IFM Electronic Ecomot300 AC2630, Device Manual

Page: 17 / 35

UK
Field modules DP
17
on off off DP start-up okay,
but still no Data_Exchange_
Message
Start cyclic
PROFIBUS communication
on off on Module is
exchanging data
no error
6.1.3 Error causes
Should you have any problems with the module, the status LEDs will provide
information on the probably error cause�
Avoidance of typical errors
Checking the PROFIBUS cabling
A PROFIBUS cable (or a cable segment when using a repeater) can be tested with
a few resistance measurements�
For this, the cable should be disconnected from all stations:
Measurement points Typical resistance
between "A" and "B" at the beginning of the cable approx� 110 Ω
between "A" and "B" at the end of the cable approx� 110
Ω
between "A" at the beginning and "A" at the end of the cable approx� 0
Ω
between "B" at the beginning and "B" at the end of the cable approx� 0
Ω
between shield at the beginning and shield at the end of the cable approx� 0
Ω
If these measurements are successful, the cable is error-free�
Should there be further bus errors, these are usually caused by EMC� Please also observe the instal-
lation guidelines of the PROFIBUS user organisation (www�profibus�com)�
6.2 Error diagnosis via software
In the event of an error, the modules automatically send the diagnostic data to the
DP master�
Please note, that the parameter [IP module diagnostics] of the modules with diagnostic capabilities
must be enabled�
In general, DP masters have the possibility to check by means of a flag in the PLC
whether diagnostic data have changed�
The diagnostic data can then normally be read via a function block� If more
diagnostic data apply than can be transmitted, this will be indicated in the
diagnostic data�