Product Manual

3
Technical Specifications and
Characteristics of Leica
Geosystems Cables
Gerhard Soenser
Abstract
This paper presents an overview of the different
factors regarding cables that should be considered by
the surveyor in order to ensure the highest quality
and best system performance.
This document describes the materials used to
manufacture a cable, the criteria by which the
materials were selected and the regulations and
guidelines that a cable must fulfill in order to comply
with the requirements for being an approved Leica
Geosystems cable.
Introduction
Cables – in particular data transfer cables - are an
important and yet often overlooked component of a
complex measuring system.
During product development, the selection of the
right cable, outer jacket and plug is crucial to
achieving the desired overall performance.
The Leica Geosystems range of cables consists of
three basic types.
 Data transfer cables
 Power supply cables
 High-frequency antenna cables
Data transfer cables may be classified as serial
(RS232) or USB data transfer cables. Each of these
may be further classified as low, full or high-speed
cables, depending on their data transfer rate.
Almost all of these cables are also available in the
form of Y-cables.
Anatomy of a cable
Plug-in connectors
All Leica data and power supply cables for use in an
outdoor environment are fitted with LEMO® plugs.
LEMO® is a respected market leader in the design
and manufacture of custom-made solutions for
precision plug-in connections. These high-quality
push-pull connectors find use in a large number of
areas of application that call for the highest quality
requirements.
LEMO® connectors are deployed in orbit 36,000 km
above the earth and 600 m below sea level as well as
in temperatures of +500°C and -200°. The largest
fields of application are testing and metrology,
biomedical engineering, radio/television and
communications
Cable outer jacket
The second most important component of a cable is
the outer jacket. Of course the insulation must
protect the cable and the user from electric shocks
and short-circuits. These are functions that every
user knows.
But very few users know that all Leica cables have
been designed and tested to ensure that they
continue to fulfill their functions under the most
unfavorable conditions. At Leica all cables are tested
at regular intervals to ensure that they can withstand
storage temperatures of -40°C to +70°C. The cables
have to function within an operating temperature
range of -40°C to +65°C.
Cable strands
The most fundamental factor in the design of a cable
is the choice of the right cable type and material.
A cable for transmitting signals may have five to eight
conductors, depending on its purpose. Each
conductor consists of up to 44 individual strands of
copper wire. The strands may be arranged in
different ways to make up the conductor. Signal
cable conductors are often wrapped in a shield,
either in pairs and/or all together.