Physical Bus Characteristics And Installation Techniques For The Sinec L2 Network; Rs 485 Transmission Technology; Sinec L2 Bus Segment With Rs 485 Technology - Siemens SIMATIC S5 Manual

S5-95U, SINEC L2
1.6 Physical Bus Characteristics and Installation Techniques for the
SINEC L2 Network
You can connect the S5-95U programmable controllers to SINEC L2 networks using two different
types of transmission technologies:
•

RS 485 transmission technology

(advantages: interference-proof due to difference signals, and economical)
• Fiber optic transmission technology
(advantages: no EMC problems, electrical isolation between the stations, larger network
expansion capability as with the RS 485)
Refer to the SINEC L2/L2FO Network Manual for detailed information about transmission
technologies.
1.6.1

RS 485 Transmission Technology

Physical bus characteristics and related distances
A SINEC L2 network consists of one or more bus segments.
Figure 1-14 shows a SINEC L2 segment with RS 485 technology.
SINEC L2 bus connector
(terminating resistor
connected)
Figure 1-14. SINEC L2 Bus Segment with RS 485 Technology
You can link the bus segments by repeaters. Figure 1-15 shows a SINEC L2 network with RS 485
technology. The terminology is explained later on.
EWA 4NEB 812 6112-02
SINEC L2 bus connector
(terminating resistor disconnected)
Data Rate Distance
9.6 Kbits/s 1.2 km
19.2 Kbits/s 1.2 km
93.75 Kbits/s 1.2 km
187.5 Kbits/s 1.0 km
500 Kbits/s 0.4 km
1500 Kbits/s 0.2 km
System Description
Bus cable
SINEC L2
station
1-21