Emerson PACSystems RSTi-EP - Hot Standby CPU Redundancy I;O Parameters (EPXPNS101)

User Manual Section 4
GFK-2958L May 2021
Detailed Descriptions of the Fieldbus Network Adapters 75
4.2.6 Hot Standby CPU Redundancy I/O Parameters
(EPXPNS101)
The “Redundancy” tab selects if the PNS is redundantly controlled. The RSTi-EP PNS
(EPXPNS101) supports PROFINET System Redundancy when it is configured in an HSB CPU
Redundancy system. The Programmer automatically selects redundant control if user sets
the “Redundancy” parameter to “HSB CPU Redundancy”.
Figure 27
When the PNS is not configured in an HSB CPU Redundancy system, the Programmer
automatically selects simplex operation (non- redundant control) by setting the
“Redundancy Mode” parameter to “None”.
If desired, the user may configure a redundancy-capable PNS within an HSB CPU
Redundancy system for simplex operation (non-redundant control) by changing the
“Redundancy Mode” parameter on the Redundancy tab form “HSB CPU Redundancy” to
“None”.
Refer to the PACSystems Hot Standby CPU Redundancy User’’ Manual, GFK-2308G or later,
for detailed information on setting up a Hot Standby Redundancy system.
Transfer List
All redundantly controlled I/O must be included in the CPU’’ I/O transfer list. Note that once
the HSB CPU Redundancy Mode is set, PAC Machine Edition automatically expands the
Primary CPU’’ input transfer list to include all redundantly controlled PROFINET inputs as
reference addresses are being assigned. PAC Machine Edition also automatically expands
the Primary CPU’’ output transfer list to include all redundantly controlled PROFINET
outputs.
The configuration should be stored to both the Primary and Secondary racks before
attempting to control any I/O in the RSTi-EP PNS.
Changing a Redundant PNS Configuration
Changes to the device’’ configuration on either the Primary while the Secondary is running
or the Secondary while the Primary is running will cause a Loss of Device I/O fault on the
controller that is being updated. The controller with the changed configuration will be
prevented from re-connecting as long as a non-matching connection exists with the device
from any controller.