Siemens SIMATIC MOBY D System Manual page 345

Multi-tag capability
Multi-tag capability means that a write/read device can communicate simultaneously with
different data carriers.
Programmable logic controller (PLC)
The programmable logical controllers (PLC) of the SIMATIC S5 system consist of a central
controller, one or more CPUs, and various other modules (e.g. I/O modules).
Reader/writer
See write/read device
Readers
Readers ensure fast, secure data transfer between mobile data storage units and higher-
level systems (PLCs, PCs, etc.). The data, energy included, are transmitted inductively
across an electromagnetic alternating field or by radio. This principle enables contact-free
data transmission, ensures high industrial compatibility and works reliably in the presence of
contamination or through non-metallic materials.
RFID systems
SIMATIC RF identification systems control and optimize material flow and production
sequences. They identify reliably, quickly and economically, use non-contact data
communication technology, and store data directly on the product. They are also resistant to
contamination.
Secondary fields
The strength of the secondary fields, which exist in addition to the transmission window, is
usually lower than that of the transmission window and depends on the metallic environment.
Secondary fields should not be used in configuring.
Static mode
In static mode the transponder is positioned at a fixed distance (maximum: limit distance)
exactly above the write/read device.
Transmission distance
Distance between write/read device/antenna and transponder (mobile data storage unit)
Transmission window
Area in which reliable data exchange between transponder and write/read device is possible
due to a particular minimum field strength.
MOBY D
System Manual, 01/2010, J31069-D0147-A6-7618
Glossary
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