Calibrating the rain gauge on your AcuRite Iris (5-in-1) weather sensor ensures accurate rainfall measurements. Here's how to do it:
- Level the Sensor: First, make sure your AcuRite Iris sensor is perfectly level using the built-in bubble level. This is crucial for accurate readings.
- Monitor Rainfall: Use a compatible display unit or the AcuRite software to monitor the rainfall during calibration.
- Simulate Rainfall: Take a plastic cup and make a small pinhole in the bottom. Hold the cup over the rain gauge and slowly pour exactly 1 cup (8oz) of water into it, allowing the water to drip into the gauge.
- Observe Tipping and Reading: You should hear the internal buckets tip, and water should drain through the rain gauge. Your display unit should register the rainfall in approximately 0.01" increments shortly after each tip.
- Timing is Key: The cup of water should take more than 20 minutes to empty. This simulates a normal, steady rainfall.
- Verify the Reading: When the cup is empty, your display unit should ideally register 1.06". If the reading is off, you'll need to make adjustments.
Calibration Tips:
- Bucket Tipping: Aim for an equal number of water drops between bucket tips (about 25 drops). If the drops are uneven, adjust the calibration screws on the bottom of the AcuRite Iris sensor until the tipping is balanced.
- Adjusting the Reading: To adjust the rainfall reading, make equal adjustments to both calibration screws on the bottom of the sensor. Turning the screws clockwise increases the rainfall reading, while turning them counterclockwise decreases it.
- To adjust by 2%, turn both screws 1/8 of a turn.
- To adjust by 4%, turn both screws 1/4 of a turn.
- To adjust by 8%, turn both screws 1/2 a turn.
For detailed illustrations and further information, consult the instruction manual that came with your AcuRite Iris weather sensor.