Active Components for RS-485 Networks
5-8
PROFIBUS Networks SIMATIC NET
6GK1970-5CA20-0AA1 Release 2 05/2000
Segments 1 and 2 Connected Through
Figure 5-5 shows the connection between two segments via an RS-485 repeater
with each LAN cable connected through:
R
Segment 1
Segment 2
Terminating resistor
off!
Terminating resistor
Bus segment 1
off!
Terminating resistor
Bus segment 2
off!
Terminating resistor
Bus segment 2
off!
Segment 1
Segment 2
Figure 5-5 Connecting Two Bus Segments to the RS-485 Repeater
Note
If you turn off the power supply of a complete segment, the terminating resistors of
the connected nodes are also without power supply. This can lead to disruptions or
undefined signal states in this segment that are not recognized by the repeater
and can then lead to problems in the other segment.
Whenever possible, we recommend the following procedure:
S
Alternative 1:
Disconnect the two segments before turning off the power supply using switch
5 (Table “Description and Functions of the RS-485 Repeater”) on the repeater
(set to “OFF”).
S
Alternative 2:
Connect the repeater to the power supply of the segment to be turned off so
that the repeater is also turned off. In this case, make sure that the repeater is
not at the end of the previous segment, since the repeater is then the
terminating resistor which has no effect if there is no power supply. If this
solution is required, use a PROFIBUS terminator with a permanent power
supply after the repeater.
S
Alternative 3:
If you want the repeater to retain its power supply, use PROFIBUS terminators
to terminate the segment you want to turn off since these also require a
permanent power supply. You require one terminator if the bus segment to be
turned off ends at the repeater, otherwise you require two terminators.
Содержание SIMATIC NET PROFIBUS
Страница 10: ...Contents viii PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...
Страница 11: ...PROFIBUS NETWORKS 1 ...
Страница 26: ...PROFIBUS NETWORKS 1 16 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...
Страница 167: ...5 1 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 Active Components for RS 485 Networks 5 ...
Страница 184: ...Active Components for RS 485 Networks 5 18 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...
Страница 185: ...6 1 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 Passive Components for PROFIBUS PA 6 ...
Страница 197: ...7 1 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 Passive Components for Electrical Networks 7 ...
Страница 228: ...Passive Components for Electrical Networks 7 32 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...
Страница 229: ...8 1 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 Active Components for Optical Networks 8 ...
Страница 236: ...Active Components for Optical Networks 8 8 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...
Страница 237: ...9 1 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 Active Components for Wireless Networks 9 ...
Страница 240: ...Active Components for Wireless Networks 9 4 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...
Страница 241: ...A 1 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 Testing PROFIBUS A ...
Страница 254: ...Testing PROFIBUS A 14 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...
Страница 263: ...C 1 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 Installing LAN Cables C ...
Страница 288: ...Installing LAN Cables C 26 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...
Страница 290: ...Installation Instructions for SIMATIC NET D 2 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...
Страница 325: ...F 1 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 Dimension Drawings F ...
Страница 338: ...Dimension Drawings F 14 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...
Страница 339: ...G 1 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 Operating Instructions ILM OLM OBT G ...
Страница 340: ...Operating Instructions ILM OLM OBT G 2 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...
Страница 396: ...Infrared Link Modul ILM 6ZB530 3AC30 0BA1 54 Copyright by Siemens ...
Страница 434: ......
Страница 438: ...Contents ii PROFIBUS Optical Bus Terminal OBT C79000 G8976 C122 02 Contents ...
Страница 442: ...The SIMATIC NET PROFIBUS OBT Product 2 2 PROFIBUS Optical Bus Terminal OBT C79000 G8976 C122 02 ...
Страница 450: ...Network Topology 4 4 PROFIBUS Optical Bus Terminal OBT C79000 G8976 C122 02 ...
Страница 458: ...Installation and Startup 5 8 PROFIBUS Optical Bus Terminal OBT C79000 G8976 C122 02 ...
Страница 460: ...Troubleshooting 6 2 PROFIBUS Optical Bus Terminal OBT C79000 G8976 C122 02 ...
Страница 464: ...Technical Specifications 7 4 PROFIBUS Optical Bus Terminal OBT C79000 G8976 C122 02 ...
Страница 468: ...References 9 2 PROFIBUS Optical Bus Terminal OBT C79000 G8976 C122 02 ...
Страница 470: ...Abbreviations 10 2 PROFIBUS Optical Bus Terminal OBT C79000 G8976 C122 02 ...
Страница 478: ...References I 4 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...
Страница 488: ...Glossary Glossary 8 PROFIBUS Networks SIMATIC NET 6GK1970 5CA20 0AA1 Release 2 05 2000 ...