Rockwell Automation 1794-APBDPV1 FLEX I/O PROFIBUS Adapter User Manual - Manual (Page 84)

Publication 1794-UM064B-EN-P - May 2014
72 Connect Your Adapter to the PROFIBUS DP Network
Cabling and Equipment
Required for Line A Type Line A cabling can support baudrates as high as 1.5 Mbits/s.
Cables
You need a shielded twisted pair cable for your cabling (bus segments or drop
cables). Any line A cable available on the market can be used to connect your
adapter to a PROFIBUS network.
T-junction Connectors
You need t-junction connectors to connect your droplines to bus segments. You
can use any t-junctions available on the market.
Termination Blocks
Termination blocks are only needed if the devices on the end of the network do
not have built-in terminating resistors. If you need termination blocks, you can
use any termination blocks available on the market.
Maximum
Length
with Baud
Rate
(bits/s) of: ≤ 19.2
k
1200 m 1200 m ≤ 15 nF
93.75 k 1200 m 1200 m ≤ 3 nF
187.5 k 1000 m 600 m
≤ 1 nF
500 k 400 m 200 m
≤ 0.6 nF
1.5 M 200 m NA
≤ 0.2 nF
12 M 100 m
Where: NA = Not Applicable
(1) Measurements are the sum of all bus segments and drop cable lengths combined.
(2) If using a combination of both line types, divide the lengths shown by two.
Line Type Characteristics
Characteristic Bus Segments and Drop Cables
(1)
Line A Requirements
(2)
Line B Requirements Total Capacity of
all Drop Cables
Impedance 135…165 Ω (3-29 MHz) 100…130 Ω (f> 100 kHz)