
The extent of any buried services which could affect the earth termination networks.
Details of metallic service pipes, rails, tanks etc. which may need bonding into the earth system to prevent the danger of side flashing.
The area available to place earth electrodes, this may be limited.

Characteristics of fibers E9/125 SMF 28e™ – low water peak fiber -

Characteristics of fibers G50L/125 InfiniCor 600® = OM2

CCS reserves the right to improve, enhance, and modify the features and specifications of CCS’s products without prior notification. The information in this data sheet has been reproduced in good faith and is accurate, to the best of CCS’s knowledge, at the time of printing. However, CCS makes no warranty as to, and will not be liable on any basis for, the information contained within this data sheet.