YOKOGAWA UTAdvanced Series, User Manual

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1-2
IM 05P07A01-01EN
1.2 RS-485 Communication (for UTAdvanced with
RS-485 Communication)
Four protocols are supported on the RS-485 interface: PC link communication protocol,
Modbus/RTU communication protocol, Modbus/ASCII communication protocol, and
ladder communication protocol.
RS-485 communication allows data to be collected from the UTAdvanced and data to be
set on the UTAdvanced easily from a host computer.
1.2.1 Communication Specifications
Communication specifications
Host communication (PC link, Modbus, Ladder)
Communication interface RS-485
Communication method 4-wire type half-duplex or 2-wire type half-duplex,
asynchronous operation, non-procedural
Connection method 1:n multi-drop method (n = max. 31)
Communication distance Max. 1200 m
Baud rate 600, 1200, 2400, 4800, 9600, 19200, 38400 bps *
*: 38400 bps: UT75A/UT55A/UT35A/UP55A/UP35A;
Only of suffix code Type 3 = 1
UT52A/UT32A/UT32A-D/UP32A/UM33A;
Only of suffix code Type 2 = 1
Start bit 1 bits
Data length Modbus communication (ASCII): Fixed at 7 bits
Modbus communication (RTU): Fixed at 8 bits
PC link communication: 7, 8 bits
(with checksum / without checksum)
Ladder communication: Fixed at 8 bits
Parity bit NONE (none), EVEN (even), ODD (odd)
Stop bit 1, 2 bits
Example:
PC
For details on wiring, refer to Operation Guide or
User’s Manual.
Up to 31 connected slaves with a maximum length of 1200 m
Model: ML2 of YOKOGAWA is recommended.
RS-485/
RS-232C
converter
RS-485
communication address = 01
RS-485
communication address = 05
RS-485
communication address = 10
RS-485
communication address = 20