Klemsan Klea 320P-D - RS485 Wiring and Computer Connection; Modbus RTU Message Format

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4
Quadrant
Energy Analyzer
4
Quadrant
Energy Analyzer
SECTION 4 MODBUS PROTOCOL
BÖLÜM 4 MODBUS PROTOCOL
4.1 RS485 Wiring Diagram
RS485 WIRING DIAGRAM
Any
device
Terminating
resistor
120Ω 120Ω
Terminating
resistor
Fig. 4-1 RS485 Wiring Diagram
4.2 Computer Connection
KLEA can communicate with PCs via USB-RS85 or RS232-RS485 converters.
PC USB-RS485 or RS232-RS485
converter
Fig. 4-2 Connection of KLEA to a PC
4.3 Message Format and Data Types of ModeBUS-RTU Protocol
KLEA implements modebus RTU protocol. Modebus RTU message format is
as follows
Tablo 4-1 Message Format
Start Address Function Data CRC End
≥ 3.5 byte 1 byte 1 byte 0-252 byte 2 byte ≥ 3.5 byte