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Show APPENDIX C ANALOG WIND SYSTEM INSTALLATION AND CALIBRATION Tower and Instrument Support for Wind System The tower should be of sufficient height to get anemometer and vane at least 30 feet above mean maximum snow depth at the site. ( See discussion in text about site selection.) A sectional TV tower, such as the Rohn Series 25 ( A37) is satisfactory for most sites. The instrument supports, mounted on top of the tower, must be assembled locally from 1- 5/ 8" galvanized pipe and fittings. Be sure to use double- weight pipe; ordinary single-weight water pipe has not proven to be durable for this support. Details and exact dimensions are not critical; see Figure 16 for general configuration. Equipment Required: 1. Wind speed transmitter ( cups and base). ( Wind Speed indicator Model F420- C). 2. Wind direction transmitter ( vane and base). 3. Twin- channel recorder. ( Esterline Angus Model A602C) . 4. Power supply calibration unit ( see below under Calibration). 5. Adequate cable ( at least 5 conductors, no smaller than AWG 19, external shield, or metal sheath if buried underground) laid from wind sensor site to the recording site with junction boxes, plus reserve cable to replace longest piece in the line in case of failure. 6. Rohn tower, base and guy wires ( see A37)• 7. Instrument support for anemometer and vane assembled from pipe fittings. 8. Properly prepared cement base with 4 bolts on which to attach the hinged base plate for the tower. 9. Multi- meter with scales 0- 50K ohms, 0- 6 volts D. C. ( B7c) 10. A voltage divider ( anemometer calibrator) with output from 0 to 4 volts. See below and Figure 17- 66 |