It is specifically engineered to measure the moisture content of hay, straw, and various grains using the electrical resistance method.
1. Key Specifications (2026 Model)
|
Feature |
Specification |
|
Measuring Range |
0% – 80% |
|
Accuracy |
$\pm 0.5\%n$ |
|
Resolution |
0.1 |
|
Probe Length |
Standard 280mm (Optional 500mm for deep bales) |
|
Display |
4-digit LCD with Backlight |
|
Power Supply |
4 x 1.5V AAA Batteries |
|
Operation |
Electrical Resistance Method |
2. Best Use Cases
The HD100 is a "jack-of-all-trades" tool for farmers and ranchers. It features specific calibrations for:
- Baled Hay: Inserting the probe deep into large or small square bales to check for heat/fire risk.
- Loose Hay/Forage: Testing windrows before baling to determine if the hay is "cured" enough.
- Grains & Seeds: Checking wheat, corn, soybeans, paddy, and rice.
- Fiber Materials: Also used for straw, bran, and even some traditional herbal medicines.
3. Smart Features & Design
- Automatic Temperature Compensation (ATC): A critical 2026 feature that adjusts the moisture reading based on the temperature of the hay, ensuring accuracy even if testing in the hot afternoon sun or cold morning air.
- Alarm Function: You can set a moisture threshold; the meter will alert you if the reading exceeds your "safe" limit (e.g., 18% for small square bales).
- Voice Announcement (Certain Versions): Some high-end HD100 units now include a voice-out function that reads the measurement aloud—useful when you are balanced on a hay stack and can't easily see the screen.
4. Pro Tips for Accurate Hay Testing
Because the HD100 uses resistance, its readings can be influenced by how you use it:
- Bale Density Matters: Tighter bales will show slightly higher moisture than loose ones because of the contact pressure on the probes.
- Test the "Core": Always insert the probe at least 15–20cm into the bale. Surface moisture (dew) is often much lower than the internal moisture that causes mold.
- Multiple Samples: Never rely on one reading. Test 5–10 different spots in a stack or windrow and take the average.
5. Maintenance
- Probe Cleaning: Keep the steel needles clean and dry. Oily residue from certain crops can create an insulating layer that "tricks" the sensor into showing lower moisture.
- Calibration Check: Before the harvest season, check the meter against a known standard or a fresh bale you know is dry to ensure the sensors haven't drifted.