TWP/SMET/C2 - Induced wind speed when calm

The upper and lower wind sensors were not trending well at wind speed below 1 m/s.  Both 
sensors were showing values above 0m/s when calm.  The lightning protector was at fault 
resulting in an induced wind voltage during calm conditions.

Users should subtract any offset found (for example 0.19 m/s for upper wind speed) when 
the wind speeds are flat-lined.  The offset value was not consistent.

• up_spd_max
• lo_spd_min
• up_spd_arith_avg
• up_spd_vec_avg
• lo_spd_arith_avg
• up_spd_min
• lo_spd_vec_avg
• lo_spd_max