GEO Calibration Hygro Mini is a portable humidity and temperature generator designed for professional calibration applications in the laboratory and directly in the field. Its compact design, battery-powered operation and simultaneous control of relative humidity and temperature make the Hygro Mini particularly suitable for mobile calibration tasks, service applications and hard-to-reach measurement locations.

The GEO Calibration Hygro Mini provides a controlled temperature range from 18 °C to 35 °C and a relative humidity range from 5 % RH to 85 % RH at 23 °C. With a specified relative humidity accuracy of ±1.0 % RH and temperature accuracy of ±0.4 °C, the instrument provides a compact solution for checking and calibrating humidity and temperature probes.

Unlike simple humidity comparison chambers, the Hygro Mini actively generates and controls both humidity and temperature. This allows defined calibration points to be created directly at the required location.

The compact construction is particularly beneficial for field calibration. According to GEO Calibration, the Hygro Mini was specifically designed as a portable humidity and temperature generator for field applications.

At europascal, you receive professional solutions for humidity and temperature calibration. We can assist you in selecting the appropriate humidity generator, reference sensor and accessories for your individual calibration application.

For regular calibration and metrological traceability of your humidity and temperature measuring equipment, europascal also provides a professional Calibration Service.

Your Benefits at a Glance

The GEO Calibration Hygro Mini combines controlled humidity and temperature generation with a compact design for mobile calibration applications.

• Portable humidity and temperature generator
• Designed for field calibration
• Relative humidity range from 5 % RH to 85 % RH at 23 °C
• Temperature range from 18 °C to 35 °C
• Relative humidity accuracy ±1.0 % RH
• Temperature accuracy ±0.4 °C
• PID control
• Temperature uniformity ±0.20 °C
• Humidity uniformity ±0.40 % RH
• Temperature stability 0.10 °C
• Humidity stability 0.15 % RH
• Simultaneous humidity and temperature control
• Battery-powered operation
• Compact and space-efficient design
• Suitable for hard-to-reach measurement locations
• Suitable for low-volume humidity probes
• Portable solution for laboratory and field calibration
• Orientation does not affect specified accuracy
• Designed for fast stabilization at programmed setpoints

Portable Humidity Calibration

One of the main advantages of the GEO Calibration Hygro Mini is its portability.

Conventional humidity calibration systems are often designed as stationary laboratory equipment. This means that humidity probes and measuring instruments need to be removed from the process and transported to the calibration laboratory.

The Hygro Mini follows a different approach.

Its compact dimensions and battery-powered design make it possible to bring the humidity generator directly to the measurement location.

This is particularly useful for service technicians, calibration laboratories and quality assurance departments that need to perform measurements at different locations.

Typical applications include:

• Calibration laboratories
• In-house calibration laboratories
• Quality assurance
• Measuring equipment monitoring
• Pharmaceutical industry
• Food industry
• Process industries
• Environmental monitoring
• HVAC applications
• Building automation
• Production environments
• Research and development
• Maintenance
• Mobile calibration services

Controlled Relative Humidity from 5 % to 85 % RH

The GEO Calibration Hygro Mini provides a controlled relative humidity range of:

5 % RH to 85 % RH at 23 °C

This enables humidity sensors to be checked at several defined calibration points across a wide range of typical industrial and laboratory applications.

Instead of checking a humidity sensor at only one ambient condition, users can generate multiple humidity levels.

For example, calibration points can be selected in the lower, medium and upper portions of the sensor’s working range.

This provides considerably more information about the measurement characteristics of the device under test.

Temperature Control from 18 °C to 35 °C

Relative humidity is strongly dependent on temperature.

For accurate humidity calibration, controlling only the water vapor content is therefore not sufficient. Temperature also needs to be controlled and monitored.

The GEO Calibration Hygro Mini provides a controlled temperature range from:

18 °C to 35 °C

This enables the calibration chamber to generate defined combinations of temperature and relative humidity.

The simultaneous control of these two parameters is one of the key advantages of a professional humidity generator compared with simpler humidity reference solutions.

Humidity Accuracy of ±1.0 % RH

The specified relative humidity accuracy of the GEO Calibration Hygro Mini is:

±1.0 % RH

This makes the instrument suitable for professional calibration and verification of numerous industrial humidity sensors and measuring instruments.

The required uncertainty of the complete calibration should always be considered separately and depends on the reference system, calibration method, environmental conditions and device under test.

For professional traceable calibration of your humidity measurement equipment, europascal provides its Calibration Service.

Temperature Accuracy of ±0.4 °C

In addition to humidity generation, the Hygro Mini controls the temperature within the calibration environment.

The specified temperature accuracy is:

±0.4 °C

This allows humidity sensors with integrated temperature measurement to be checked for both measured quantities using one portable calibration system.

This is particularly useful for combined relative humidity and temperature probes used in environmental monitoring, process measurement and HVAC systems.

PID-Controlled Calibration Environment

The GEO Calibration Hygro Mini uses a PID controller to maintain the selected temperature and humidity conditions.

PID control continuously evaluates the difference between the setpoint and actual condition and adjusts the system accordingly.

This enables stable calibration conditions to be maintained inside the measurement environment.

According to the available specifications, the system provides:

Temperature uniformity: ±0.20 °C

Humidity uniformity: ±0.40 % RH

Temperature stability: 0.10 °C

Humidity stability: 0.15 % RH

These characteristics are particularly important when comparing a device under test with a reference humidity and temperature sensor.

Designed for Field Calibration

The GEO Calibration Hygro Mini was specifically developed for field calibration.

Its compact dimensions allow it to be used in locations where larger humidity chambers would be impractical.

Typical examples include measurement points in production facilities, laboratories, service environments and technical installations.

Battery operation further increases flexibility because the instrument does not need to remain permanently connected to a mains power supply during mobile operation.

The compact design also makes transportation between different measurement locations easier.

Fast Setpoint Changes

Efficient calibration requires not only accurate control but also reasonable transition times between individual calibration points.

The Hygro Mini is designed to reach programmed humidity and temperature conditions quickly.

This is especially valuable when several calibration points need to be performed during a service visit.

Rather than waiting for a large environmental chamber to stabilize, the compact chamber volume of the Hygro Mini supports efficient changes between calibration conditions.

Actual stabilization time depends on factors including the selected temperature and humidity points, ambient conditions and the condition of the desiccant.

Humidity Generation System

To generate different relative humidity values, the GEO Calibration Hygro Mini uses an integrated humidity control system.

For humidification, the instrument uses distilled water.

For reducing humidity, a desiccant system removes moisture.

This combination enables the controller to increase or decrease the relative humidity according to the selected setpoint.

Correct maintenance of the water reservoir and desiccant is important for reliable operation.

Only the specified water quality should be used in accordance with the manufacturer’s instructions.

Ideal for Humidity Sensors and Probes

The GEO Calibration Hygro Mini is particularly suitable for checking and calibrating compact humidity probes.

Typical devices under test include:

• Relative humidity probes
• Humidity transmitters
• Combined humidity and temperature sensors
• Digital hygrometers
• Environmental monitoring sensors
• HVAC humidity sensors
• Data logger probes
• Process humidity sensors
• Laboratory humidity sensors

The compact measurement volume is especially advantageous for probe-type sensors that do not require a large environmental chamber.

Comparison Calibration

A typical humidity calibration can be performed as a comparison between the device under test and a suitable reference sensor.

Both sensors are exposed to the same controlled humidity and temperature conditions.

The Hygro Mini generates the required environmental condition and allows sufficient time for the reference and device under test to stabilize.

The readings can then be compared.

This procedure can be repeated at several relative humidity levels.

For example, a calibration sequence can contain low, medium and high humidity points depending on the operating range and calibration requirements of the device under test.

Temperature and Humidity Calibration in One System

Many modern environmental sensors measure both temperature and relative humidity.

Using separate systems for both quantities can make calibration unnecessarily complex.

The GEO Calibration Hygro Mini controls both temperature and humidity within one compact calibration environment.

This makes it possible to evaluate both measurement functions of a combined sensor without transferring the device between separate temperature and humidity calibration systems.

For mobile calibration in particular, this combination can significantly simplify the equipment required for a service assignment.

Technical Highlights

The GEO Calibration Hygro Mini provides a practical combination of portability, humidity generation and temperature control:

• Relative humidity range: 5 % to 85 % RH at 23 °C
• Temperature range: 18 °C to 35 °C
• Relative humidity accuracy: ±1.0 % RH
• Temperature accuracy: ±0.4 °C
• PID controller
• Temperature uniformity: ±0.20 °C
• Humidity uniformity: ±0.40 % RH
• Temperature stability: 0.10 °C
• Humidity stability: 0.15 % RH
• Typical temperature ramp rate: 1.00 °C/min
• Typical humidity ramp rate: 3.00 % RH/min
• Portable design
• Battery-powered operation
• Controlled humidity and temperature
• Designed for field calibration
• Suitable for low-volume probes

Technical Specifications

Hygro Mini for Mobile Calibration Services

For calibration service providers, portability is a significant advantage.

Humidity probes installed in monitoring systems or production environments are not always easy to remove.

The GEO Calibration Hygro Mini can be transported directly to the measurement location, enabling calibration equipment to be brought closer to the installed sensor.

This can reduce logistical effort and make field calibration considerably more efficient.

The instrument is therefore particularly useful for service organizations that regularly work at different customer locations.

Advantages over Simple Humidity References

Simple humidity references can provide useful fixed humidity conditions but often have limitations when multiple calibration points or controlled temperature conditions are required.

The GEO Calibration Hygro Mini actively controls both humidity and temperature.

This provides considerably more flexibility when a calibration procedure requires several humidity setpoints.

Users can select different conditions without replacing individual fixed-humidity references for every measurement point.

Active temperature control also provides improved control over one of the most important influencing quantities in relative humidity measurement.

Why Choose the GEO Calibration Hygro Mini?

The GEO Calibration Hygro Mini combines portability, controlled humidity generation and temperature control in one compact instrument.

Its 5 % RH to 85 % RH range at 23 °C covers a large proportion of typical humidity calibration applications.

A specified humidity accuracy of ±1.0 % RH supports professional comparison measurements, while the temperature range from 18 °C to 35 °C enables combined humidity and temperature calibration.

Battery-powered operation and compact dimensions make the system particularly attractive for mobile calibration and service applications.

The Hygro Mini is therefore a practical solution for calibration laboratories, quality assurance departments and service technicians requiring a portable humidity calibration system.

At europascal, we can assist you in selecting the appropriate GEO Calibration humidity generator, reference sensor and accessories for your individual application.

For regular calibration and metrological traceability of humidity sensors, hygrometers, temperature sensors and humidity calibration equipment, use the europascal Calibration Service.

Additional measurement and calibration solutions are available through the europascal English homepage.

Discover more GEO Calibration products here.

Manufacturer information about the GEO Calibration Hygro Mini is available on the GEO Calibration website.

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