Endress+Hauser Proline Prosonic Flow 93, Руководство по эксплуатации

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Wiring Proline Prosonic Flow 93 PROFIBUS DP/PA
58 Hauser
4 Wiring
#
Warning!
When connecting Ex-certified devices, please refer to the notes and diagrams in the Ex-specific
supplement to these Operating Instructions. Please do not hesitate to contact your Hauser
sales office if you have any questions.
!
Note!
The device does not have an internal power switch. For this reason, assign the device a switch or
power-circuit breaker which can be used to disconnect the power supply line from the power grid.
4.1 PROFIBUS cable specifications
4.1.1 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. Please 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) x segment length
!
Note!
NO_REP = maximum number of repeaters that may be switched in series depending on the
repeater in question.
Cable type A
Characteristic impedance 135 to 165
Ω
at a measuring frequency of 3 to 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 shielding
Transmission rate Line length
[kBit/s] [m] [ft]
9.6 to 93.75 1200 4000
187.5 1000 3300
500 400 1300
1500 200 650
3000 to 12 000 100 330