Table of Contents
Advertisement
PROFIBUS Power Hub Segment Coupler 3 (SK3)
Operation
Non-redundant masters do not see any effect on PA slaves from redundancy switchover. The
backup gateway takes over communication seamlessly. Both gateways participate in general
token ring operation:
Primary gateway = PA master address 1
■
Secondary gateway = PA master address 2
■
Participation in token ring operation thus allows use of handhelds for diagnostic purposes.
Note!
Information: The built-in slave must participate in cyclic data exchange.
In the flying redundancy environment all PA slaves are configured as normal non-redundant
slaves. The built-in slave can be configured as a flying redundancy slave. For additional
information, see chapter 8.
Master 1
Applications with Redundant Operation
Redundancy is available in the following cases:
Both gateways are in operation with no errors
■
Both gateways detect DP baud rates
■
No errors occurred in PA communication
■
If redundant operation is not available, this is reported back by the slave diagnostics.
Possible reasons for redundancy switchover are the following:
Hardware error in the primary gateway
■
Loss of baud rate (cable break, etc.)
■
Built-in slave drops out of the cycle (because of an unlock from the master or the
■
watchdog time has expired, etc.)
Redundancy switching in either of the following cases:
Both built-in slaves dropped out of communication and the primary BIS immediately
■
comes up on the bus again
The built-in slaves on the DP bus have changed roles
■
The primary gateway can be identified by the following LED: "Red." (redundancy) is flashing or
lights up.
Master 2*
Primary
PA Slave
Gateway
PA Slave
PA Slave
Backup
PA Slave
Gateway
*Flying Redundancy
45
Advertisement
Table of Contents
