Cable Type; Bus Connection; Profibus Dp Architecture - Bernard Controls INTEGRAL+ Manual Del Usario

4 CABLE TYPE

Use exclusively special Profibus cable conform to the EN 50170-2 standard and of type A.
Example of an armoured cable and an aluminium screening, 1 pair of wires, 22awg : BELDEN ref 3079ALS
(www.belden.com)
Fieldbus wire has to be separated from the other cables with a distance of at least 20cm. It will use a
specific cable path and be connected to the earth.
It is also necessary to check that all actuators are at the same earth electric potential.

5 BUS CONNECTION

Junction box Terminals :
A, B : Profibus fieldbus.
S : Shield.
Single line
Profibus line

6 PROFIBUS DP ARCHITECTURE

In the case of a single Profibus line, the DCS (Digital Control System) and actuators are connected in serial
by one cable (a pair of wires).
A1 B1 S A1 B1 S
Connection can be done purely in serial or with some ramifications (see graph below).
Maximum line length is 1200m (3600ft). Maximum number of actuators by line is 31.
Maximum line length is reduced according to the communication speed :
Transmission baud rate < 93.75 kBit/s
Maximum line length 1200m
An end of line resistor has to be connected at each end of line actuator (for set-up see § 3.2).
Repeaters
Adding repeater modules allows to increase both the number of actuator on the line and total line length.
Repeaters exist in single or redundant configurations.
Each repeater uses one connection address (therefore this limits the number of actuators by line
segment to 30 units) and allows to lengthen the line by 1000m.
According to the type of repeater used, it is possible to use as many as 9 repeaters on a same line.
Maximum distance between the DCS and the more distant actuator is 10km.
Addressing capacity of the INTEGRALBUS board allows to connect up to 99 actuators on a same line.
The important advantage of the repeater compared to other repeater-free technologies is to keep the
communication speed unaffected and therefore to get a very short response time.
8
Redundant line (option)
Profibus line to the next actuator
A2 B2 S A2 B2 S
187.5 kBit/s 500 kBit/s 1,5 MBit/s
1000m 400m 200m
Single line
DCS
Redundant line
(option)
Segment 1 : 1000m
30 actuators
Repeaters can also be used to get additional fieldbus lines at a low cost if placed at the DCS output (see
graph below).
Each line is independent from the others and therefore a problem on a line does not affect the other.
Single line
Redundant line
(option)
DCS
Single line
Redundant line
(option)
BERNARD CONTROLS can supply single or redundant, weatherproof or explosionproof, repeaters.
Single or redundant
power supply
Repeater
Segment 2 : 1000m
30 actuators
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