ProSoft Technology MVI56-103M - Manual (Page 112)

Reference MVI56-103M ♦ ControlLogix Platform
User Manual IEC 60870-5-103 Master Communication Module
Page 112 of 152 ProSoft Technology, Inc.
February 22, 2013
5.5 Master Driver
The Master driver supported on each of the two application ports of the module
emulates an IEC 60870-5-103 Master device. Configuration of each port is
independent and each port should be connected to physically separate serial
networks.
Each port on the module communicates with one or more controlled stations
using what are referred to as sessions. A session represents a controlled device
(slave) with a unique Data Link layer address. Each session (controlled slave
device) contains one or more data sets (sectors) that are defined by the vendor
of the device.
Up to thirty-two sessions (or less on some modules) can be defined on the
module, with each session being assigned to only one application port. Within
each session, up to five sectors can be defined. This system permits a very
flexible assignment of resources in the module. The definition of the data
associated with each sector in the system is defined by the user in the
configuration file.
Note: The IEC 60870-5-103 specification requires support only for unbalanced transmission mode.
No support is given in the protocol for the balanced mode and the module does not support this
mode.
The following diagram shows the functionality of the Master driver:
1 The Master driver is configured as specified by the IEC103M.CFG file.
2 The Master will construct control commands using the data in the database.
3 The Master will send these commands and class polls out on the serial
network.
4 Response messages or spontaneous messages generated by controlled
devices on the serial network are received by the Master driver.
5 Monitor data received by the Master is passed to the module’s database and
passed to the processor.