Anemometers and Windvanes in action!
Windspeed Ltd (Vector Instruments), 113 Marsh Road, RHYL, N. Wales, LL18 2AB, United Kingdom.
Windspeed Limited
Click for info on: Wind Speed sensors Click for info on: Wind Direction Sensors Click for info on: Masts + Mountings Click for info on: Air Temperature sensors Click for info on: Masts + Mountings Anemometer, Windvane and Air Temperature sensors
 Monday, July 22 2024  Home [arrow]  Calibration [arrow]  MEASNET / IEC Search site:  

Latest Weather...
(Rhyl, N.Wales, UK)
Wind Speed:  3.6 mph
Wind Direction:  231 °
Air Temp.:  15.5 °C
Rel. Humidity:  90.9 %
Rain (last Hr):  0.0 mm
(updated at: 21:03 UTC)

Please call/email us if you need:

Translate using Google:

This website requires Javascript and Cookies to be enabled for correct operation. Privacy Policy...

Use subject to Terms & Conditions.

GDPR: to request or decline communications containing marketing, news & updates from us, click HERE.
Celebrating more than 50 years manufacturing & servicing High Quality Vector Instruments Anemometers and Windvanes at Windspeed Ltd
Anemometer Specification/Classification and Calibration (MEASNET / IEC61400-12-1 / IEC61400-50-1)
Vector Instruments' A100L2, A100AC and A100LK/A100LM anemometers are among the very few available having Class 1 performance ("First Class") according to the requirements of IEC and MEASNET standards.

The outline and mechanical design remains unchanged since the introduction of the Porton™ Anemometer in 1972, the electronics being continuously developed during this time to provide a well tried and reliable product.

Anemometers have, until recent years, only been calibrated/evaluated in wind tunnels. Investigation by the wind power industry has found that various anemometer designs behave differently in field conditions where there is considerable turbulence. The Vector Instruments A100 design is one of a very few which has been subjected to field trials, and these have shown that Vector Instruments' A100L2, A100AC, A100LK, A100K and A100LM anemometers (using the R30/K2, R30/K and R30/M3 rotors) are amongst the very few cup anemometer designs which can be classified as having "First Class" performance according to the requirements of the IEC61400-12-1(Ed.1) when suitably sited/mounted and operated. This high performance classification means that measurements are accurate in the actual wind conditions experienced in the field (as opposed to just being accurate in the artificial conditions of a low-turbulence wind tunnel) making them the clear choice for wind assessment applications.

The results of field trials and wind-tunnel tests performed for us have shown that the A100L2 and A100LK/A100LM anemometers can be classified as "Class 1.7S" according to IEC61400-12-1 (Ed.1) when suitably sited and operated.

The A100R/K is a variant of the "standard A100R" which is fitted with the same "R30/K" rotor type as used on the A100LK... this A100R/K variant also has First Class performance.

For IEC61400-12-1 (Ed.1), the A100 series cup anemometer achieves "Class 1.0" performance under certain special conditions ("Class S" conditions, see the independent certification document which is available detailing this), however the A100 series also performs well in the standard "Class A" and "Class B" conditions. The report from the independent ACCUWIND project indicates that the A100 series can be classified as 1.8 for "Class A" conditions, and 4.5 for "Class B" conditions which is amongst the best (i.e. "Class 1.8A" and "Class 4.5B")

Note that the IEC 61400-12-1 standard has been revised (2022) and the content of Annexes F, G, I, J (which details anemometer calibration, classification, mounting and assessment) have now been moved to a new separate standard IEC 61400-50-1, however the content moved to the new IEC 61400-50-1 standard is essentially the same as the original IEC61400-12-1 standard annexes.

** Development and testing work is currently in progress on an updated A100 series anemometer which will fully meet the requirements of the recent IEC61400-12-1 & IEC61400-50-1 standard updates. As we understand it, the most significant changes for cup anemometers in the updated standards relate to 'asymmetry' of the anemometer's directional response - some regular users have told us that whilst our current A100 anemometer model with Ed.1 certification has a small physical asymmetry at the bottom end due to the cable-exit on one side of the base-plate, they believe that the effects of the mounting/booms and/or 'tower wake/shadow' are much more significant in most installations. The updated product will have a symmetrical design as well as additional improvements to performance. (expected to be available mid/late 2024) **

See also:

MEASNET describes itself as an "International Network for Harmonised and Recognised Measurements in Wind Energy" and is an organisation of test/calibration facilities which are able to calibrate anemometers according to a common standard which is specifically aimed at Wind Power applications where the anemometers are to be used to survey a site in order to forecast the amount of wind power which might be generated should a wind turbine be erected on that site.

The anemometer calibration setup/procedure specified in the IEC61400-12-1 standard is essentially identical to the older MEASNET calibration standard, therefore "IEC61400-12-1 calibrations" performed by non-MEASNET members using a reputable ISO17025 certified high-quality wind tunnel with appropriate size/characteristics should now be equivalent to a MEASNET calibration.

We are able to arrange for calibrations in MEASNET wind tunnels and supply our anemometers with individual MEASNET calibration certificates if required.

The latest IEC standard also includes a procedure for calibrating windvanes, such as our W200P, and we can also arrange to supply W200P windvanes with IEC/MEASNET calibration certificates if required.

A100LK/PC3 and A100R/K First Class Anemometers are now usually available from our stock WITH A MEASNET CALIBRATION CERTIFICATE and can be delivered to you quickly. These are packaged as our "/PRO Bundles" and also include a 6M cable, standard 405 mounting adaptor (for 1inch pole) and a "cable jointing kit" (to permit easy addition of extra cable if necessary).
Please contact us for more information on availability and prices of these "/PRO Bundles".

[Last Revised: Oct 2013]

Windspeed Ltd (Vector Instruments)
Windspeed Limited (trading as Vector Instruments),
113 Marsh Road, RHYL, North Wales, LL18 2AB, United Kingdom
Tel: +44 (0) 1745 350700
Website design and content is copyright (c) 2003-2024 Windspeed Limited (unless otherise stated). All trademarks are acknowledged.