Campbell Scientific HMP155A Temperature and Relative Humidity Probe - Manual (Page 16)

HMP155ATemperature and Relative Humidity Probe
current at 12 volts. Approximately 2 seconds is required for the sensor to
warm up after power is switched on. At measurement rates slower than once
per 5 seconds, the overall power consumption (datalogger and sensors) may be
reduced by switching power to the HMP155A. Most current Campbell
Scientific dataloggers have a built-in switched 12 volts that can be used to
control power.
HMP155 sensors purchased directly from Vaisala with serial
numbers < E4430001 require approximately 5 seconds warm up
time.
The CR9000, CR510, CR500, CR7, CR10, and 21X dataloggers do not have a
built-in switched 12 V. Users with these dataloggers can power the sensor
continuously or purchase the model SW12V to switch power.
The -L option on the model HMP155A Temperature and Relative Humidity
probe (HMP155A-L) indicates that the cable length is user specified. TABLE
5-1 gives the recommended lead length. Add 2 ft to the cable length if the
enclosure is mounted to the leg base of a CM106B, CM110, CM115, or
CM120 tripod.
TABLE 5-1. Recommended Lead Lengths
2 m Height Atop a tripod or tower via a 2 ft crossarm
Mast/Leg CM202 CM106B CM110 CM115 CM120 UT10 UT20 UT30
9 ft 11 ft 14 ft 14 ft 19 ft 24 ft 14 ft 24 ft 37 ft
The probe’s cable can terminate in:
• Pigtails that connect directly to a Campbell Scientific datalogger
(option –PT).
• Connector that attaches to a prewired enclosure (option –PW). Refer
to www.campbellsci.com/prewired-enclosures for more information.
6. Specifications
Features:
• Well-suited for long-term, unattended applications
• Accurate and rugged
• Compatible with Campbell Scientific CRBasic dataloggers:
CR200(X) series, CR800 series, CR1000, CR3000, CR5000, and
CR9000(X). Also compatible with Edlog dataloggers: CR500,
CR510, CR10(X), CR23X, 21X, and CR7
Operating temperature range
for humidity measurement: –80° to +60°C –112° to +140°F)
Storage temperature range: –80° to +60°C –112° to +140°F)
Electromagnetic compatibility: Complies with EMC standard EN61326-1,
Electrical equipment for measurement
NOTE
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