Omron SYSMAC CJ1W-PRM21, Руководство по эксплуатации

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Configuring the Slave Stations
Section 6-3
Apart from the I/O module selection, the Configuration tab also contains the
settings for two other parameters.
1. Enable Watchdog Control
This parameter will enable/disable the monitoring of the Master-Slave
communication in the slave device. If enabled, the slave will stop I/O data
exchange with the Master, if the Master has not send any request message
to the slave, within the configured Watchdog time. Furthermore, the slave
will
• switch its outputs to a known state.
• signal its change of state in a diagnostics message, the next time the
Master addresses the slave.
• request re-parameterization from the Master, before resuming I/O data
exchange.
If disabled, the slave will remain in data exchange, even if the Master is not
communicating, thus maintaining its outputs in the latest known state,
based on the last I/O data exchange message.
2. Watchdog Interval
This value is the watchdog timeout related to the Master-Slave communi-
cation time out.
Note 1. Enabling the watchdog Control is highly recommended for safe operation
of the network.
2. In the current version of CX-Profibus, the watchdog value for each of the
slave devices is overruled by the value determined by the Master Unit.
Therefore, changing the value in the Generic Slave DTM has no effect.
When done, making the I/O Configuration settings, press the Apply button at
the bottom of the window. Next, select the Parameter tab, to make the neces-
sary parameter selections.
6-3-2 Setting Parameters
The parameters are sent by the Master Unit to the slave device prior to estab-
lishing I/O data exchange. If the parameters are incorrect, the slave device will
reject them and not establish I/O data exchange, unless the parameters are
changed.
In general there will be two types of parameters.
• Common Parameters
Most of the slave devices require at least the common parameters. These
settings usually apply the whole slave system.
• Module Parameters
Modular slaves often apply parameters related to a specific I/O Module,
e.g. the physical slave device consist of a number of hardware modules,
each defining an amount of I/O data, and each requiring its I/O module
selection and that each module requiring its own parameters.
Example The Parameter tab of the CJ1W-PRT21 is shown in the figure below. It lists
the common parameters for the CJ1W-PRT21.