Air Temperature and Relative Humidity Sensor
The EE181 is a rugged, accurate air temperature and relative humidity (RH) probe that is ideal for long-term, unattended applications. It includes a proprietary coating on the RH element that increases the life of the element and protects it from dirt, dust, salt, or other contaminants. A 1000 Ω PRT measures air temperature for the -40° to +60°C range. For optimum results, the EE181 should be recalibrated annually.
Benefits and Features
- Well-suited for long-term, unattended applications
- Accurate, rugged, reliable
- Outstanding long-term stability
- Wide operating temperature range
- User cleanable
- Compact and easily interchangeable
- Low power consumption
- Compatible with most Campbell Scientific dataloggers
Specifications
Supply Voltage | 7 to 30 Vdc (typically powered by the datalogger’s 12 V supply) |
Average Current Consumption | < 1.2 mA |
Filter Description | 30 μm pore size, stainless-steel mesh |
Startup Time | 2 s |
Housing Body Material | Plastic |
Housing Classification | IP65 |
Sensor Diameter | 2.1 cm (0.83 in.) |
Length | 16.0 cm (6.3 in.) |
Weight | 290 g (10.2 oz) with 5 m cable |
Air Temperature | |
Sensor | 1000 Ω Platinum Resistance Thermometer (PRT) |
Operating Temperature Range | -40° to +60°C |
Storage Temperature Range | -40° to +80°C |
Output Signal Range | 0 to 1 Vdc |
Accuracy | ±0.2°C (at +23°C) |
Relative Humidity | |
Sensor | Capacitance |
Measurement Range | 0 to 100% RH (non-condensing) |
Output Signal Range | 0 to 1 Vdc |
Temperature Dependence | Typically 0.03% RH/°C |
-NOTE- | Accuracy specifications include hysteresis, non-linearity, and repeatability. |
Accuracy at -15° to +40°C |
|
Accuracy at -25° to +60°C | ± (1.4 + 0.01 • RH reading) % RH |
Accuracy at -40° to +60°C | ± (1.5 + 0.015 • RH reading) % RH |
Compatibility
Sensor Mounts
When exposed to sunlight, the EE181 must be housed in a 10-plate solar radiation shield. Campbell Scientific recommends the MetSpec RAD10E, which uses a double-louvered design that offers improved sensor protection from driving rain, snow, and insect intrusion. This shield also has lower self-heating in bright sunlight combined with higher temperatures (> 24°C [~75°F]) and low wind speeds (< 2 m s-1 [~4.5 mph]), giving a better measurement.
The EE181 will work with R. M. Young 10-plate radiation shields (41003-5 or 41003-5A), but these shields require a special adapter (pn 28415) to accommodate the sensor girth.
The RAD10E and 41003-5 attach to a crossarm, mast, or user-supplied pipe with a 2.5 to 5.3 cm (1.0 to 2.1 in.) outer diameter. The 41003-5A radiation shield attaches to a CM500-series pole or a user-supplied pole with a 5.1 cm (2.4 in.) outer diameter.