Renu Electronics GWY-500, Руководство пользователя

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Getting Started
16
Doc No: UMAN\GWY-500-B\0106
REVISION 4
3.1.3.2 Data Throughput
Transmission time At 12 Mbit/s, PROFIBUS-DP requires only about 1 ms for the transmission of
512 bits of input data and 512 bits of output data distributed over 32 stations.
The figure below shows the typical PROFIBUS-DP transmission time depending
on the number of stations and the transmission speed. The data throughput
will decrease when more than one master is used.
3.1.3.3 Diagnostic Functions
Extensive diagnostics The extensive diagnostic functions of PROFIBUS-DP enable fast location of faults
The diagnostic messages are transmitted over the bus and collected at the
master. These messages are divided into three levels:
Device related diagnostics 1. Device related diagnostics
These messages concern the general operational status of the whole device
(e.g. overtemperature or low voltage).
Module related 2. Module related diagnostics
diagnostics These messages indicate that a fault is present in a specific I/O range (e.g. an
8-bit output module) of a station.
Channel related 3. Channel related diagnostics
These messages indicate an error at an individual input or output (e.g. short
circuit on output 5).
3.1.3.4 Protection Mechanism
Time monitoring PROFIBUS-DP provides effective protection functions against parameterisation
errors or failure of the transmission equipment. Time monitoring is provided
at the DP master and at the DP slaves. The monitoring interval is specified
during the configuration.
At the master 1. Protection mechanism at the master.
The DPM1 master monitors data transmission of its active slaves with the
Data_Control_Timer. A separate control timer is used for each slave. This timer
expires when correct data transmission does not occur within the monitoring
interval.
If the master’s Auto_Clear mode is enabled, the DPM1 exits the ’Operate’
state, switches the outputs of all assigned slaves to fail-safe status, and
changes to its ’Clear’ state.