Campbell CMP11-L, Instruction Manual

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CMP6-L, CMP11-L, and CMP21-L Pyranometers
TABLE 7-2. CMP6 and CMP11 Single-Ended Connections to Campbell Scientific Dataloggers
Color
Description CR9000(X), CR5000,
CR3000, CR1000,
CR800
CR510, CR500,
CR10(X)
21X, CR7, CR23X
White Signal (+) SE Analog SE Analog SE Analog
Black Signal (–) AG
Clear Shield G
7.2.3 CMP21 Wiring
A CMP21 purchased from Campbell Scientific has different
wiring than a CMP21 purchased directly from Kipp & Zonen.
NOTE
The CMP21’s pyranometer can be measured using either differential analog
channels or single-ended analog channels. A differential voltage measurement
is recommended because it has better noise rejection than a single-ended
measurement. If a differential channel is not available, a single-ended
measurement can be used.
A single-ended channel and a voltage excitation channel are used to measure
the CMP21’s internal thermistor.
Connections to Campbell Scientific dataloggers for a differential measurement
are given in TABLE 7-3. A user-supplied jumper wire should be connected
between the low side of the differential input and ground (AG or
) to keep
the signal in common mode range. Connections to Campbell Scientific
dataloggers for a single-ended measurement are given in TABLE 7-4.
TABLE 7-3. CMP21 Differential Connections to Campbell Scientific Dataloggers
Wire Color
Wire Label/
Description CR9000(X),
CR5000, CR3000,
CR1000, CR800
CR510, CR500,
CR10(X)
21X, CR7, CR23X
White Pyranometer Sig DIFF Analog High DIFF Analog High DIFF Analog High
Blue Pyranometer Ref *DIFF Analog Low *DIFF Analog Low *DIFF Analog Low
Yellow Thermistor Volt Excite VX or EX E EX
Black Thermistor Sig Single-ended analog Single-ended analog Single-ended analog
Brown Thermistor Ref AG
Clear Shield G
* Jumper to AG or
with user-supplied wire.
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