To calibrate the rain gauge you need:
- assembled rain gauge with double spoon, magnet, bridge, set screws and metal plate
- a ring wrench no 7
- rain bucket
- Calibration tool - KNF SIMDOS 10 Diaphragm Metering Pump
- destilled water
- a thread-lock fluid to secure the set screws
Make sure that the rain bucket is levelled and that the double spoon is moving easily when it is tipping sideways
Set the metering pump to 4ml in 6 seconds. Please check the metering pump if it measures the Milliliter (ml) correct before calibrating.
- Start with the left side - this means left side of the double spoon is up.
- Press start at the metering Pump (red square below)
- If the left spoon doesn't empty itself, the right set screw has to be set higher
- If the left spoon empty itself before 4ml are in it, the right screw has to be set lower
- Try until the left spoon empties itself when its full with 4ml and no drop drops into the right spoon.
- 1 drop of water is approximately a 1/4 turn of the set screw.
- After each try, dry the left spoon with a cloth, so that the result doesn't get adulterated and is for sure correct.
- Start with the right side - this means right side of the double spoon is up.
- Press start at the metering Pump
- If the right spoon doesn't empty itself, the left set screw has to be set higher
- If the right spoon empty itself before 4ml are in it, the left screw has to be set lower
- Try until the right spoon empties itself when its full with 4ml and no drop drops into the left spoon.
- 1 drop of water is approximately a 1/4 turn of the set screw.
- After each try, dry the right spoon with a cloth, so that the result doesn't get adulterated and is for sure correct.
- Pleas check both sides of the double spoon after each other again to be sure its correct, otherwise readjust the side which is not correct.
- When both sides of the double spoon are correct secure the set screw with a thread-lock fluid and let it dry
- Take your time the whole process takes at least 20min.