OptiCal Humidity Calibrator

The OptiCal is a bench-top, fully self-contained humidity/ temperature calibrator. The system comprises a humidity and temperature controlled chamber that can house up to five or more humidity sensors, depending on their physical dimensions. The humidity and temperature within the chamber are closed-loop controlled and continuously monitored by a precision chilled mirror reference hygrometer.

The OptiCal works by time proportioning the flows of dry and saturated air according to the pre-selected relative humidity value. The chamber temperature is controlled by a four-zone Peltier heat pump arrangement for maximum stability and minimum temperature gradient. The saturator assembly can be filled easily with the distilled water reservoir at the front of the unit and the easily accessible desiccator can be re-charged by heating when required. No other maintenance is necessary. The only external service required is a single phase power supply.

Product Features

  • Precision relative humidity and temperature calibrator
  • Generate 10 to 90% RH over +10 to +50°C (+50 to +122°F) temperature
  • Integral chilled mirror reference hygrometer
  • UKAS accredited calibration, as standard
  • Humidity and temperature profile generation for unattended verification of sensors
  • Transportable to allow on-site calibrations

Technical Specifications

Generated Range 10 - 90% RH
Control Element Accuracy ≤ ±1% RH (10-70% RH)
≤ ±1.5% RH (70-90% RH)
Stability ±0.2% RH (20-80% RH)
Generated Range +10 to +50°C (+50 to +122°F)
Accuracy ±0.1°C (±0.18°F)
Accuracy ±0.1°C (±0.18°F)
Ramp Rate +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
Accuracy Dew Point: ±0.2°C (±0.36°F)
Temperature: ±0.1°C (±0.18°F)
Measurement Units Dew Point: (°C/°F), % RH
Temperature: (°C/°F), gm-3, gkg-1, water activity (aW)
Outputs Analog: 4-20 mA or 0-20 mA over user-settable output
Accuracy: ±0.2°C (±3.6°F)
Digital: 500 Ω maximum load resistance
Alarm: RS232 @ 9600 baud rate
Volt free contact, 30 V, 100 mA maximum
Probe Ports Up to 5 - sensor body diameters 5 to 25mm (0.2 to 0.98") accommodated by port adapters
Chamber Volume 2000cm3 (112.1in3)
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 2 line Vacuum Fluorescent Display
Supply 85 to 264 V AC, 47/63 Hz, 150 V A
Weight 20kg (44lbs)



Related Products

Calibration Instruments

S904 S904
The S904 is a stand-alone and transportable humidity calibrator, for dew-point and relative humidity sensors.
HG10 HG10
The HG-10 is an automatic temperature and humidity calibration system with a wide humidity generation range.

Chilled Mirror Reference Instruments

Optidew Optidew
The Optidew is Michell Instruments’ high performance industrial chilled mirror hygrometer supplied in a rugged IP66, NEMA4 wall-mount enclosure.
S8000 Remote S8000 Remote
The S8000 Remote provides accurate measurement of dew-point, temperature and relative humidity and is designed for environmental monitoring.