ProSoft Technology 3170-PDP - Manual (Page 45)

Connect the Adapter to the PROFIBUS DP Network 3170-PDP ♦ FLEX Platform
FLEX I/O™ PROFIBUS Adapter
ProSoft Technology, Inc. Page 45 of 152
August 23, 2007
4 Connect the Adapter to the PROFIBUS DP
Network
In This Chapter
¾ The DP Physical Layer........................................................... 45
¾ Cabling and Equipment Required for Line A Type ................. 46
¾ Cabling and Equipment Required for Line B Type ................. 47
¾ Connect the Adapter to the Network ...................................... 48
¾ Terminate the Network........................................................... 49
4.1 The DP Physical Layer
The PROFIBUS network media is a balanced transmission line corresponding to
the standard EIA RS-485, terminated at both ends. Both line A and line B types
are available, depending on your system requirements.
Specifications and guidelines for DP media:
ƒ
linear bus, terminated at both ends
ƒ drop cables (preferably no longer than .30m), no branches
ƒ shielded twisted pair
ƒ max. line length between 100 and 1200m (depending on baudrate and cable
type)
ƒ number of stations: 32
ƒ DP baudrates 3, 6 and 12 M bit/s
Use the following table to determine what line type will best meet your needs.
Characteristic Bus Segments and Drop Cables
Line A Requirements Line B Requirements Total Capacity of
all Drop Cables
Impedance 135-165 W (3 to 29
MHz) 100 to 130 W (fu100
kHz)
Capacity t30 pF/m t60 pF/m
Resistance t110 W/km -
Wire Gauge u0.64 mm u0.53 mm
Conductor Area u0.34 mm2 u0.22 mm2