Communicating with S7-300 or S7-400

Help Contents

Introduction

Fernhill SCADA supports these types of connection to Siemens S7-300 and S7-400 PLC Devices:

Connection using an MPI adapter
Connection using an Ethernet Module

Connection Using an MPI Adapter

You can connect Fernhill SCADA to S7-300/400 PLC Devices using an MPI adapter:

PC connected to two S7-300 PLC Devices via an MPI adapter

These MPI adapters are supported:

HMI Adapter 6ES7 972-0CA11-0XA0
PC Adapter 6ES7 972-0CA23-0XA0, 6ES7 972-0CA22-0XA0, 6ES7 972-0CA21-0XA0
TS Adapter 6ES7 972-0CA34-0XA0, 6ES7 972-0CA33-0XA0, 6ES7 972-0CA32-0XA0

Connection Cables

The MPI adapter can connect directly to a serial port on a Personal Computer (PC). The serial port on a PC is usually a 9 pin D-subminiature connector. This cable is suitable to connect the MPI Adapter to a computer with a 9 pin D-subminiature connector:

6ES7901-0BF00-0AA0 - 5 m length

As an alternative you can create your own cable using null-modem wiring:

MPI Adapter		PC
RXD	2	3	TXD
TXD	3	2	RXD
DTR	4	6	DSR
GND	5	5	GND
DSR	6	4	DTR
RTS	7	8	CTS
CTS	8	7	RTS

Note: All other pins not shown in the above diagram have no connection.

Fernhill SCADA Configuration

Configure one Siemens S7 MPI Channel Tag. Configure one Siemens S7 Serial PLC Tag for each PLC on the MPI bus.
The Siemens PC and TS adapters support two RS-232 communication speeds: 19200 and 38400 Baud. The speed is selected by a switch on the side of the adapter. The Siemens HMI adapter supports only 9600 Baud. The Mode settings of the Siemens S7 MPI Channel Tag should match the RS-232 speed of the MPI Adapter.

RS-232 Speed Channel Mode

9600 Baud=9600 Parity=O Data=8 Stop=2

19200 Baud=19200 Parity=O Data=8 Stop=2

38400 Baud=38400 Parity=O Data=8 Stop=2
When powered up, HMI and PC adapters require configuration to join the MPI bus. The Fernhill SCADA Siemens S7 driver automatically configures HMI and PC adapters using the settings from the Siemens S7 MPI Channel Tag.
TS adapters are configured offline using the Siemens Teleservice configuration tool. TS adapters retain their settings between power cycles. The Fernhill SCADA Siemens S7 driver does not configure TS adapters.

RS-232 Speed	Channel Mode
9600	Baud=9600 Parity=O Data=8 Stop=2
19200	Baud=19200 Parity=O Data=8 Stop=2
38400	Baud=38400 Parity=O Data=8 Stop=2

For a detailed walkthrough about manually configuring tags for MPI connection refer to Configuring Tags for Siemens S7 MPI Communication.

Connection Using a CP-343-1 or CP-443-1 Ethernet Module

You can connect Fernhill SCADA to an S7-300/400 PLC using a CP-343-1 or CP-443-1 Ethernet module:

PC connected to an S7-300 PLC via Ethernet

For a detailed overview of setting up an S7-300 or S7-400 Ethernet module refer to Siemens S7-300/400 Ethernet Connection Guide.

If the Ethernet module configured, you can use the Siemens S7 TCP Autodetect Wizard to try and locate the PLC on the network.

Further Information

Configuring Tags for Siemens S7 MPI Communication

To learn how to configure tags for Siemens S7 MPI connected PLC Devices.

Siemens S7-300/400 Ethernet Connection Guide

For how to configure an S7-300/400 Ethernet module and Fernhill SCADA to work together.

Siemens S7 TCP Autodetect Wizard

For how to search a network for Siemens S7 PLC Devices and automatically create tags for any PLC Devices found.

Siemens S7 Driver

For information on the Siemens S7 Driver.

Fernhill SCADA Drivers

For information about other drivers available in Fernhill SCADA.

Glossary

For the meaning of terms used in Fernhill SCADA.