Endress+Hauser Prosonic S FMU95, Руководство по эксплуатации

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Operation Prosonic S FMU95
30 E Hauser
Acyclic communication with a Class 2 master (MS2AC)
In the case of MS2AC, a Class 2 master opens a communication channel via a so-called service
access point (SAP) in order to access the device. Class 2 masters is for example:
• FieldCare
Before data can be exchanged via PROFIBUS, however, the Class 2 master must be made aware of
the parameters contained within the field device. This can be done by:
• a device description (DD)
• a device type manager (DTM)
• a software component within the master, which accesses the parameters via slot and index
addresses.
!
Note!
• The DD or DTM is supplied by the device manufacturer.
• The Prosonic S has two Service Access Points. Therefore, it can be simultaneously accessed by
two Class 2 masters.
• The use of a Class 2 master increases the cycle time of the bus system. This must be taken into
consideration when the control system or PLC is programmed.
Slot-Index tables
The Slot-Index tables for the general acyclic data exchange are summarized in the document
BA00346F on the enclosed CD-ROM (can be downloaded from www.endress.com).