Siemens SIMATIC PC 847B Operating Instructions Manual page 220

Glossary
Enhanced Write Filter (EWF)
Configurable write filter that allows you, for example, to boot Windows XP Embedded from
write-protected media (such as CD-ROM), to write protect individual partitions and adapt the
performance of the file system to your needs (when using Compact Flash cards).
ESD directive
Directive for using electrostatic sensitive components.
Ethernet
Local network (bus structure) for text and data communication with a transfer rate of
10/100/1000 Mbps.
Formatting
Basic partitioning of memory space on a magnetic data medium into tracks and segments.
Formatting deletes all data on a data medium. All data media must be formatted prior to their
first use.
Gender changer
Using the gender changer (25-pin / 25-pin), the COM1/V24/AG interface of the SIMATIC PC
family can be converted to the usual 25-pin male connector.
Hard disk drives
Hard disks represent a form of magnetic disk storage medium (Winchester drives, hard
disks) with integrated magnetic disks.
Hot swapping
The SATA interface gives the device's hard drive system hot-swap capability. Prerequisite
for this configuration is a RAID1 system with SATA RAID controller (onboard, or slot
module), and at least two SATA removable cartridges. The advantage of hot swapping is
that defective hard disks can be replaced without having to reboot the computer.
Hub
A term in network technology. In a network, a device joining communication lines at a central
location, providing a common connection to all devices on the network.
Hyper Threading
HT technology (multi-threading) enables the parallel computing of processes. HT is only
effective when all relevant system components, such as processors, operating systems and
applications are supported.
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SIMATIC Rack PC 847B
Operating Instructions, 06/2008, A5E02203168-01