Siemens SIMATIC NET PROFIBUS Simatic NET PC modules, Slave, Softnet for Profibus, Standard rail

Glossary

SIMATIC NET PC modules

SIMATIC NET PC modules are modules for coupling the PC to bus systems, such as PROFIBUS or Industrial Ethernet.

Slave

A slave can only exchange data with a ³ master after it has been request to send data by the master.

Slaves include, for example, all DP slaves such as ET 200S, ET 200X, etc.

SOFTNET for PROFIBUS

SOFTNET for PROFIBUS is the protocol software for the SIMATIC NET PC mo- dules CP 5511 and CP 5611.

Standard rail

Metal rail standardized in compliance with EN 50 022.

The standard rail is used for the snap-on installation of network components such as OLMs, repeaters etc.

Suppressor

Component for reducing induced voltages. Induced voltages occur when circuits with inductances are turned off.

Surge arresters

are used to limit overvoltages from remote strikes or from induction effects (for example switching in power circuits). Surge arresters (in contrast to lightning ar- resters) divert currents with a significantly lower peak value, discharges and spe- cific energies.

Terminating resistor

A resistor to terminate the LAN cable; terminating resistors are always necessary at the ends of the cable or segment.

In SIMATIC NET PROFIBUS, terminating resistors are activated or deactivated in the ³ bus connector or bus terminal or are installed as ³ terminators.

Terminator

A ³ terminating resistor in bus segments at transmission rates of 9.6 Kbps to 12 Mbps; the power supply is separate from the bus nodes.

Token

is a frame that represents the right to transmit in a network. It signals the two states ”occupied” or ”free”. The token is passed from master to master.

Glossary-6	PROFIBUS Networks SIMATIC NET
	6GK1970-5CA20-0AA1 Release 2 05/2000