Anemometer Calibration

Calibration is crucial for ensuring measurement accuracy and data integrity. An uncalibrated anemometer can provide false wind speed and direction data, leading to poor decision-making. This is critical for:

• Safety: In aviation, firefighting, and industrial operations where wind conditions are a direct safety factor.
• Regulatory Compliance: Meeting standards for environmental monitoring, HVAC system performance, and workplace safety.
• Financial Accuracy: In wind energy, inaccurate data can lead to significant revenue miscalculations.
• Research Validity: Ensuring the credibility of scientific and meteorological studies.

The calibration interval depends on the instrument’s usage, environment, and required accuracy. A general rule of thumb is annually. However, we recommend more frequent calibration (e.g., every 6 months) if the anemometer is:

• Used in harsh environments (e.g., marine, industrial, or dusty areas).
• Subject to mechanical shock or extreme weather events.
• Used for critical applications where data accuracy is legally or financially mandated.

Our standard turnaround time is 5-8 business days upon receipt of your instrument. We offer expedited services (e.g., 2-3 business days) for urgent needs, which may incur an additional fee. The time includes inspection, cleaning, calibration, and certification.

You will receive a comprehensive Calibration Certificate that includes:

• Calibration data.
• The measurement uncertainty.
• A statement of traceability.
• The standards and equipment used.
• Any “As Found” deviations if the instrument was out of tolerance.

 If we find your anemometer is outside its specified accuracy, we will contact you immediately before proceeding. We will issue customer notification form and recommend one of two options:

1. No Adjustment: We can issue a certificate with the “As Found” data only ,( and customer notification form )documenting its performance without making changes.
2. Adjustment/Repair by manufacturer: we will issue the report of the performance of your anemometer and you may proceed to submit the report to the manufacturer or supplier of the item so as they can do adjustment and repair for it.

This is a core methodological question.

• Wind Tunnel: A controlled apparatus that generates a stable, uniform, and known wind speed in a test section. The device under test (your anemometer) is placed inside, and its readings are compared against the tunnel’s reference standard (which is itself traceable to a primary standard). This is the most common and controlled method for laboratory-grade calibrations.
• Reference Anemometer (Field Comparison): This involves mounting your anemometer alongside a pre-calibrated, higher-accuracy reference anemometer in the field. Both are exposed to the same natural wind, and their readings are compared. This method is less controlled but useful for verifying systems that are difficult to remove.

Measurement uncertainty is a quantitative indication of the quality of the calibration result. It is not an error, but a parameter that characterizes the range of values within which the true value of the measurement is believed to lie, with a stated level of confidence (usually 95%). A smaller uncertainty value indicates a higher-confidence calibration. It accounts for all potential sources of error in the calibration chain, from the reference standard to environmental factors.

Yes, our lab should be able to handle various types except ultrasonic anemometers. The method may differ:

• Cup /Vane Anemometers: Calibrated in a wind tunnel for speed and (for vanes) direction.
• Hot-Wire Anemometers: Require a stable, low-turbulence wind tunnel due to their sensitivity and fast response.

Proper installation is key to preserving calibration integrity. Follow these guidelines:

• Location: Install in a location with unobstructed airflow, away from buildings, trees, or other structures that create turbulence. The general rule is at a height of 10 meters above any obstacle within a 100-meter radius.
• Mounting: Use a sturdy, vibration-free mast. Ensure the anemometer is perfectly level (using a spirit level).
• Orientation: For directional vanes, align to True North (not Magnetic North) using a GPS or precise compass, accounting for magnetic declination.
• Cabling: Secure all cables to prevent wind-induced vibration or damage.