Key Points when Planning a Topology

Consider these key points when you choose an M580 network topology:

  • distance between two contiguous drops (and the potential need for DRSs or BMXNRP020• fiber converter modules and fiber cable on the main ring)

  • ring or star network topology (A DIO cloud with distributed equipment in a star topology can communicate with an M580 network.)

  • local rack configuration

  • distributed equipment requirements

  • isolation requirements (e.g., if the local rack and the drops are on different grounding systems)

  • redundancy requirements for the main ring / sub-ring connections

These points are discussed in the following paragraphs.

Distance Between Two Drops

The distance between two drops determines the choice of physical layer.

If you are using copper cable, the maximum distance between two contiguous drops is 100 m. If the drops are more than 100 m apart, use 1 or more BMXNRP020• fiber converter modules to convert copper cable to fiber. A fiber cable can run as long as 15 km (for single-mode fiber).

If Distance Between Two Remote Drops is Less than 100 m...

A copper Ethernet network provides a valid solution:

Note: The solid line represents copper wire.

1 CPU with Ethernet I/O scanner service on the local rack

2 BMXNRP020• fiber converter module

3 BMENOC0321 module on the local rack, providing transparency between the device network and the control network

4 main ring

5 RIO drop (including a BM•CRA312•0 X80 EIO adapter module) on the main ring

If Distance Between Two Remote Drops is More than 100 m...

Use BMXNRP020• fiber converter modules to increase the distance between two contiguous RIO modules, including the distance between the CPU and an RIO drop. To connect the fiber to the copper cables, insert a BMXNRP020• module at each end of the fiber link. Thus, two BMXNRP020• modules establish a single fiber link:

1 CPU with Ethernet I/O scanner service on the local rack

2 BMXNRP020• fiber converter module on the local rack connected to an RIO drop on the main ring via fiber cable

3 (dashed line): fiber portion of the main ring

4 (solid line): copper portion of the main ring

5 BMXNRP020• module on an RIO drop connected to the main ring via fiber cable

6 BMXNRP020• module on an RIO drop connected to the main ring via copper and fiber cable

NOTE:

  • Use multi-mode fiber to connect the BMXNRP020• module to the main ring if the distance between the local rack and the RIO drop is less than 2 km.

  • You cannot use BMXNRP020• modules to connect RIO or DIO sub-rings to the main ring.

Using Fiber Converter Modules

Install fiber converter modules to extend the distance between the local rack and the first RIO drop on the main ring:

Step

Action

1

Install a BMXNRP020• fiber converter module on a local rack.

2

Connect the BMXNRP020• module on the local rack via copper cable to the CPU.

3

Install a BMXNRP020• module on the first RIO drop on the main ring.

4

Connect the fiber cable between the BMXNRP020• module on the local rack and the BMXNRP020• module at the RIO drop. The BMXNRP020• module uses small form-factor plugs (SFPs) (transceivers) for the fiber ports. Choose single-mode or multi-mode SFPs.

  • Use multi-mode fiber and a (BMXNRP0200) module to connect the BMXNRP020• module to the main ring if the distance between the BMXNRP020• and the next Ethernet RIO drop is less than 2 km.

  • Use the single-mode fiber module (BMXNRP0201) to connect the BMXNRP020• module to the main ring if the distance between the BMXNRP020• and the next Ethernet RIO drop is between 2 km and 15 km.

5

Interlink the two copper ports of the BMXNRP020• module with the two Ethernet ports of the BM•CRA312•0 X80 EIO adapter module on the RIO drop.

6

To extend the distance between other RIO drops on the main ring, connect the BMXNRP020• module on an RIO drop to a BMXNRP020• module on the next drop. Then, follow the above step.

Close the ring:

Step

Action

1

Interlink a copper port on the BMXNRP020• module with an Ethernet port on the BM•CRA312•0 X80 EIO adapter module on the last RIO drop.

2

Connect the BMXNRP020• module on the RIO drop via fiber cable to the BMXNRP020• module on the local rack.

Install fiber converter modules to extend the distance between RIO drops on the main ring or a sub-ring:

Step

Action

1

Install BMXNRP020• modules on the two RIO drops for which you wish to extend the distance.

2

Connect the BMXNRP020• module on one drop to the BMXNRP020• module on the next drop. The BMXNRP020• module uses small form-factor plugs (SFPs) (transceivers) for the fiber ports. Choose single-mode or multi-mode SFPs.

  • Use the multi-mode fiber module (BMXNRP0200) to connect the BMXNRP020• module to the ring if the distance between the BMXNRP020• and the next drop is less than 2 km.

  • Use the single-mode fiber module (BMXNRP0201) to connect the BMXNRP020• module to the ring if the distance between the BMXNRP020• and the next drop is in the range 2 km ... 5 km.

3

Interlink the two copper ports of the BMXNRP020• module with the two Ethernet ports of the BM•CRA312•0 on the drop.

4

To extend the distance between other RIO drops on a ring, repeat steps 1-3.

Isolation Requirements

Follow all local and national safety codes and standards.

If isolation is required in your network (e.g., if the local rack and RIO drops are on different grounding systems), then use fiber cable to connect devices that are on separate grounding systems.

Refer to the ground connections information in the Electrical installation guide to comply with EMC certifications and deliver expected performance.