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Michell Instruments

S904 Humidity Calibrator

Stand-alone & transportable RH calibrator, chamber features 5 interchangeable ports to accommodate any RH sensor

Have questions? We're here to help!
Have questions? We're here to help!

The S904 is a completely stand-alone and transportable humidity calibrator, requiring no external services other than mains power. The calibration chamber features 5 interchangeable ports to accommodate virtually any brand, type or model of humidity sensor. This calibrator is ideal for companies or organizations looking to calibrate large numbers of probes in a laboratory or field setting.

• Simple operation and maintenance
• Easy calibration of relative humidity sensors
• Excellent chamber stability and uniformity
• Manual control or optional straightforward automated set point programming
• Optional in-built data-logging for reference probe and probes under calibration
• Humidity and temperature controlled chamber
• Generate 10 to 90% RH over +10 to +50°C (+50 to +122°F) temperature
• Transportable to allow on-site calibrations

HumidityGeneration Range: 10-90% RH

Accuracy: ≤±1% RH (10–70% RH)

Control Element: ≤±1.5% RH (70–90% RH)

Stability: ±0.2% RH (20–80% RH)
TemperatureGeneration Range: +10 to +50°C (+50 to +122°F)
(Lowest T set point = 10°C (18°F) below ambient

Accuracy: ±0.1°C (±0.2°F)

Stability: ±0.1°C (±0.2°F)
ChamberRamp Rate from:
+20 to +40°C (+68 to +104°F) 1.5°C/minute (2.7°F / minute)
+40 to +20°C (+104 to +68°F) 0.7°C minute (1.2°F / minute)

Control Element: Removable relative humidity sensor
GeneralProbe Ports: Up to 5 – sensor body diameters 5 to 25mm (0.2 to 0.98") accommodated by port adapters

Chamber Volume: 2000cm³ (122.1in³)

Chamber Dimensions: 105 x 105 x 160mm (4.13 x 4.13 x 6.3") (h x w x d)

Instrument Dimensions: 290 x 520 x 420mm (11.4 x 20.5 x 16.5") (h x w x d)

Set Point Resolution: 0.1 for humidity and temperature

Displays: 3 digit LED, 10mm (0.39") characters

Supply: 85 to 264 V AC, 47/63 Hz, 150 V A

Weight: 20kg (44lbs)

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