Campbell Wintersense SDI-12, Руководство по эксплуатации продукта

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7.2.3 Identify measurement and measurement parameter
commands
Version 1.4 compliant sensors must respond to identify commands for each type of measurement
command and each parameter with a command. The identify commands return how many
variables will be returned with a given measurement command and the time it will take the
sensor to respond, without the time penalty of actually taking the measurement. The specific
identify parameter commands will return a SHEF code, the measurement units, and the type of
measurement (such as sample, count, or average).
Table 7-3: Identify commands for the Wintersense SDI-12
SDI-12 command
1
Description Sensor response Comment
aIM! , aIMC!
Identify measurement
for
M
commands
atttn
ttt
: response time
(seconds)
n
: # of values returned
aIM1!
...
aIM9!
Identify measurement
for
M
commands
atttn
ttt
: response time
(seconds)
n : # of values returned
aIC!
,
aICC!
Identify measurement
for
C
commands
atttnn
ttt
: response time
(seconds)
nn
: # of values returned
aIC1!
...
aIC9!
Identify measurement
for
C commands
atttnn
ttt : response time
(seconds)
nn
: # of values returned
aIV!
Identify measurement
for
V
command
atttn
ttt
: response time
(seconds)
n
: # of values returned
aIM_001!
, …
aIMC_
,
aIC_
,
aICC_
Identify measurement
parameters
a, TR, C
TR = SHEF CODE for
Temperature, road
surface
aIM_002!
, …
aIMC_
,
aIC_
,
aICC_
Identify measurement
parameters
a, TA, C
TA = SHEF CODE for
Temperature, air
aIM_003!
, …
aIMC_ , aIC_ , aICC_
Identify measurement
parameters
a, XR, %
XR = SHEF CODE for
Humidity, relative
Wintersense SDI-12 12