Introduction - ABB C250 User Manual

1 INTRODUCTION

This Operating Guide describes the COMMANDER 250/V250 MODBUS serial data
communications option and must be used in conjunction with the standard User
Guide (part no. IM/C250 or IM/V250) supplied with the instrument.
Warnings.
• If the equipment is used in a manner not specified by the Company, the
protection provided by the equipment may be impaired.
• All equipment connected to the instrument's terminals must comply
with local safety standards (CEI/IEC 61010-1:2001-2).
Notes.
The MODBUS option provides the following facilities:
• Standard RS422/485 communications.
• MODBUS RTU protocol – for master (host computer) to slave
(COMMANDER 250/V250) system.
• 500V d.c isolation from external connections to the instrument.
• Two-wire or four-wire communication.
• 2400 or 9600 baud transmission rate.
• Parity-checking – odd, even or none.
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