turck 6827380, Instructions For Use Manual

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Guidelines for Electrical Installation
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Cable routing outside buildings
Outside of buildings, cables should be routed in closed (where possible), cage-type cable ducts
made of metal. The cable duct joints must be electrically connected and the cable ducts must be
earthed.
9.1.3 Lightning protection
The cables must be routed in double-grounded metal piping or in reinforced concrete cable ducts.
Signal cables must be protected against overvoltage by varistors or inert-gas filled overvoltage
arrestors. Varistors and overvoltage arrestors must be installed at the point where the cables enter
the building.
9.1.4 Transmission media
For a communication via Ethernet, different transmission media can be used:

coaxial cable
10Base2 (thin coax),
10Base5 (thick coax, yellow cable)

optical fiber (10BaseF)

twisted two-wire cable (10BaseT) with shielding (STP) or without shielding (UTP).
9.2 Potential relationships
9.2.1 General
The potential relationship of a Ethernet system realized with BL20 modules is characterized by the
following:

The system supply of gateway and I/O-modules as well as the field supply are realized via one
power feed at the gateway.

All BL20 modules (gateway, Power Feeding and I/O-modules), are connected capacitively via
base modules to the mounting rails.
WARNING
Insufficient lightning protection measures
Risk of death due to lightning strike
† When installing cables outside buildings, observe all applicable guidelines for internal
and external lightning protection and all earthing regulations.
NOTE
Turck offers a variety of cable types for fieldbus lines as premolded or bulk cables with dif -
ferent connectors.
The ordering information on the available cable types can be taken from the BL20-catalog.