AccuEnergy AcuRev 1200 Series, User Manual

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11
AcuRev
1200
Wiring:
Figure 2-6 wiring
Communication:
AcuRev1200 communication utilizes RS485 port, via Modbus-RTU protocol. The
wiringterminals are A, B, S. "A" is called differential signal"+", "B" is called differentialsignal"-",
"S" is connected to the cupper net of the Shielded Twisted Pair(STP) in the shielding layer.
The maximum distance of STP is 1200m. The distance will be shorter if more devices are on
the same communication link or using a higher baud rate.
If the master device does not have RS485 but RS232 port, a RS232/485 converter can
be utilized. Typical RS485 network topologies include line, circle and star.
In order to improve communication quality:
1. High-quality Shielded Twisted Pair is very important, AWG22 (0.6mm
2
) or bolder is
recommended. Two cables should be different colors.
2. Pay attention to "single point earthing". It means there is only one point of the
shielding connected to ground in a single communication link.
3. Every A(+) should be connected to A(+), B(-) to B(-), or it will influence the network,
even damage the communication interface.