Chapter 4 _______________________________________________________________ InstallationVAISALA _______________________________________________________________________ 67WARNING Using a long cable between different units (sensors, transmitters, powersupplies, and displays) can cause a lethal surge voltage if a lightningstrike occurs in the vicinity. Always apply proper grounding proceduresand follow the requirements of the local Electrical Code.Aligning Ultrasonic Wind Sensor WMT703WMT703 is permanently marked with the letter N and a north arrow.WMT703 needs to be aligned in such a way that this arrow points to thenorth. Misaligning WMT703 causes a wind direction offset error in themeasurement results, as shown in Figure 30 on page 68.To align WMT703, proceed as follows:1. Determine whether the array of WMT703 is correctly aligned witha compass or other similar method.2. If the alignment is not correct, readjust the orientation: rotate theFIX70 mounting kit so that the north arrow and the northtransducer point to the north in the measurement location. Do notremove WMT703 from the mounting kit during the alignmentprocess. Tighten the bolts of the FIX70 mounting kit.Figure 29 below and Figure 30 on page 68 show the correct alignmentand the measurement error caused by misalignment of WMT703.0208-025Figure 29 Correctly Aligned WMT703
