Endress+Hauser Proline Promass 83 - 4 Wiring; PROFIBUS Cable Specifications; PROFIBUS DP Cable Specifications

Wiring Proline Promass 83 PROFIBUS DP/PA
26 Endress+Hauser
4 Wiring
#
Warning!
When connecting Ex-certified devices, see the notes and diagrams in the Ex-specific supplement to
these Operating Instructions. Please do not hesitate to contact your Endress+Hauser sales office if
you have any questions.
4.1 PROFIBUS cable specifications
4.1.1 PROFIBUS DP cable specifications
Two versions of the bus line are specified in IEC61158. Cable type A can be used for all transmission
rates up to 12 Mbit/s. Please refer to the table for the cable parameters:
Bus structure
Note the following points:
• The maximum line length (segment length) of a PROFIBUS DP system depends on the
transmission rate. For PROFIBUS RS485 cable type A, it is:
• A maximum of 32 users are permitted per segment.
• Each segment is terminated at either end with a terminating resistor.
• The bus length or the number of users can be increased by introducing a repeater.
• The first and last segment can comprise max. 31 devices. The segments between the repeaters
can comprise max. 30 stations.
• The maximum distance between two bus users can be calculated as follows:
(NO_REP + 1) x segment length
NO_REP = maximum number of repeaters that may be switched in series depending on the
repeater in question.
Example:
In accordance with manufacturer specifications, 9 repeaters can be switched in series when using
a standard line.
The maximum distance between two bus users at a transmission rate of 1.5 MBit/s can be
calculated as follows: (9 + 1) x 200 m = 2000 m
Cable type A
Characteristic impedance 135...165 Ω at a measuring frequency of 3...20 MHz
Cable capacitance < 30 pF/m
Core cross-section >0.34 mm
2
, corresponds to AWG 22
Cable type Twisted in pairs, 1 x 2, 2 x 2 or 1 x 4 wire
Loop-resistance 110 Ω/km
Signal damping Max. 9 dB over the entire length of the cable section
Shielding Copper braided shielding or braided shielding and foil screening
Transmission rate [kBit/s] 9.6...93.75 187.5 500 1500 300...12000
Line length [m] 1200 1000 400 200 100