Network Errors - Omron SYSMAC CS Series Operation Manual

Troubleshooting Using LED Indicators
7-2-5

Network Errors

Network Errors
BST COMM BF
Not lit Not lit Not lit
Lit
Lit Not lit
Lit
Network errors are errors which occur when attempting to startup a network,
i.e. the PROFIBUS Master Unit has been switched to CLEAR or OPERATE
mode. The Unit will parameterize the slave devices and start data exchange.
An error in this process can be determined by examining the BST, COMM and
BF LED indicators.
The error determination procedure uses the table below. To determine the
error
• First find the status of the BST LED indicator (left column).
• Move one column to the right and find the COMM LED indicator status.
• Move one column to the right and find the BF LED indicator status.
The probable error causes are then listed to the right of the third column.
Probable cause
The PROFIBUS Master Unit is in OFFLINE
or STOP mode. No communication over
the network.
A hardware error has occurred in the
PROFIBUS interface of the Unit, or a mas-
ter device has been detected beyond the
Highest Station Address. The Unit has
switched to OFFLINE.
This indicates faulty wiring, broken mes-
sage, short-circuits, faulty bus timings, or
an active device has been detected beyond
the Highest Station Address setting (HSA).
A protocol error has occurred in the PROFI-
BUS interface of the Unit, the Unit has
switched to OFFLINE.
This indicates lost tokens.
A Double-Address error has occurred on
the network, i.e. there is a second master
device with the same PROFIBUS address
on the network. the Unit has switched to
OFFLINE.
Not a valid combination.
Not a valid combination.
Correction
Switch the Unit to either CLEAR or OPER-
ATE mode.
• Check the network wiring, and make
sure it is correct (not too long, long stub
lines, etc.)
• Check for short-circuits.
• Check the bus timing set in CX-Profibus.
• Check the HSA setting in the DTM's Bus
Parameter tab. Set it to the highest mas-
ter address which is on the network.
• Check if any other faulty devices are on
the same network.
• Switch the Unit to CLEAR / OPERATE
mode again.
• Check the network wiring, and other
master devices on the network. Make
sure they are all correct.
• Check if any other faulty devices are on
the same network.
• Switch the Unit to CLEAR / OPERATE
mode again.
• Check the master devices on the net-
work. Make sure they all have unique
network addresses.
• After correction, switch the Unit to
CLEAR / OPERATE mode again.
Section 7-2
207