
4. Troubleshooting (PROFIBUS DP)
4.2.3.5 Network Configuration and Specifications
(1)Maximum Cable Length
Check that the cables used on the network meet the following specifications.
Baud Rates | Max. Cable Length |
12 Mbps | 100 m |
6 Mbps | 100 m |
3 Mbps | 100 m |
1500 kbps | 200 m |
500 kbps | 400 m |
187.5 kbps | 1000 m |
93.75 kbps | 1200 m |
19.2 kbps | 1200 m |
9.6 kbps | 1200 m |
(2)Terminating Resistor
Ensure that two terminating resistors are connected to both ends of the network. The terminating resistor should be connected as shown below.
| VP (6) |
| 390 Ω |
Data Line B | |
| |
| 220 Ω |
Data Line A | |
| |
| 390 Ω |
| DGND (5) |
(3)Cable
The cables should meet the PROFIBUS specifications.
ItemProperty
Impedance | 135 to 165 Ω |
Capacity | < 30 pf/m |
Loop resistance | 110 Ω/km |
Wire diameter | 0.64 mm |
Core | > 0.34mm2 |
Fieldbus I/O Rev.6 | 135 |