4. Configuration
84
Notes:
Instances per Serial Interface (COMs):
Due to its characteristics, each serial interface supports
only one communication protocol instance. Examples of instances compatible with serial interfaces:
MODBUS RTU Master and MODBUS RTU Slave.
Instances per Ethernet Interface
(NETs):
Ethernet Interfaces support more than one
communication protocol instance, as described in the table. Examples of instances compatible with
Ethernet interfaces: MODBUS Client, MODBUS Server, DNP3 Client, among others.
Instances per CPU:
The sum of the communication protocols instances, declared in Serial and
Ethernet interfaces, cannot exceed the maximum number of instances supported by the CPU.
Control Center per CPU:
It refers to any client device connected to the CPU via DNP3, IEC 60870-
5-104 or MMS protocols (IEC 61850). This field informs the maximum amount of client devices,
control center type, supported by the CPU. It corresponds to the sum of all client devices of the
instances of DNP3 Server, IEC 60870-5-104 and MMS server communication protocols (not
including the masters and clients of MODBUS RTU Slave and MODBUS Server protocols).
Mappings per CPU:
A “mapping” is the relationship between an internal application variable and an
object of the application protocol. This field informs the maximum number of mappings supported
by the CPU. It corresponds to the sum of all mappings made within the instances of communication
protocols and their respective devices (see following table).
Mapped points:
It refers to the maximum number of mapped points supported by the CPU. Each
mapping supports one or more mapped points, depending on the size of the data when used with
variables of type ARRAY.
DNP3 connections:
It refers to the sum of the maximum number of DNP3 Client and DNP3 Server
connections of a CPU HX3040. It cannot exceed the total number of connections reported in the
table for the correct operation of the application.
Requisition per CP
U: The sum of the requests of the communications protocols, declared on
devices, may not exceed the maximum number of requests supported by the CPU.
Table 4-28 informs the maximum configuration and operation limits of MODBUS/DNP3
communication protocols, and Serial/Ethernet interfaces.
MODBUS
RTU
Master
MODBUS
RTU
Slave
MODBUS
Client
MODBUS
Server
DNP3
Client
DNP3
Server
IEC 104
Server
Devices per instance
64
1(¹)
64
64(²)
32
5(³)
5(
4
)
Requests per instance
128
NA
128
NA
128
NA
NA
Requests per device
32
NA
32
NA
32
NA
NA
Simultaneous requests per
instance
1
1
128
64
32
5
5
Simultaneous requests per
device
1
1
8
64
1
1
1
Table 4-28. Limits of Communication Protocols
Notes:
Devices per instance:
Master or Client Protocols:
Number of slave or servers devices supported by each instance of
Master or Client protocol.
MODBUS RTU Slave Protocol:
The limit (¹) regards the serial interfaces that do not allow a
slave to communicate simultaneously via the same serial interface with more than one master
device. It is not necessary, nor possible, declare or configure the Master device under instance of
the MODBUS RTU Slave protocol. The Master device will have access to all mappings made
directly on the instance of MODBUS RTU Slave protocol
