ACR SmartReader 2 4-Channel Relative Humidity & Temperature Data Logger from ACR Systems

The SmartReader 2 4-channel relative humidity & temperature data logger has a built-in temperature sensor, a plug-in relative humidity sensor and is equipped with two extra channels to connect either ACR's temperature/RH probe or thermistor probes. The RH plug-in sensor is field replaceable so you can always be assured of continuous recording. The SmartReader 2 is excellent for monitoring air quality conditions.


0 to 95% (non-condensing)
Better than 0.4% between 25 & 60% RH at 25° C (77° F)
+/- 4% RH from 10 to 90% (-20 to 40°C [-4 to 104°F])
Memory Size
32 KB
ACR EH-020A Temperature & RH Probe
ACR ET Series Temperature Probes
No. of Channels
Four (one for internal temperature sensor, one for internal RH sensor, one for optional external RH, and one for optional external temperature or resistance)
RH Sensor
Capacitive thin polymer film
Response Time
Adequate ventilation increases the response time which is approximately 5 minutes in still air
Environmental Conditions
Like all relative humidity sensors, when exposed to contaminants and/or extreme environmental conditions, accuracy degradation could result. For maximum long-term stability, sensor should not be exposed or subjected to organic solvents, corrosive agents (strong acids, SO2, H2SO4, CI2, HCl, H2S, etc.), and strong bases (compounds with PH greater than 7). Dust settling on the sensor surface will not affect sensor performance except possibly to decrease the speed of response.

Ordering Information

Model Memory Catalogue #
SR-002 32 KB 01-0025

More information

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2-channel temperature
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SmartReader 2
4-channel relative humidity & temperature data logger
SmartReader 3
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SmartReader 4
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SmartReader 5
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SmartReader 6
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SmartReader 7
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SmartReader 8
8-channel temperature
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SmartReader 9
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