8. Glossary
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A complete execution of the applicative program in a programmable controller.
IEC Variables created in POUs and GVLs during the applicative development, which are not addressed
directly in the memory.
Name associated with a variable or a logic that allows a brief identification of its contents.
Predetermined maximum time that a communication is completed. If exceeded retentive or diagnostic
procedures will be activated.
Element that has two stable states, alternately exchanged each activation.
It is a mark that indicates who is the master of the bus at the time.
Acronym used to indicate serial transmission.
PLC configuration or program reading.
Stands for unshielded twisted pair. Cable type formed by pairs of unshielded twisted wires. For network
applications, UTP term generally refers to the cable 100 ohms, Category 3, 4 or 5, specified by the TIA /
EIA 568-A. Normally the UTP cable has four pairs of wires twisted within the same sheath (outer
package).
Protection device against voltage surge.
Information unit composed by 16 bits.
Electronic circuit used to verify the equipment function integrity.
Physical layer for Ethernet type defined in the IEEE 1990 standard supports 802.3i baud rates of 10
Mbps over two pairs of category 3 twisted strands.