8.2 Replace the temperature and humidity
element
Replace the temperature and humidity element every 1 to 2 years to ensure accurate
measurements. The element is pre-calibrated; so, changing the element will return the system to
factory calibration accuracy. A replacement filter cap is supplied with the element; fit it to ensure
adequate air flow to the sensor element.
To replace the element, the Wintersense SDI-12 unit must be brought down to ground level and
the outer hood removed as discussed in
(p. 17). The temperature and humidity
element is on the opposite end of the electronics box as the infrared sensor, which normally
points down to the road. Unscrew the filter cap in an anticlockwise direction, by hand, to expose
the sensor element.
Figure 8-1. Sensor element with filter cap on
Wintersense SDI-12
18
