RainWise PVmet 500 Series, Руководство пользователя

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Table 5: SunSpec model 307, base meteorological
Field
Type Address
Offset
Block
Offset
Size Name Label Value Type Unit SF R/W Description Notes
Header 0 1 ID Base Met 307 uint16 R Base Meteorological Model
This model
supersedes
model 301
Header 1 1 L 11 uint16 R Model Length
Fixed
Block
2 0 1 TmpAmb
Ambient
Temperature
int16 C -1 R
Fixed
Block
3 1 1 RH
Relative
Humidity
int16 Pct R
Fixed
Block
4 2 1 Pres
Barometric
Pressure
int16 HPa R
Fixed
Block
5 3 1 WndSpd Wind Speed int16 m/s R
Fixed
Block
6 4 1 WndDir
Wind
Direction
int16 deg R
Fixed
Block
7 5 1 Rain Rainfall int16 mm R
Fixed
Block
8 6 1 Snw Snow Depth int16 mm R
Fixed
Block
9 7 1 PPT
Precipitation
Type
int16 R
Precipitation Type (WMO
4680 SYNOP code
reference)
Fixed
Block
10 8 1 ElecFld Electric Field int16 Vm R
Fixed
Block
11 9 1 SurWet
Surface
Wetness
int16 k Ω R
Fixed
Block
12 10 1 SoilWet Soil Wetness int16 Pct R
PVMET-500HOLDING REGISTERS
A complete table of all the SunSpec holding registers is shown in the appendix.
The PVmet 500’s first register C SunSpec ID is located at 40,001. This document assumes base 1 addressing is being used. If the host
system uses base 0 addressing, decrement the starting register values shown by 1.
All registers in the SunSpec Register map are read-only. Use the Modbus 03 command to access the data. Do not attempt to read
beyond the specified map, the PVmet-500may not respond.
SCALING
Holding registers only support integer values (no decimal points). To improve resolution many of the measured values are scaled up by
a factor of 10 or 100. The Modbus master must convert the data point to a floating-point variable and multiply by the “scale factor”
indicated in the table below. For example, a temperature of 25.3°C will be reported as 253. Multiplying by the scale factor of 0.1 results
in a final value of 25.3.
RAINFALL OPERATION
The SunSpec specification for rainfall mandates that the rainfall register 40 077 will reset after each Modbus poll. To effectively use
this parameter, the host system must implement a separate running rainfall counter variable in the host system. The contents of the
rainfall register must then be added to this variable on EVERY read. As this may be difficult to implement on many systems a second
register has been provided outside the SunSpec register map. The separately provided value is a running counter in mm.