Dimensioning Of A Field Bus Segment In Accordance With Iec 61158-2 - Pepperl+Fuchs KLD2-PR-Ex1.IEC. Manual

Power repeater / power supply according to IEC 61158-2
Modulation cur-
rent
on field side
max. number of
field bus instru-
a
ments
max. line length
min. line length
a.The actual number of field devices on a bus segment depends on the actual current consumption of the slaves. The specified numbe r of field devices is only reached if
the current consumption for each station is 10 mA.
b.The actual line length depends among other things on the cable that is used and the number and distribution of slaves.
c.For max. output current and cable type A [0.8 mm² (18 AWG)]
If a Power Repeater with an intrinsically safe interface is used, the
requirements of EN 50020 "Explosion Protection through Intrinsic
Safety" and the PTB report PTB-W-53 (FISCO model) or the Entity
model must be observed.
Power repeater KLD2-PR-Ex1.IEC is certified according to Entity and
FISCO modelThe KLD2-PR-Ex1.IEC1 power repeater is certified
according to the FISCO model field devices that are certified for the
Entity model must not be connected to the KLD2-PR-Ex1.IEC1.
For more information on the topic of explosion protection through intrinsic safety,
please refer to the Pepperl+Fuchs manual on explosion protection Part. No. 21417 or
the video Explosion Protection of Electrical Systems:

5.1.1 Dimensioning of a field bus segment in accordance with IEC 61158-2

A power repeater opens a new PROFIBUS PA or H1 bus segment. The following sec-
tion illustrates how a field bus segment of this type should be dimensioned.
The following section assumes that a cable with the following characteristic values is
in use:
Conductor cross-section (nominal)
Loop resistor (direct current)
Wave resistance at 31.25 kHz
Wave attenuation at 39 kHz
Capacitive asymmetry
Group runtime distortion (7.9 ... 39) kHz
Covering level of the shield
The cable parameters that are specified are cable type A of the PROFIBUS PA Com-
Subject to reasonable modifications due to technical advances.
Pepperl+Fuchs Group • Tel.: Germany (06 21) 7 76-0 • USA (330) 4 25 35 55 • Singapore 7 79 90 91 • Internet http://www.pepperl-fuchs.com
KLD2-PR(2)-
Ex1.IEC
+10 mA
6
b 1000 m
c 519 m
Cable structure
FOUNDATION FieldbusGeneral
KLD2-PR(2)- KLD2-PR-
Ex1.IEC1 NI1.IEC
+10 mA +10 mA
10
1000 m 1900 m
860 m 348 m
twisted wire pair, shielded
0.8 mm² (AWG 18)
100 Ω + 20 %
Copyright Pepperl+Fuchs, Printed in Germany
KLD2-PR-
1.IEC
+10 mA
21 32
1900 m
852 m
44 Ω/km
3 dB/km
2 nF/km
1.7 µs
90%
13