Schneider Electric user manual Introduction to the LUFP7 Gateway, Terminology

1. Introduction

1.2. Introduction to the LUFP7 Gateway

The LUFP7 gateway allows a master located on a Profibus-DP network to enter into a dialogue with the slaves on a Modbus RTU network. This is a generic protocol converter operating in a way which is transparent to the user.

This gateway allows you to interface many products marketed by Schneider Electric with a Profibus-DP network. These include TeSys U motor starters, Altivar drivers and Altistart soft start- soft stop units.

1.3. Terminology

Throughout this document, the term “user” refers to any person or persons who may need to handle or use the gateway.

The term “RTU”, which refers to the Modbus RTU communication protocol, will be omitted most of the time. As a result, the simple term “Modbus” will be used to refer to the Modbus RTU communication protocol.

As is still the case with all communication systems, the terms “input” and “output” are somewhat ambiguous. To avoid any confusion, we use a single convention throughout this document. So the notions of “input” and “output” are always as seen from the PLC, or the Profibus-DP master.

Hence, an “output” is a command signal sent to a Modbus slave, whereas an “input” is a monitoring signal generated by this same Modbus slave.

The diagram below shows the flows of “inputs” and “outputs” exchanged between a Profibus-DP master and Modbus RTU slaves via the LUFP7 gateway:

Profibus-DP Master

INPUTS

OUTPUTS

LUFP7

Gateway

490 NAE 911 00

Altistart 48

Modbus RTU Slaves

8