User Manual

Glossary
SIMATIC IPC427C
160 Operating Instructions, 04/2009, A5E02414743-01
License key
The license key represents the electronic license stamp of a license. Siemens provides the
license keys for protected software.
License key disk
The license key disk contains the authorizations or license keys required to enable protected
SIMATIC software.
Low-voltage directive
EC Product Safety Directive relating to the safety of products which are operated on low
voltage (50 VAC to 1000 VAC, 70 VDC to 1500 VDC) and not specified in other directives.
Compliance is confirmed by the CE symbol and the EC certificate of conformity.
LPT interface
The LPT interface (Centronics interface) is a parallel interface that can be used to connect a
printer.
Memory card
Memory cards in credit card format. Memory for user programs and parameters, for
example, for programmable modules and CPs.
Module
Modules are plug-in units for PLCs, programming devices or PCs. They are available as
local modules, expansion modules, interfaces or mass storage (Mass storage module).
Module retainer
The module retainer is used to fasten modules and ensure safe contact and transport.
Shocks and vibrations especially affect large, heavy modules. It is therefore recommended
to use the module retainer for this type of module. There are also short, compact and light
modules on the market. The module retainer was not designed for these modules because
the standard fastening is sufficient for them.
Motherboard
The motherboard is the core of the computer. Here, data are processed and stored, and
interfaces and device I/Os are controlled and managed.