Chapter 13 - Tips and tricks for cable testing
48
PROFIBUS Tester BC-700-PB - User Manual
13.2
List of fault indications and remedial measures
The classifying text messages in the graphical user interface of PROFIBUS Tester 5
which describe the cabling errors are kept concisely. The table below lists possible
cabling error messages and provides a detailed description of the discovered fault
indications. The column on the right contains "remedial measures" and further starting
points in order to correctly interpret and to repair the indicated fault.
The PROFIBUS Tester 5 uses amongst other methods impulse reflectometry for
assessing the cabling and classifying and locating errors on the cable. Multiple cable
errors, which exist simultaneously on the cable may result in an imprecise cable test
result. Please bear in mind, the more the corrective repair of the cable is proceeding, the
more precise the cable test results in the corresponding PROFIBUS cable segment will
be.
Electromagnetic interferences may influence PROFIBUS cable testing in a negative
manner because cable conductors may act like an antenna. Please bear this in mind
during cable testing and take care of proper functional earthing of your plant respectively.
Existing high frequency noise voltage may negatively influence the PROFIBUS Tester 5 if
operated by means of the external power supply. We recommend operating on the
PROFIBUS-Tester 5 by means of the built-in battery under the above mentioned prevailing
conditions.
Cable testing error
message from
graphical user
interface of
PROFIBUS-Tester 5
Remedial measures - starting points for correctly
interpreting and repairing the indicated fault
Break on line A
The green signal line of the PROFIBUS-cable is broken. Please
search for damage on the cable in the vicinity of the indicated
error location. Possibly the error could come from a fatigue
breakage or a faultily assembled PROFIBUS-connector. The
green signal line typically is connected to Pin 8 of the
PROFIBUS Sub-D type connector.
Break on line B
The red signal line of the PROFIBUS-cable is broken. Please
search for damage on the cable in the vicinity of the indicated
error location. Possibly the error could come from a fatigue
breakage or a faultily assembled PROFIBUS-connector. The
red signal line typically is connected to Pin 3 of the PROFIBUS
Sub-D type connector.
Break on shield
The shielding conductor is broken in the tested cable segment.
Alternatively electromagnetic shielding is not applied for in a
continuous manner. Please search for damage on the cable in
the vicinity of the indicated error location. Possibly the error
could come from a fatigue breakage or a faultily assembled
PROFIBUS-connector.
In rare cases electromagnetic shielding may be disrupted
intentionally in order to avoid electromagnetic interferences.
Please check this issue with the planning personnel of the
PROFIBUS-facility.