3 communications considerations, 1 direct communications, 1 cable lengths – Campbell Scientific TurfWeather Weather Station User Manual

Page 22: 2 grounding issues, Communications considerations, Direct communications, Cable lengths, Grounding issues, 1. example of ten times the height rule, Figure 5-1

Advertising
background image

TurfWeather Weather Station

FIGURE 5-1. Example of Ten Times the Height Rule

Another option when obstructions exist is to raise the weather station height

above the obstruction by using mast extensions.

a. If your weather station will be inside a fence to discourage

vandalism, the fence top must be lower than the wind sensors even

if the fence is chain-link.

b. Accurate wind measurements require your weather station to

be located at the highest point in a particular region.

c. The tripod/mast height cannot exceed 312 cm (10 ft).

5.3 Communications Considerations

5.3.1 Direct Communications

Short haul modems enable communication between the weather station and

computer over two twisted pairs of wires. This communication requires the

DCE/DTE switch on the modem to be in the DTE position at the weather

station, and in the DCE position at the computer.

5.3.1.1 Cable Lengths

The maximum distance between modems is determined by baud rate and wire

gage. At 9600 bps, the approximate range is 3.2 km (2 miles) using 24 AWG

wire.

5.3.1.2 Grounding Issues

Outdoor cables may be subject to induced currents due to lightning or other

environmental factors. Therefore, proper grounding is imperative to avoid

NOTE

12

Advertising