Planning a High-Capacity Daisy Chain Loop

Original instructions

Introduction

A high-capacity daisy chain loop incorporates in the . The following are possible:

RIO sub-rings
DIO sub-rings
DIO clouds
fiber cable implementations that use use BMXNRP020• fiber converter modules

Planning a High-Capacity Daisy Chain Loop

An M580 local rack contains a and supports a maxiumum of eight Ethernet communication modules, including BMENOC0301 or BMENOC0311 modules and BMENOS0300 network option switch modules. Only one of these modules can be a BMENOC0321 network option switch module. The number of communication modules with DIO scanning service depends on your CPU selection.

If you use both RIO and distributed equipment in the , use a CPU that supports both RIO and DIO scanning, referred to in this guide as a CPU with Ethernet I/O communication service. These are the CPUs with commercial references that end in 40.

NOTE:

RIO drops maintain their determinism and cable redundancy in a high-capacity daisy chain loop network. If a communication disruption (for example, a broken wire) occurs on the main ring or any of the RIO sub-rings, the network will recover within 50 ms.
To keep the network recovery time within the 50 ms limit, a maximum of 32 devices (including a CPU with Ethernet I/O communication server service in the local rack) are allowed on the main ring.
A maximum of 31 RIO drops (each drop containing a BM•CRA312•0 X80 EIO adapter module) are allowed on the RIO network.
To diagnose a break in a daisy chain loop, refer to the diagnostics chapter in the BMENOS0300 guide.

Connecting Distributed Equipment to the RIO Network

This BMEP58••40 CPU (with Ethernet I/O scanning service) on a local rack supports an RIO main ring with distributed equipment connected to the RIO network:

The M580 CPU is connecected to the main ring.

The BMENOC0321 control network module is connected to the control network, creating transparency between the device network and the control network.

The DIO sub-ring is connected to the main ring through a dual-ring switch (DRS).

RIO drops are connected to the main ring through BM•CRA312•0 (e)X80 EIO adapter modules.

(dual-ring switch) A ConneXium extended managed switch that has been configured to operate on an Ethernet network. Predefined configuration files are provided by Schneider Electric to downloaded to a DRS to support the special features of the main ring / sub-ring architecture.

An Ethernet-based network that contains 3 types of RIO devices: a local rack, an RIO drop, and a ConneXium extended dual-ring switch (DRS). Distributed equipment may also participate in an RIO network via connection to DRSs or BMENOS0300 network option switch modules.

One of the three types of RIO modules in an Ethernet RIO network. An RIO drop is an M580 rack of I/O modules that are connected to an Ethernet RIO network and managed by an Ethernet RIO adapter module. A drop can be a single rack or a main rack with an extended rack.

(distributed I/O) Also known as distributed equipment. DRSs use DIO ports to connect distributed equipment.

A group of distributed equipment that is not required to support RSTP. DIO clouds require only a single (non-ring) copper wire connection. They can be connected to some of the copper ports on DRSs, or they can be connected directly to the CPU or Ethernet communications modules in the local rack. DIO clouds cannot be connected to sub-rings.

(central processing unit) The CPU, also known as the processor or controller, is the brain of an industrial manufacturing process. It automates a process as opposed to relay control systems. CPUs are computers suited to survive the harsh conditions of an industrial environment.

For a defined application and architecture, you can predict that the delay between an event (change of value of an input) and the corresponding change of a controller output is a finite time t, smaller than the deadline required by your process.

The main ring of an Ethernet RIO network. The ring contains RIO modules and a local rack (containing a CPU with Ethernet I/O scanner service) and a power supply module.