Valid values for the
SDIAddress
are 0 through 9, a through z, and A through Z; alphabetical
characters need to be enclosed in quotation marks (for example,
“A”
). Also enclose the
SDICommand
in quotation marks as shown. The
Destination
parameter must be an array.
The required number of values in the array depends on the command; see
FillNAN
and
WaitonTimeout
are optional parameters (refer to
CRBasic Editor
help for more
information).
7.3 Siting
The TempVue 20 SDI-12 is intended for air temperature measurements only. The general EPA
guidance for standard meteorological stations is to locate the sensor over an open, level area at
least 9 m (29.5 ft) in diameter. The surface should be covered by short grass or the natural earth
surface where grass does not grow. Sensors should be protected from thermal radiation and
adequately ventilated. Protect the filter at the top of the sensor from exposure to liquid water.
Figure 7-1. Clearances
The sensor should be installed at a standard measurement height which varies depending on the
guides being used:
l
1.5 m (4.92 ft) (AASC)
l
1.25 to 2.0 m (4.1 to 6.5 ft) (WMO)
l
2.0 m (6.5 ft) (EPA)
See
(p. 18) for a list of references that discuss temperature sensors.
TempVue 20 SDI-12 PT-100 Class A, Precision Air Temperature Sensor
10
