The communication
between control station and basic automation (PLC, DDC,
RTU) is executed in WinCC OA
through own managers, the so-called drivers. Depending on the
communication protocol and the used bus physics, specific drivers
are used.
Seriel protocols: RK512, 3964R, Muehbus,...
Field bus: Profibus DP, Profibus FMS, ...
Ethernet: ModbusTCP (OpenModbus),
Industrial Ethernet (S7), Ethernet IP (AB)...
Telecontrol system: SSI
(Ethernet), IEC 60870-5-101, IEC 60870-5-104,....
Multivendor interfaces:
OPC DataAccess, OPC Alarms&Events
An arbitrary, vendor-specific communication form
(protocol, bus physics) is adapted to the general WinCC OA communication form
by a driver manager.
This a standardization where the driver process executes a number
of tasks already automatically.
Adjustment
to the bus physics
(PCI card, low-level driver, TCP stack, ...)
Decoding
of the communication protocol
(evaluation of telegrams / frames)
Connection
monitoring
Automatic
old-new comparison
(Low-Level smoothing)
Value
and time-dependent smoothing (more significant smoothing)
Data type-Transformations
Transition
of arbitrary communication form to event-oriented
data exchange
Add a driver in the same way as each other manager
to the start list of the
console. Subsequently, you have to configure
the drivers individually. These necessary processes are
described in the online help in the chapter driver.
Figure: Manager properties of a
driver
Without taking further steps, all existing data
point elements are internal:
merely the different managers of WinCC OA
can read or write their values. The data is not exchanged automatically
with the base automation (PLC, DDC, RTU).
In order to receive values for a
data point element from an external device, for example
PLC, assign a peripheral address
in the form of a config to this element. You can assign
a peripheral address as follows in the database editor PARA:
Add a
corresponding config
(_address) or PowerConfig
to a data point element
Select the driver to be
used individually (for example WCCOApr for Profibus DP or
Profibus FMS)
Enter
the hardware or bus specific address
(for example '%MW1021' for Modbus TCP in conjunction
with Schneider Premium or Quantum PLCs)
Enter the data direction
and for some protocols also the type of access (input, output,
input/output).
NOTE
In this example, the driver that exists by
default "WCCILsim" was used. It serves as a form
of placeholder as long as you do not configure any real drivers.
In order to configure driver-specific settings, at
least this simulation driver has to exist. Consider
that only one driver with the same number (for example
-num 2) is active at the same time. In order to run a driver with
the number 1, you have to deactivate the by default existing SIM
driver (if you don't specify the driver number, it does automatically
mean -1 internal).
NOTE
How to connect to a programmable controller
of the basis automation, see chapter driver
of the online help.
You can run several
drivers simultaneously in WinCC OA.
These can be of the same but also of a different
type. For example, it's possible to establish connections
to a Simatic controller via the S7 protocol, to a telecontrol
system via IEC 60870-5-104 and to an arbitrary OPC server
via OPC DA . |