Omron CJ1W-PRT21, Руководство по эксплуатации

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1 Features and System Configuration
1-4
CJ-series PROFIBUS Slave Unit Operation Manual for NJ-series CPU Unit (W510)
 RS-485 Transmission Speed
Transmission speeds between 9.6 kbps and 12 Mbps can be selected. One unique transmission
speed must selected for all devices on the bus when the system is commissioned.
 Cable Length
The maximum cable length depends on the transmission speed. The specified cable lengths are
based on type-A cable (see
2-3 Network Installation ). The length can be increased by the use of
repeaters. The use of more than 3 repeaters in series is not recommended.
To achieve straightforward configuration of a PROFIBUS-DP network, the characteristic features of a
device are specified in a file. This file is called a GSD-file (Gerätestammdaten file).
GSD files are usually supplied with each unit. Alternatively, GSD files can be downloaded from the
Internet, either from the manufacturer's site, or from the GSD library of the PROFIBUS Nutzerorganisa-
tion at the following web site:
http://www.profibus.com
The device data base file of each device is loaded in CX-ConfiguratorFDT and downloaded to the mas-
ter device. Refer to the
CJ-series PROFIBUS Master Unit Operation Manual or NJ-series CPU Unit
(Cat. No. W509) for usage of the GSD file in the master's configuration software.
 GSD File Language
The language used in the GSD file is indicated by the last letter of the file extension, *.GS?:
Default = GSD
English = GSE
German = GSG
Italian = GSI
Portuguese = GSP
Spanish = GSS
The GSD files are prepared individually by the vendor for each type of device, according to a fixed
format. Some parameters are mandatory, some have a default value and some are optional. The
device data base file is divided into three sections
1
General Section; this section contains the vendor name, the device name, hardware- and soft-
ware release versions, device type and identification number, protocol specification and sup-
ported baud rates.
2
DP-master Section; this section contains all parameters which only apply to DP master devices
(e.g. maximum memory size for the master parameter set, maximum number of entries in the
list of active devices, or the maximum number of slaves the master can handle).
3
DP-slave Section; this section contains all specification related to slaves (e.g. minimum time
between two slave poll cycles, specification of the inputs and outputs, and consistency of the I/O
data).
1-1-3 GSD File Technology