13 PROFIBUS GATEWAY MODULE (PGM) TROUBLESHOOTING
13.1.7 PGM power failure
In the event of a PGM power failure, the PGM loses its connection with C300 and PIOMB. However, it retains
the field network configuration and the DSB configuration. When the PGM is powered on, the network-related
configuration such as the slave device configuration, Baud Rate, Slave Data Memory Offset address is retained
because of RAM retention.
The input channels are set to fail-safe values (NaN and Off for analog and digital values respectively). The
channel status is set to "Bad."
The function blocks react to the fail-safe data.
The output channels request the upstream block to go into initialization. The upstream Regulatory Control block
should realize that it is connected to an output channel and there is a loss of communication with the I/O.
The Regulatory Control block should shed the mode to the user-selected mode.
13.1.8 Removal of PGM from IOTA
When a PGM is removed from the IOTA under powered condition and re-inserted, the PGM should power up
successfully and the module state must be "RUN." Also the control strategies must work normally.
13.1.9 Mismatch of the slave device and the master addresses
The following list illustrates the behavior of the PGM during mismatch of slave device and the master address.
Slave devices with identical station address - When two slave devices with identical station address are
connected to the network, the slave device that is locked by the master first for communications continues to
operate. However, the other slave device will not be in use.
Two masters with identical station address - When two masters with identical station address are
connected to the network, the read/write operations are stopped.
13.1.10 Experion server switchover
In the event of an Experion server switchover, if the PGM is using a Flex station, the server switchover results
in a momentary loss of view. However, if the PGM is using Console station, the server switchover does not
result in loss of view or loss of control. In both scenarios, the DSB continues to update the PIOMB.