BMENOS0300 in Standalone PAC Local Rack with Two BMENOC0301/11 Modules Supporting RIO and DIO Rings

RIO Main Ring and DIO Ring

In this topology, the BMENOS0300 network option switch is used in place of a BMENOC0301/11 to reduce cost. The ports of the BMEP58•040 and the BMENOS0300 module are used as follows:

The two network ports on the CPU support an RIO main ring.
The two network ports on the BMENOS0300 switch are configured for a DIO Ring.
The service port on the BMENOS0300 module is configured as an Access port, and supports an engineering tool (for example, Control Expert) resident on a PC.

NOTE: Instead of a PC, a DIO cloud could be connected to the service port.

Standalone PAC on local rack

Ethernet main RIO ring

(e)X80 RIO drop

Ethernet DIO ring

Distributed equipment

Ethernet non-looping daisy chain

Engineering tool resident on PC

NOTE:

To achieve acceptable recovery times, limit each DIO design to a single DIO main ring without sub-rings.
RSTP limits the size of the DIO ring to a maximum of 40 switched devices, including the BMENOS0300 module.
When you set the BMENOS0300 network rotary switch to DIO Ring, configure a distributed equipment Ethernet device to be the RSTP root bridge. Refer to the topic Device Rotary Switch Positions for information about the effects of selecting DIO Ring.