Weidmuller Transclinic 16i+ Bedienungsanleitung Seite 74

In terms of configuration of the Scada or PLC acting as Modbus client please follow
these recommendations:
• Set the Modbus client timeout to 1 second
• The recommended practical polling interval per slave is 20 seconds. This is a
good tradeoff between unnecessary network traffic (and database size) and time
resolution. Keep in mind that the sun, the clouds and the MPP of the inverter do
not change significantly in 20 seconds!
• For the most efficient use of the PV site network bandwidth we recommend that all
the Modbus registers of each Transclinic are read in one single, function code 0x04
"read input registers", request spanning from registers 1 to 35. This request will not
create any 0x02 "illegal data address" exception due to the "gaps" in the register
table.
• The averaging window length is 2.5 seconds.
The system is providing several measurement and alarm information via Modbus.
This information are listed below:
• Averaged PV system voltage
• Averaged PV current for each input
• Averaged PCB temperature
• Status of the digital inputs
• Alarm flag: PV system undervoltage (user-configurable threshold)
• Alarm flag: Individual input undercurrent (user-configurable threshold)
• Alarm flag: Blown fuse
• Alarm flag: PCB over temperature (fixed threshold 70 °C)
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