Troubleshooting Profibus Communication - Omron GRT1 - 27-11-2006 Operation Manual

Other Errors
4-3-2

Troubleshooting Profibus Communication

Problem
PROFIBUS DP Master Unit
is configured, but only the
SmartSlice I/O Unit is not
exchanging data.
PROFIBUS DP Master Unit
is configured, but none of
the slaves are exchanging
data.
Probable cause
The PROFIBUS configuration of the master
for the Unit is not correct.
The SmartSlice bus has one of the following
problems at start-up:
• One or more SmartSlice Units are missing.
• Disconnected turn-back cable.
The PROFIBUS configuration for the Unit
can not be compared with the actual configu-
ration. The SmartSlice I/O Units PROFIBUS
Diagnostics indicates that the Unit is in state
Not Ready.
No power is supplied to the system.
• All LED indicators on the system are OFF.
The PROFIBUS DP Master Unit is in either
OFF-LINE or STOP mode.
• The Master's BST LED indicator is OFF
The Master Unit may have been config-
ured to maintain its current mode (last
mode was OFF-LINE, during download).
• The Master's and BF the Unit's LED indi-
cator are ON: A PROFIBUS interface error
has occurred: see Master Status 2 error
flags (Master CIO Word n+6, bit 00 ~ 03,
see Note) for details.
Network cabling is not correct.
• Master BF LED and/or Unit BF LED indi-
cator is ON.
• Master Status 2 error flag may provide
more information (Master CIO Word n+6,
bit 00 ~ 03, see Note).
• Master CIO Words n+9 to n+16 show
which slaves have problems.
Correction
• Verify that the first selected I/O module is
the "COM status" Module (see Note).
• The SmartSlice I/O Unit supports Profibus
DPV1 Class 2, not DPV1 Class 1. The
slave configuration must not have the
DPV1 class 1 option enabled (hence the
DPV1 tab of the Generic Slave DTM).
Always disable the DPV1 class 1 setting
for the Unit.
• Check the configuration and the parame-
ter data of the slave.
• Verify that the selected configuration
matches the physical slice configuration
attached to the PROFIBUS Communica-
tion Unit.
• Verify the Profibus allocation of the Smart-
Slice I/O Unit is according the description.
Check the Profibus Diagnostics. refer to
Appendix B Slave Diagnostics Message.
Connect the Smart Slice Units and the cables
properly and turn the power ON again.
• Verify that power is supplied to the sys-
tem.
Determine the mode of the Master Unit:
Check the Master Status 1 Word (Master
CIO Word n+5, bit 00 to bit 03, see Note). If
Unit is in OFF-LINE or STOP mode:
• Verify that the master does not use the
same address as another Master Unit on
the network. Otherwise, correct the Master
Unit's PROFIBUS address.
• Set CLEAR or OPERATE switch in Master
CIO Word n (see Note).
• Change the configuration to set the Master
Unit OPERATE mode when switching the
PLC to RUN/MONITOR mode (see Master
DTM, Master Setup Tab). Download the
configuration, and switch the PLC to RUN/
MONITOR mode.
Verify that the network installation is correct:
• Verify that all slaves are powered up and
functioning correctly.
• Verify that all slave devices are correctly
connected to the network.
• Verify that any repeaters used are func-
tioning correctly.
• Check the cable length versus the
selected baud rate.
• Verify that used stubs are not too long.
• Verify that termination (resistors and
inductors) are properly set and used.
Section 4-3
65