What are the steps to perform a field calibration check on a TB4-L, a TB4MM-L, or a CS700-L?
Remove the housing assembly from the base by removing the three screws and lifting upward on the housing.
Check the bubble level to verify the rain gage is level.
Pour water through the inner funnel to wet the two bucket surfaces. Using a graduated cylinder, slowly pour 314 cc (19.16 in3) of water, over a 15 minute period, into the collection funnel. This volume of water is equal to 0.39 inches of rainfall (10 mm).
After the water has passed through the rain gage, the tipping bucket should have tipped 39 times for the TB4-L or CS700-L, or 50 times for the TB4MM-L.
If the rain gage fails to record the correct number of tips, return the unit to Campbell Scientific for recalibration.