1
Introduction
The most important characteristics of the MELSEC ST series are summarized in this installation
description. This description is designed to help the experienced user quickly start-up the mod-
ules. Additional information and a detailed mounting and wiring description is in the MELSEC ST
series operating manual. This documentation is provided solely as a quick reference.
1.1
General Description
The MELSEC ST series is a modular input and output system which is connected as slave sta-
tion to a PROFIBUS/DP network. An ST series station consists of
쎲
a head station to which the PROFIBUS is connected.
쎲
Power supply modules.
쎲
Digital and analog I/O modules.
The I/O modules can be combined as desired according to the requirements.
1.2
Special Features
Reduced wiring effort
–
External voltages
for supplying sensors and actuators are connected to the power distribution modules of
the ST series only. The other system modules are supplied with power via internal connec-
tions. Wiring requirements are significantly reduced because the supply voltage does not
need to be connected to each individual module.
–
PROFIBUS connection
Only the head station is connected to the PROFIBUS/DP network.
–
Connection of the I/O modules
Peripherals are connected either via spring clamp terminals, (into which the wires are just
inserted), or via conventional screw clamp terminals.
Flexible System Set-up
The number of inputs and outputs can be adapted easily to the application. Digital modules with
2, 4, and 16 inputs, and with 2 and 16 outputs are available. Up to 63 I/O modules (max. 26 ana-
log I/O modules) can be connected to one head module.
Simple Service
The electronics modules are plugged into a base module to which the peripheral signals are
connected. The base module is mounted on a DIN rail. Electronic modules can be replaced in
operation. No tool is required to do this. The GX Configurator DP is available to configure the
system.
Introduction
MELSEC ST Series
7
