External Switch Vlan Priority Settings - Emerson PACSystems RX3i User Manual

User Manual
GFK-2883F
3.4

External Switch VLAN Priority Settings

If a system includes external switches, these switches must be configured to match the
VLAN Priority groupings listed below for the RX3i CEP.
The PROFINET-I/O specification indicates the VLAN priorities for each type of Ethernet traffic
that originates from a PROFINET IO-Device. VLAN priorities range from 0 to 7, with 7 being
the highest.
The switch on an RX3i CEP Carrier supports just two traffic classes, giving two levels of
preference. Incoming traffic without a VLAN priority is assigned to the lowest priority traffic
class. The following table lists the VLAN priorities, and their corresponding priorities in the
RX3i CEP:
Table 4
VLAN Priority
7, 6, 5
4, 3, 2, 1, 0
An external switch that supports only two traffic queues must be configured like the RX3i
CEP Carrier, as listed in the table above. An external switch that does not support a VLAN
priority mapping that exactly matches the mapping used by the RX3i CEP Carrier can be
used if it can be configured with the following relationships between VLAN priorities:
•
•
•
If the external switch does not allow VLAN priority 4 to be treated differently from priority 5,
it should be used only if no device on the network will generate VLAN Priority 4 Ethernet
Traffic.
Installation & Mounting
1. Check the PWR LEDs on the RX3i CEP carrier to be sure that the input source
that is not being removed is currently supplying power.
2. Remove power from the power supply that is to be removed.
3. Wait until the PWR LED for the power supply that is being removed goes off.
4. Remove and replace the power supply that is powered off.
5. Apply power to the power supply and confirm that the corresponding LED is on.
Preference / Traffic Class
Real-time (High Priority).
This includes the following Ethernet traffic:
PTCP, MRP, MRRT, RT_CLASS_2, RT_CLASS_1, RT_CLASS_UDP, High Priority
RTA_CLASS_1, High Priority RTA_CLASS_UDP, Low Priority RTA_CLASS_1, Low
Priority RTA_CLASS_UDP.
Non-real-time (Lower Priority).
This includes the following Ethernet traffic:
IP, DCP, and other untagged traffic.
VLAN Priority 7 is forwarded with at least as much preference as VLAN Priority 6.
VLAN Priority 6 is forwarded with at least as much preference as VLAN Priority 5.
VLAN Priority 5 is forwarded with more preference than VLAN Priorities 0, 1, 2, 3 and
4.
Chapter 3
Sep 2019
26