Siemens S7-400 Installation Manual page 296

Glossary
Data, Static
Static data are data which are used only within a function block. These data are
stored in an instance data block belonging to the function block. The data stored in
the instance data block are retained until the next function block call.
Data, Temporary
Temporary data are local data of a block that are stored in the L stack during
processing of the block and that are not retained after processing.
Default Setting
A default setting is an expedient basic setting which is always used when no other
value is preset by a parameter.
Diagnostics
³ System Diagnostics
Diagnostic Buffer
The diagnostic buffer is a retentive area of memory within the S7-400 CPU which
stores the diagnostic events in the order they occurred.
Diagnostic Interrupt
Modules with diagnostics capability signal system errors to the S7-400 CPU by
means of diagnostic interrupts.
E
Electromagnetic Compatibility (EMC)
Electromagnetic compatibility is understood to mean the capability of electrical
apparatus to operate without faults in a given environment, without affecting that
environment in an unacceptable manner.
Equipotential Bonding
An electrical connection (equipotential bonding conductor) that ties the exposed
conductive parts of an item of electrical equipment and extraneous conductive
parts to the same, or approximately the same, potential in order to prevent
disturbing or dangerous voltages between these parts.
Glossary-4
S7-400 and M7-400 Programmable Controllers Hardware and Installation
A5E00069481-04