Endress+Hauser Proline t-mass 65 PROFIBUS DA, Operating Instructions Manual

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Electrical connection Proline t-mass 65 PROFIBUS DP/PA
28 Hauser
5 Electrical connection
#
Warning!
When connecting Ex-certified measuring devices, see the notes and diagrams in the Ex-spe-
cific supplement to these Operating Instructions. Please do not hesitate to contact your
Hauser sales center if you have any questions.
5.1 Cable specifications
5.1.1 PROFIBUS DP cable specifications
Cable type
Two versions of the bus line are specified in IEC 61158. Cable type A can be used for all
transmission rates up to 12 Mbit/s. Refer to the table for the cable parameters:
Bus structure
Note the following points:
• The maximum line length (segment length) depends on the transmission rate.
For cable type A, the maximum line length (segment length) is as follows:
• 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:
( 1) × segment length
!
Note!
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) × 200 m = 2000 m.
Cable type A
Characteristic impedance 135 to 165

at a measuring frequency of 3 to 20 MHz
Cable capacitance < 30 pF/m
Core cross-section >0.34 mm

, corresponds to 22 AWG
Cable type Twisted in pairs, 1 × 2, 2 × 2 or 1 × 4 wire
Loop-resistance

110

/km
Signal damping Max. 9 dB over the entire length of the cable section
Shielding Copper braided shielding or braided shielding and foil shielding
Transmission rate [kBit/s] 9.6 to 93.75 187.5 500 1,500 3,000 to
12,000
Line length [m]([inch]) 1,200 (4,000) 1,000
(3,300)
400 (1,300) 200 (650) 100