VIPA SLIO IM 053-1DN00, Руководство пользователя

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Manual VIPA System SLIO Chapter 3 Deployment
HB300E - IM - RE_053-1DN00 - Rev. 11/21 3-3
DeviceNet employs a screened five-core cable as data communication
medium. DeviceNet uses voltage differences and for this reason it exhibits
less sensitivity to interference than a voltage or current based interface.
Signals and power supply conductors are included in the same network
cable. It is therefore possible to connect devices that obtain the operating
voltage via the network as well as devices with an integrated power supply.
Furthermore it is possible to connect redundant power supplies to the
network that guarantees the power supply when required.
DeviceNet employs a master line/tap line topology with up to 64 network
nodes. The maximum distance is either 500m at a rate of 125kbit/s, 250m
at a rate of 250kbit/s or 100m at a rate of 500kbit/s.
The length of the tap lines can be up to 6m while the total length of all tap
lines depends on the baud rate.
Network nodes can be removed from or inserted into the network without
interruption of the network operation. New and failed stations are detected
automatically.
DeviceNet operates according to the Carrier-Sense Multiple Access
(CSMA) principle, i.e. every station on the network may access the bus
when it is not occupied (random access).
The exchange of messages is message orientated and not station
orientated. Each message is provided with a unique and priorizing
identifier. At any time only one station is able to occupy the bus with its
messages.
The DeviceNet bus access control is subject to non-destructive, bit-wise
arbitration. In this case non-destructive means that the successful station
participating in the arbitration doesn't need to re-send its message. The
most important station is selected automatically when multiple stations
access the bus simultaneously. If a station that is ready to send recognizes
that the bus is occupied, its send request is delayed until the current
transfer has been completed.
All stations on the bus must be uniquely identified by means of an
ID address. Every DeviceNet device has addressing facilities.
From VIPA there are EDS ( E lectronic D ata S heet) files for the DeviceNet
coupler available. These files may either be found on the supplied storage
media or at the download area of www.vipa.de.
Please install the EDS file you require in your configuration tool. Details on
the installation of the EDS file are available from the manual supplied with
your configuration tool.
Communication
medium
Bus access
method
Addressing
EDS file