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Current Limit for Thick Cable

For thick cable, the maximum current on the network is 16 Amps.  However, only 8 Amps is

permitted on a single network segment. 16 Amps can be drawn from a single power supply by

locating the power supply at the center point of two network segments, supplying 8 Amps to

each segment.

For thin cable, the maximum current permitted is 3 Amps.

The DeviceNet Master module consumes 450mA at 5VDC (typical) from the PLC backplane.

This power is used for module operation, The DeviceNet Master powers its network transceiver

from the 24VDC DeviceNet network power source. Linear power supplies are recommended for

the DeviceNet power source. The DeviceNet power source should not also be used for device

power. Transients caused by  I/O devices can cause communications errors and even create

bus-off conditions.

The DeviceNet specification recommends using a power tap to connect a power supply to the

network. The power tap should be appropriately fused for the current capacity of the bus cables.

The maximum current on the network depends on the cable type.

The DeviceNet network power supply must be grounded, but only at one point.  The V- signal

must be connected to protective earth ground at the power supply only.  If multiple power

supplies are used, only one power supply must have V- connected to earth ground.

DeviceNet Cable

Either DeviceNet thick cable or thin cable can be used.  Thick cable permits greater cable

lengths and higher current levels. Generally, thick cable is used for the trunk cable.  Thin cable

is normally used for shorter distances and is suitable for drop cables and for installations where

more cable flexibility is needed. Both thick cable and thin cable are 5-wire, multi-conductor

copper cable.  Two wires form a transmission line for network communications. A second pair

transmits network power.  The fifth conductor forms an electromagnetic shield. Most cables

have color coded leads which correspond to the color coding on the terminals on the DeviceNet

Master Module.

Power Requirements

The DeviceNet Master module consumes 450mA at 5VDC (typical) from the PLC backplane.

This power is used for module operation, The DeviceNet Master powers its network transceiver

from the 24VDC DeviceNet network power source. Linear power supplies are recommended for

the DeviceNet power source. The DeviceNet power source should not also be used for device

power. Transients caused by  I/O devices can cause communications errors and even create

bus-off conditions.

The DeviceNet specification recommends using a power tap to connect a power supply to the

network. The power tap should be appropriately fused for the current capacity of the bus cables.

The maximum current on the network depends on the cable type.

The DeviceNet network power supply must be grounded, but only at one point.  The V- signal

must be connected to protective earth ground at the power supply only.  If multiple power

supplies are used, only one power supply must have V- connected to earth ground.

LEDs and Connectors

The module’s three DeviceNet-compliant LEDS show its operating and communications status.

The RS-232 serial port is used for a computer connection during firmware upgrades. The

DeviceNet connector is a removable spring-clamp terminal. It provides bus continuity and can

be removed from the module without disrupting bus operation.

The DeviceNet Bus

Devices can be connected directly to the trunk cable, or to drop lines that are joined to the trunk

cable with taps. Taps can be mounted in junction boxes or panels. Drop lines and daisy-chains

are often used inside control panels where multiple devices are grouped together.  When using

drops with daisy-chains and branches, the maximum length from a tap to its farthest drop is 20 feet.

Bus Length

The maximum length of the trunk cable and drops both depend on the cable type and data rate.

Individual drops may not exceed 6 meters and are limited to one network node per drop.

However, the node may have multiple ports.

For each baud rate, the total drop length is the sum of all the drop lines of both cable types in

the network.

In addition, if the distance from a tap to the most distant device on its drop is longer than the

distance from the tap to the nearest terminating resistor, the drop line length also counts as part

of the trunk cable length (as well as the overall drop length).

Features

▪ Bus communications at all standard DeviceNet data rates (125k,

250k, 500k baud)

▪ Up to 255 bytes input data transfer and 255 bytes output data transfer

per slave.

▪ Up to 3972 bytes of input data transfer and 3972 bytes of output data

transfer per master.

▪ UCMM-capable Group 2 Server

▪ One or two I/O connections per Slave – Typically one connection is

used for Polled and the other is used for Strobe, Cyclic, or COS

▪ Supports Unconnected Message Manager (UCMM) with one proxy

connection per slave device

▪ Configurable global scan rate

▪ Supports Poll, Strobe, Cyclic and COS I/O connections, Fragmented

I/O and Explicit Messaging

▪ Configurable update rates for Poll and COS/Cyclic on a connection basis.

▪ Configurable response to loss of communication

▪ Firmware update via service port on module

The DeviceNet Master Module allows the CPU to send and receive data

over a DeviceNet network. It can act as master for up to 63 slaves on the

DeviceNet network. It can also be configured to simultaneously function

as a slave to another master on the bus.

DeviceNet is a communications network that transmits data between

control systems (for example: PLCs, PCs, VMEbus computers, and robot

controllers) and distributed industrial devices such as switches, sensors,

valve manifolds, motor starters, bar code readers, drives, displays, and

operator interfaces.

This module can be installed in any available I/O slot in any RX3i or

Series 90-30 backplane. It is compatible with PACSystems™ RX3i

IC695CPU310 CPU, release 3.5 or later. It is also compatible with any

Series 90-30 CPU except IC693CPU321 or IC693CPU340 with release

8.0 or later CPU firmware. Release 10 or later is recommended. Machine

Edition Logic Developer PLC version 3.0 SP1 Special 2 or later is

required. This module is not compatible with VersaPro™, Control, or

Logicmaster™ programming software. A Series 90-30 Hand-Held

Programmer (IC693PRG300) cannot be used for configuration.

Module Features

• Supports eight client connection to the RX3i Controller data set specified in the configuration. [RBE

supported only

on one Client connection associated with a specified port -Refer to GFK-2949B for details]

• Supports Interrogation and RBE for Single Point and Double Point data.

• Supports Interrogation and RBE for Regulated Step.

• Supports Interrogation and Measured data sets for Scaled, normalized, and single precision Float.

• Supports 56-bit IEC 60870-5-104 time format, with the default being 56-bit time format.

• Supports Time Set, and query of the RX3i Controller CPU Clock in UTC time.

• Cause of Transmission size is two octets.

RX3i Interface specifications:

• Up to four EIS001 per RX3i, as allowed by available power and slots.

• Module can be installed in any available RX3i main rack I/O slot.

• Module supports insertion into and removal from an RX3i backplane which is under power.

• Firmware upgrade through RX3i CPU using WinLoader software utility.

Introduction

The PACSystems RX3i Ethernet IEC 104 Server Module, catalog number IC695EIS001. implements the IEC 60870-5-104

communications protocol. It permits a PACSystems RX3i controller to be connected to an Ethernet network using a

standard TCP/IP connection scheme, allowing an IEC 104 Client to poll data from the Server, as well generate unsolicited

communications from the Server back to the Client.

Two auto-sensing 10BaseT/100BaseTX RJ-45 shielded twisted-pair Ethernet ports permit direct connection to either a

10BaseT or 100BaseTX IEEE 802.3 network without an external transceiver. Line, Star and Daisy Chain topologies are

supported.

The RX3i Ethernet IEC 104 Server Module hosts the IEC104 Server side protocol on a common RX3i ETM001-Jx module

hardware platform. Thus, many of the specifications and behaviors are shared with the ETM001 module including

protocol support. IC695EIS001 is an Ethernet-connected module that fits in the RX3i backplane and permits the RX3i

to behave as a Server on the IEC104 network. The data exchanges between the EIS001 module and IEC104 Client(s) are

configurable, using a single COMMREQ instruction in the ladder logic or Structured Text program.

The PACSystems RX3i IEC 61850 Ethernet Communication Module, catalog number IC695ECM850. or ECM850.

connects a PACSystems RX3i controller to an IEC 61850 network, enabling the controller to act as an IEC 61850 Client

and communicate with Intelligent Electronic Devices (IEDs, IEC 61850 Servers) on the network using the IEC 61850

protocol.

Sweep Impact of ECM850

The impact of the ECM850 on RX3i CPU sweep time is a function of the number of ECM850 modules in the RX3i

hardware configuration (four maximum) and the I/O data size configured for each ECM850 module. The table below

shows the measured sweep impact of a single ECM850 module for a range of I/O data sizes. Use the data in this table

to calculate expected impact on RX3i CPU sweep times. The configured IO Data size will be available in the message

zone of the IEC 61850 Configurator after configuration validation.