Rockwell Automation MagneMotion 700-0871-00, User Manual

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Node Controller Overview
Node Controller Loading
Node Controller Hardware User Manual 45
Rockwell Automation Publication MMI-UM013B-EN-P - April 2020
Node Controller Loading
When using RS-422 for motor communication, the load on the node controllers is physically
limited by the number of nodes that can be connected to a node controller. When using Ether-
net for motor communication, there is no physical limit to the number of nodes that are con-
nected to the node controller.
When running as the HLC, there is an additional load on the node controller due to communi-
cation with the host. When using multiple node controllers, the node controllers without the
HLC function have no additional load and can support the maximum number of multi-port
nodes. In systems where there are multiple node controllers, split the load evenly between all
node controllers.
Multi-port node types are nodes that connect multiple paths and require multiple connections
to the node controller such as Relay, Diverge, or Merge nodes. These types of nodes result in
the same amount of load on the node controller even if they have different numbers of paths
that are connected to the node controller. Single-port node types (Simple and Terminus) pres-
ent a negligible load. When using two Terminus nodes to pass vehicles between paths, they
count as one multi-port node due to the increased communication load.
Multi-port node types are nodes that connect multiple paths and require multiple connections
to the node controller such as Relay, Diverge, or Merge nodes. These types of nodes result in
the same amount of load on the node controller even if they have different numbers of paths
that are connected to the node controller. Single-port node types (Simple and Terminus) pres-
ent a negligible load. When using two Terminus nodes to pass vehicles between paths, they
count as one multi-port node due to the increased communication load. See
Table 3-1 for node
controller loading using the different motor communication types.
Using RS-422 Communication
When using RS-422, the total load on the NC-S, NC LITE, and NC-12 node controllers is lim-
ited by the number of connections to the node controller. Even though there is a physical limit
to the number of nodes that are connected to the node controller, connections must be limited
based on the load they place on the processor as shown in
Table 3-1 .
When using RS-422, all motors in a specific path are daisy chained together. The ends of the
motor chains that start or end at a node are connected to a node controller. The number of
RS-422 connections on a node controller determines the maximum number of motor chains
that can be connected.
Using Ethernet Communication
When using Ethernet, the total load on the node controllers is limited by the processing power
of the node controller. Since there is no physical limit to the number of nodes that are con-
nected to the node controller, connections must be limited based on the load they place on the
processor as shown in
Table 3-1 .