Testing operation - WMT700

WMT700 Series User Guide

Document code
M211095EN
Revision
K
Language
English
Product
WMT700
Document type
User guide
Optional verifier (WMT70VERIFIER)

WMT700 measures the time it takes for an ultrasonic signal to travel from one transducer to another. Therefore, the accuracy of the sensor depends on the distance between the transducers and the time-of-flight measurement circuit, which uses a crystal oscillator for its time reference.

If necessary, you can verify the distance between the transducer arms with an optional verifier. You can order the verifier from Vaisala as an accessory.

Vaisala recommends that you test the proper operation once a year or if you suspect that the transducers may have been damaged. You can perform the test either in the field or in a laboratory.

CAUTION Do not perform the test when the wind speed is more than 10 m/s (22 mph) or when there is a risk of thunderstorm in the area.
Some random data samples may be lost during the verifier test. This does not indicate that sensor or instrument is faulty.
The verifier cannot be used to test the accuracy of wind direction measurement. During zero wind calibration, the wind direction data is missing. This does not indicate that the sensor is faulty.
Disable heating before performing the verifier test.

To disable heating, disconnect the heater supply voltage or set the heaterOn parameter to 0.

  1. Slip the verifier over the 3 transducers.
  2. Start wind measurement.

    The command depends on the selected communication profile.

  3. Make sure that WMT700 reads less than 0.22 m/s (0.5 mph) with the verifier in place.
  4. Remove the verifier.