Campbell Scientific HC2S3 Temperature and Relative Humidity Probe - Manual (Page 18)

Model HC2S3 Temperature and Relative Humidity Probe
The HC2S3 draws approximately 2 mA powered from 12V. The HC2S3 can
be continuously powered from the 12V terminal, or power can be switched
with the SW12V terminal to conserve battery life. When power is switched, a
three-second warm-up time is required. Using the SW12V terminal on the
CR10X datalogger requires a user-supplied jumper wire connected between the
SW 12V CTRL terminal and a Control Port (C1 to C8).
When measuring the HC2S3 with single-ended
measurements, the yellow and gray leads must both be
connected to AG on the CR10(X) and CR500/CR510 or to
on the CR1000, CR5000, and CR23X. Doing otherwise
will connect the datalogger’s analog and power ground
planes to each other, which in some cases can cause
offsets on low-level analog measurements. To avoid 2 mA
flowing into analog ground, switch power on/off for its
measurement.
CAUTION
TABLE 7-1. Connections for Single-Ended Measurements
Color Description
CR1000,
CR3000,
CR800,
CR5000,
CR23X
CR10X
CR10,
CR510,
CR500
Brown Temperature
Signal
Single-Ended
Input
Single-Ended
Input
White Relative Humidity
Signal
Single-Ended
Input
Single-Ended
Input
Yellow Signal Reference AG
Gray Power Ground AG
Clear Shield G
Green Power 12V/*SW12V 12V/*SW12V
*CR10X Power Control if
using SW 12V
Jumper from
SW 12V
CTRL to
Control Port
12