B&R 5PP551.0573-00, User Manual

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Glossary
244 Power Panel 500 User's Manual V 1.00
7 Glossary
Address
An address is a character string for identifying a memory location
or a memory area, where data is stored and can be retrieved. It
is also a symbol (e.g. with numerical controllers) for identifying a
function unit for which subsequent geometrical or technological
data are determined by the symbol.
Algorithms
According to DIN 19226: Algorithms are a finite series of well-de-
fined regulations. The desired output quantities are created from
permitted system input quantities. It describes how something is
to be done. A procedure must at least satisfy the following re-
quirements to be valid as an algorithm in a mathematical context.
Discreteness:
An algorithm is made up of a finite series of steps.
Determinacy: Under the same start conditions, it always creates
the same end result.
Clearness:
The series of steps is clearly defined.
Finiteness: It ends after a finite number of steps.
From a quantity theory perspective, an algorithm is clearly defined
by a set of sizes [input, intermediate and output sizes], a set of
elementary operations and also by a regulation, which specifies
when and in what sequence certain operations should be carried
out. From a functional perspective, it transfers a set of input sizes
into a set of output sizes. It can be represented in text form in a
natural or artificial formal language or using graphic representa-
tions [graph, program flow chart, structured chart, Petri Nets etc.].
ANSI
American National Standards Institute > this organization pro-
motes and manages American industrial standards.
Automation
According to Brockhaus: The application of technical means, us-
ing specific programs that (either partially or totally) do not require
human intervention to perform operations.
Automation Runtime
A uniform runtime system for all B&R automation components.
Failure
Failure according to IEC 61508: A function unit loses the ability
to perform a required function. In regards to safety-oriented sys-
tems, a distinction is made between dangerous and safe failures.
This depends on whether the status of the system failure is con-
sidered dangerous or safe. The cause of the failure may be load
related or age-related, and therefore a random failure, or related
to a flaw inherent in the system. In this case, it is known as a
systematic failure.