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ÖLFLEX

®

ACCESSORIES

FLEXIMARK

®

SILVYN

®

SKINTOP

®

EPIC

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HITRONIC

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ETHERLINE

®

UNITRONIC

®

APPENDIX

For current information see:

www.lappgroup.com

1211

Appendix

Glossary

winders, axial winders and barrel winders. Depending on their flexural

loading, tensile strain, torsional strain, design, storage, mechanical

load and transport, cables are individually wrapped and delivered on

drums, bobbins, in coils or barrels.

Talcum

Talcum is a mineral, slightly fatty natural product. It is used in powder

form as a separating agent or lubricant. It is also used when mixed with

mica. When sheathing a strand of cores, to prevent the sheathing

material that is applied when hot from sticking to the core insulation,

the strand is dusted with talcum first. As well as the separating effect,

this greatly reduces the friction between the individual elements of the

cable and thus promotes flexibility and stripping.

Tape

The stranded assembly, comprising several cores, is surrounded by the

tape. Generally, the tape is made from one or several synthetic or

paper band layers.

Tape wrapping

Cables can be wrapped in a variety of different insulating materials.

The tape is always helically wrapped around the cable as the taping

machine operates in a rotary motion and the pull-off movement is

always in a longitudinal direction. Several layers of paper or plastic

tape are wrapped around the cable stranding or the cable core.

TDR

The Time Domain Reflectometry measuring method is used to locate

faults in copper cables. The running time and shape of a reflected pulse

enables the possible location of the fault to be determined relatively

accurately. For PVC insulated cores, this value is approx. 0.541.

Telephone cord

Cables to or in telecommunication devices which have a high flexural

loading or flexibility.

Temperature range

If the specified minimum temperature range is not reached, no

mechanical forces may act on the cable as otherwise the insulation will

break (rigidity of polymer chains). If the maximum temperature is

exceeded, the insulation begins to melt (decomposition of polymer

chains). Important! With every change of temperature, the resistance

of the conductor also changes.

Tensile load

The maximum force with which a cable can be loaded under defined

conditions.

Test voltage

The voltage applied to a test specimen to demonstrate a particular

electrical strength.

Tex

The fineness of fibres is determined using the “fineness in Tex” system.

This is a physical variable. 1 Tex = a fibre that has a mass of 1g at

a length of 1000 m. Example: Polyester silk has a rating of 7 Tex =

1000 m of silk weighs 7 g.

Thermal splice

A thermal splice is a connection between light waveguides created

by fusing the ends of the conductors.

Thermoplastics, thermoplastic materials

Thermoplastics are non-cross linked macromolecular compounds.

By heating, it is possible to transfer them repeatedly to a plastic condi-

tion. They are primarily used for sheathing and insulation of cables.

Thomson measuring bridge for resistance measurement

Primarily used to measure very low resistances. The measuring range

is between 10-6 and one Ohm. It is independent of voltage changes.

The measured result is not falsified by the resistance of the measuring

lead and other transition resistances (see also → Electrical resistance).

Tight buffer tube

Fibre type used in light waveguides, with a solid plastic layer attached

directly to the outer glass.

Tin

Tin is used for tin plating copper wires.

Torsion

Twisting of the cable about the longitudinal axis. VDE0298, Part 300,

Section 5.4.4: Flexible cables are not generally intended for torsional

loads. In cases where this kind of torsional load cannot be avoided, the

construction of the cable and the type of installation must be agreed

between the user and the cable manufacturer.

Tracer thread

A thread whose structure, colour or colour combination is registered

and protected as a trademark by a cable manufacturer. It provides informa-

tion about the manufacturer of the relevant cables (at Lapp, the colour

is ochre yellow).

Train signal cable

Designed for voltages up to 600 V. Depending on their purpose, the

cores are twisted in fours or layers. They are PE insulated. Because of

the strong electromagnetic fields on railways, an effective copper

screen and steel tape armouring must be fitted under the outer sheath.

Transceiver

This is the active component of an Ethernet LAN for connection of termi-

nals to the electrical bus cable with collision detection and signal adap-

tation functions. Transceiver is a combination of the words transmitter

and receiver. The transceiver performs transmitting, monitoring, recep-

tion and interference functions.

Transfer impedance

Measure for the quality of the screening, defined as the ratio of the

voltage along the screening in the system subject to interference to the

current of the system causing the interference. The transfer imped-

ance (coupling resistance) is the key variable for the quality of the

screen and depends on the frequency. It is the ratio of the voltage drop

along a screen on the side with interference (outside) to the interfer-

ence current on the other side (inside) of the screen. The coupling

resistance is determined by the construction of the screen, the skin

effect and the capacitive coupling.

Transfer rate

The frequency at which the level of the transmission function of a light

waveguide has reduced to half of its value at a frequency of zero, i. e.

at which the signal attenuation has increased by 3 dB. As the transmis-

sion bandwidth of a light waveguide is approximately the reciprocal of

its length (mode mixing), the bandwidth/length product is often specified

as a quality feature.