KTA-282 Modbus TCP Weather Station Gateway
raw pressure is affected by other weather events such as temperature, humidity, and elevation. The
options are:
Reading
Barometric Reduction Method
0
User offset
1
Altimeter Setting
2
NOAA Bar Reduction (for Vantage Pro 2 this is the default and cannot
be changed)
Table 15: Barometric Reduction Method Description
6.
Index to the minute within the hour holds the current progress of the hour used for rain rate calculations –
from 0 to 59.
7.
Holding register 78 contains the status of the loop 2 command. If 1, loop 2 is being successfully received.
To obtain the loop 2 data, the hardware must be either a Vantage Pro2 (Firmware revision 1.90 or later) or
a Vantage Vue.
Functionality
Unit Conversions
NOTE: if your temperature displays incorrectly below 0°C, update to the latest firmware at
oceancontrols.com.au
The units of the readings can be changed by writing to the Modbus holding registers shown in table 16. The
following table shows the multiplier and unit. For example if a 1 was written to holding register 106 then the
atmospheric pressure readings would be in mmHg and have to be multiplied by 0.1.
Holding
Register
Variable Type
Conversion
1
Registers Affected
105
Temperature
0 = 0.1 °F
1 = 0.1 °C
5, 7
105
Extra Temperatures
2
0 = 1 °F + 90
1 = 1 °C + 50
11, 12, 13, 14, 15, 16, 17, 18
106
Pressure
0 = 0.001 inHg
1 = 0.1 mmHg
2 = 0.1 mb
3 = 0.001 atm
4
107
Wind Speed
0 = 1 mph
1 = 1 kph
2 = 1 knots
3 = 1 m/s
4 = 1 ft/s
8, 9
108
Rain
3
0 = 0.01 in
1 = 1 mm
24, 27, 29, 30, 31, 32, 33, 34
Table 16: Unit Conversion Modbus Register Listing
Notes:
1. The units used by the gateway:
Symbol
Unit
°F
Farenheit
°C
Centigrade or Celcius
inHg
Inches of Mercury
mmHg
Millimetres of Mercury
mbar
Millibar
atm
Atmospheres
mph
Miles per Hour
kph
Kilometeres per Hour
7/05/2013
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