RM Young Wind Monitor on Symphonie #40 channel?

[Julia Austin]

A customer recently realized he had connected an RM Young Wind Monitor to one of Symphonie's built-in #40 anemometer channels instead of connecting it to channel 4, 5, or 6 using a Wind Monitor SCM.  He wondered how this would affect his measurements.

While this configuration is not recommended, the data themselves may be OK. 

The difference between the Wind Monitor SCM and the built-in channels is that the 05103 has a maximum frequency much higher than the maximum frequency of a #40C anemometer, so the filter on the SCM is set to a much higher frequency to ensure that it does not attenuate the signal too much at the high end of the wind speed range.  The #40 channels don't expect to see frequencies much above 80 Hz (corresponding to wind speed around 60 m/s).  The 05103 would be putting out over 600 Hz at that speed.  The filter would knock down the amplitude a lot, but the amplitude is pretty high to start with on that generator.

For wind speeds below 8 m/s, the data will certainly be fine.  Only high wind speeds might be reading artificially low.  It depends on the (unspecified) actual amplitude of the signal from that particular sensor.  To be absolutely sure measurements of higher wind speeds will be correct, try spinning the 05103 at a known wind speed and verifying that the wind speed being detected by the logger is correct.