Lenze ESVZAR0 RS-485 - Manual (Page 7)

5 CMVMB401C
Introduction
2 Introduction
This reference guide assumes that the reader has a working knowledge of the Modbus RTU Protocol and familiarity
with the programming and operation of motion control equipment. This guide is intended as a reference only.
Modbus is an internationally accepted asynchronous serial protocol designed for commercial and industrial automation
applications. The Modbus RTU architecture is based upon a PLC to device communication structure and, as such
is Master-Slave in orientation. The SMV drive, in this case, always acts as the slave in this network, responding to
commands and requests from the Master.
While the Modbus RTU protocol does not specify the physical layer, the ESVZAR0 module uses the RS-485 physical
interface which is quite common and well suited for the industrial environment. The ESVZAR0 module provides both
galvanic and optical isolation of this physical interface.
2.1 Module Specifications
Table 2 identifies the Modbus serial communication specifications. If the specification is fixed (non-adjustable)
the value is shown under “Range”, if the specification is selectable, Table 2 identifies the Parameter and available
range of selections.
Table 2: Modbus Specifications
Description Type Range
Baud Rate Selectable P411 (2400, 4800, 9600, 19200, 38400, 57600, or 115200 bps)
Data Bits Fixed 8
Parity / Stop Bits Selectable P412 (None/1, None/2, Even/1, Odd/1)
Network Address Selectable P410 (1 - 247)
Typical communications between master and slave would be:
• Write commands from Master
• Run command
• Frequency Reference
• Modification of Drive operating parameters
• Requests from Master
• Reporting of drive status
• Fault status (and fault history)
The SMVector drive most nearly conforms to the Modicon® Micro 84 in capabilities. This may be of importance
when configuring networks for DDE Servers.