IDENT-I • IRI-KHD2-4HB5, IRI-KHA6-4HB5
Installation
Subject to reasonable modifications due to technical advances.
Copyright Fuchs, Printed in Germany
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
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5.4.2
Read head/cable lengths
The connecting cables to the read heads must be shielded. The cross section of the
cables must be at least 0.14 mm
2
.
The screen of the read head lead is connected on both sides to earth (PE) with low
resistence and low induction. For that the attached terminal block can be used (see
figure 5.5.). Please make sure that the screen is kept as small as possible.
Figure 5.5
Terminal block with connecting cables
Read head cable lengths up to 50 m or 100 m are possible if the following conditions
are satisfied.
up to 50 m read head cable:
cross sectional area of at least 4 x 0.25 mm
2
maximum resistance 78 Ohm/km
maximum capacitance 90 pF/m
(e.g. LIYC11C, Mukkenhaut & Nusselt MUNFLEX
C11Y)
up to 100 m read head cable: cross sectional area of at least 4 x 0.5 mm
2
maximum resistance 37 Ohm/km
maximum capacitance 90 pF/m
With a cable length of 100 m, a series resistor of 82 Ohm must be fitted
in the cable connected to the 'Reset' terminal of the read heads.
Since more EM interference can result with longer cable lengths, the
maximum cable lengths given above might not be possible for some
applications.