Emerson PACSystems RX3i, User Manual

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RSTI-EP PROFINET I/O Controller User Manual Appendix A
GFK-2571R May 2021
PROFINET IO Performance Examples 151
Appendix A: PROFINET IO Performance
Examples
Note
: The configurations and performance numbers shown here are examples; Actual
performance timings will vary depending on your exact configuration and network
setup.
This section presents various PROFINET IO systems and their measured I/O performance for
a simple Discrete IO loopback in an RX3i IO Device and in a VersaMax IO-Device. As these
systems are not identical in their configuration or setup, additional details of each system
configuration are provided in the sections below.
The IO Loopback measurements were done by wiring the outputs of a discrete output
module directly to the inputs of a discrete input module and using Ladder Logic to measure
the time difference between setting the outputs and reading the same data on the
corresponding inputs. PAC Machine Edition was attached to the RX3i during testing. The
average, minimum, and maximum loopback times were captured from a 4-hour sample
period. In addition, since the CPU sweep time is a primary factor in the accuracy and
precision of the IO Loopback times recorded, the average and maximum CPU sweep times
for each system are given.
Note:
CPU Sweep time variations between systems are not completely a function of varying
PROFINET IO. It was also influenced by variations in logic executed and main rack
configurations.
A-1 Systems with RX3i PNS
RX3i System Performance Summary
System
Configuratio
n
Total # of
PROFINET I/O
Devices/Modules
20
Total Amount
PROFINET I/0
Discrete pts./
Analog Chan.
RX3i CPU
Sweep Time
(ms)
Average
(Max)
16-pt.
Discrete I/O
Loopback
Time (ms)
Average
(Min, Max)
1 ms PROFINET Update Rate
A.2.1 - Multi-
Device w/MRP
8/33 x 12-slot racks 176/16 4.1 (6.7) 12 (7, 20)
16 ms PROFINET Update Rate
20 Number of modules includes I/O modules only; does not include head-ends or power-supplies.