Technische Alternative UVR65, Руководство пользователя: программы, установка, подключение к электросети

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CAN-Bus network
Terminal CAN-Bus line
Guidelines for the topology of a CAN network
Technical principles
The CAN BUS comprises the cables CAN-High,
CAN-Low, GND and one +12 V supply cable for
bus components without their own power sup
-
ply. The combined total load of all devices with
12 V and 24 V supply must not exceed 6 W.
Design CAN networks in a linear fashion and
set a terminator at each network termination.
This is ensured by the termination of the end
devices.
In the case of larger networks (covering sever
-
al buildings), problems can occur through elec -
tromagnetic interference and potential
differences.
To avoid or to the greatest extent manage
such problems, take the following measures:
• Cable screening
The BUS cable screen must be connected well at every node to provide continuity. For larger
networks we recommend including the screen in the equipotential bonding, in line with the
examples shown.
• Equipotential bonding
The lowest possible ohm connection to the earth potential is particularly important. Where
cables enter buildings, ensure that the cable entries are in the same location where possible
and that all are connected to the same equipotential bonding system (Single-entry-point
principle). The purpose is to create potentials that are as similar as possible, in order to
achieve the smallest possible potential difference to adjacent lines in case one line suffers a
voltage surge (lightning strike). Also ensure a corresponding clearance between the cable
and lightning protection systems.
The equipotential bonding also has positive properties to counteract interferences emitted
from linked cables..