Siemens SICAM CMIC, Руководство пользователя

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SICAM RTUs, User Manual SICAM CMIC
405
DC8-001-2.09, Edition 08.2016
Glossary
A
Adress type
The address type defines if a system-technical or a process-technical address is entered as address of a
datapoint in a message
Analog input
Hardware for the acquisition of an analog signal via measuring transformer (measured value via current,
voltage, temperature, resistance)
Analog input module
Module (submodule, I/O module, etc.) to acquire analog signals. Task of an "analog input" is the evalua-
tion of analog signals, and consequently the recuperation of the analog process information items. De-
pending on the comprehension of the term, the adaptation is also included or not.
Analog output
Hardware for the output of an analog signal to a display equipment (measured value) or to the setpoint-
value input to an actuator (current, voltage)
Analog output module
Module (submodule, I/O module, etc.) for the output of analog signals. Task of an "analog output" is the
transformation of arithmetical values to currents or voltages, and consequently for the output of analog
process information items.
Application program
Logical arrangement of all program language elements and constructs, that are required for the intended
signal processing for the control of a machine or of a process with a PLC system (acc. to
IEC 61131-12.1).
With CAEx plus application programs for open-/closed-loop control functions are created. An application
program comprises the task(s) and the related program instances and type instances. An application pro-
gram is executed by a resource (
ž
CPU).
Application service data unit
The application service data unit (ASDU) is composed of a data unit identifier and a information object.
The data unit identifier has always the same structure for all ASDUs and consists of 4 octets. Its structure
is as follows:
• Type identification
• Variable structure qualifier
• Cause of transmission
• Common address of ASDU
The common address of ASDU shall normally be identical to the address used in the link layer. The infor-
mation object consists of an information object identifier, a set of information elements and, if present, a
time tag. The information object identifier consists of 2 octets. Its structure is as follows:
• Function type
• Information number
ASDU
ž
Application Service Data Unit
Assign
Linking of datapoint-related information with the object, with that the functions process such information.
At data sources and data sinks of a data stream, datapoint-related information is inserted to or extracted
from the datastream by means of messages. At a source, this information is provided by a function, at a
sink it is utilized by a function.
AU
ž
Automation Unit
Autonomy
An autonomous basisc system element and its supplementary system elements (protocol and peripheral
elements) continue working during a failure of the master control unit