METER ATMOS 41 - 3.6 TEMPERATURE SENSOR

16
SYSTEM
3.5 RAIN GAUGE
The ATMOS41 contains a 9.31-cm diameter rain gauge. During rain events, the flared hole
(Figure9) forms the rain into drops that pass by the drip counter. The spring (Figure9) acts
as a filter to keep out large particles but still allows enough flow so water does not back
up. Gold pins (Figure9) measure each drop of rain. Because the flared hole forms a drop of
a known size, the ATMOS41 counts the drops and calculate the water volume. As the rain
intensity increases, the drops become smaller, but the ATMOS41 firmware contains an
algorithm to automatically compensate for drop size as the rain increases.
When powered on, the ATMOS41 counts water drops continuously and adds each drop to an
accumulated total. When queried, the ATMOS41 outputs the total rainfall (in millimeters)
that has accumulated since the last query. Precipitation maximum intensity calculation is
capped at 280 mm/h, available from METER data loggers and software.
IMPORTANT: The ATMOS41 must be within approximately ±2 degrees of dead level (0, 0) in both the X and Y directions
to accurately measure rainfall. If not within this range, drops from the flared hole can miss the gold electrodes entirely.
Spring
Flared hole
Gold electrodes
Figure9 Rain gauge
The rain gauge locks in place using two pegs on the side of the rain gauge funnel. Follow the
steps below to get inside the rain gauge.
1. Line up the lock/unlock graphic located on the side of the rain gauge funnel with the
notch on the interface plate.
2. Press the rain gauge funnel down against the spring and turn counter clockwise until it
clicks in place.
ATTENTION: UNPLUG THE PYRANOMETER CONNECTOR INSIDE THE FUNNEL BEFORE FULLY REMOVING THE
FUNNEL.