BST ekr CON 600 net - Electrical Connection; Electrical Safety Instructions

Design and Function
2
ekr CON 600 net – Process Data Exchange via Profibus 13/79
2.3.2 Device Types
A Profibus system consists of different device types (see illustration).
Slave
ekr CON 600 net
PLC, mashine control
Master (Class 1) Master (Class 2)
PC
Fig.7: Profibus device types
■ Class1 Master
A class1 master is a control unit that controls the automation
task and checks the cyclic data traffic on the bus. The master
exchanges process data with the slaves in a specified message
cycle. It may send unsolicited messages, if it has the authoriza-
tion for bus access. In a networked web guiding system with
Profibus connection, the customer control system (e.g. PLC or
machine control) acts as a class1 master.
■ Class2 Master
A class2 master is an engineering tool, typically based on a PC,
or an operating device that can access the bus cyclically and
that is used to parameterize and diagnose the intelligent field
devices.
■ Slave
A slave is a peripheral device whose task is to read input
information and to deliver output information. A slave does not
have authorization for bus access, i.e. it may only acknowledge
received messages or transmit messages to a master on its
request. In a networked web guiding system with Profibus-
connection, the ekr CON 600 net controller acts as a slave,
which is controlled by the customer control system. The signal
exchange with the different web guiding components (e.g.
sensors, actuator, ...) takes place using the inputs and outputs
of the web guiding controller.