Use Of Communication - Siemens SICAM P35 Manual

Communication

6.1 Use of Communication

6.1 Use of Communication
RS485 port of this product supports MODBUS-RTU communication protocol. Even parity check is the default
setting for data byte check, namely 8E1 (8-digit data, even parity check, 1 stop bit) format. MODBUS-RTU com-
munication protocol can also be configured to odd parity check or no verification, namely 8O1 (8-digit data, odd
parity check, 1 stop bit), 8N1 (8-digit data, no parity check, 1 stop bit), or 8N2 (8-digit data, no parity check, 2
stop bits) format. Baud rate of communication port could any of 600 bps, 1,200 bps, 2,400 bps, 4,800 bps, 9,600
bps, 19,200 bps and 38,400 bps.
RS485 port of this product should be connected using Shield Twisted Pair. When wiring, layout of the entire
network should be considered: length and orientation of communication cable, position of upper computer,
matched resistance at network end-point, communication converter, network scalability, network coverage,
EMI, etc.
Note
1. Wiring should be conducted strictly in accordance with requirement.
2. The power meter requiring no communication temporarily should be connected to RS485 network for easy
diagnosis and test.
3. The shielding layer side of cable connected with upper computer should be reliably earthed (PGND: ground,
cubicle, cabinet, etc.) to avoid two-point or multi-point earthing.
4. Shield Twisted Pair should be used for RS485 bus cable. For two twisted pairs, different colors are recom-
mended, one color for "A" side and another color for "B" side of 485 communication port.
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SICAM P35 P36, 3-phase Multi-Function Power Meter, User Manual
E50417-H8940-C562-4, Release Date 06.2018