BECKHOFF BK3000 - Manual (Page 35)

PROFIBUS coupler BK3xx0 in the PROFIBUS DP
BK3xxx/LC3100 35
The FREEZE and SYNC capabilities are pre-set in the slave parameters,
(see figure), and can not be switched off. FREEZE and SYNC are
controlled by the controller software.
Switching on the communication monitoring ensures that, in the event of
the failure of a particular station, the master will generate an error
message, allowing the control software to initiate exception handling
routines. Communication monitoring can be individually selected for each
station. The communication monitoring is switched on as default setting.
The COM PROFIBUS software issues a warning if the monitoring is
switched off.
The asynchronous access of the control CPU (usually a PLC) to the
PROFIBUS master’s data area can give rise to inconsistencies. The
configuration of a “multiple byte signal” and module consistency in the
COM PROFIBUS configuration software for the IM308-C automatically
ensures data consistency. Please refer to explanations in the manuals from
the appropriate manufacturers for further master interfaces.
Common PLC connection types are the IM308-B and IM 308-C as Profibus
DP master and the CP5431 as DP and FMS master.
Detailed information regarding the IM308-B is contained in the ET200
Distributed Peripheral System Manual, order no.: 6ES5 895-6SE11 from
Siemens in relation to data exchange with the Siemens S5. The manual
explains the use of the ET200COM software. Rules for ensuring
consistency are described in Appendix B, “Access to the Distributed
Peripherals”.
A Windows program, COM PROFIBUS, and extensive descriptions are
available for the IM308-C Profibus DP master interface. For work with the
Siemens S5, the IM308-C has the advantage of improved handling and the
possibility of freely allocating the peripheral address bytes. Versions 2.1
and higher are particularly convenient. With them it is possible to read an
extended type file. The settings required to ensure data consistency are
automatically made by the entries in the type file. (The figures on the
previous pages are taken from the COM PROFIBUS software.)