So you’ve probably just heard about grain moisture meters and you are wondering how exactly it works. How it’s able to detect the moisture content of grains. Well, that’s exactly what this article is about.
What is a moisture meter?
Moisture meters are technological devices that detect or determine the amount of water in an object. The moisture meters measure water content in percentages. Objects whose water content is measured with moisture meters include wood, paper, soil, even air and that proves that anything can be measured for its water content.
However, there are specific moisture meters for each object or thing that has to be measured for its water content. And that of grains is called a grain moisture meter. Here is how to choose the right grain moisture meter for your needs
Generally, moisture meters work quite differently from each other as there are types. There two types of moisture meters and these are;
- Pin Meters: these have two metal probes called pins. They work when pins are inserted into the object and through the water in the object measures the resistance encountered by any electrical current running between the pins. The more moisture there is the less electrical resistance.
- Pinless Meters: these have electromagnetic sensor pads. They work using an electromagnetic signal and are sensitive to variations in the object being measured. They don’t cause damage to the object as there is no need to insert pins.
Grain Moisture Meters
Grain moisture meters, like all moisture meters, are calibrated instruments and these calibrations can appear differently based on the type of grain moisture meter. They also come with indicator scales and colors that indicate the moisture meter in percentage and determine whether an object is dry, intermediate, or wet respectively. Grain moisture meters are made in either analog or digital kinds.
Grain moisture meters like all moisture meters also come in two types; the pin meters and the pinless meters.
The GrainMate Moisture meter
An example of a grain moisture meter is the GrainMate GM-101 made by Sesi Technologies. It is a pin grain moisture meter and uses a single probe to determine the moisture levels of grains. It also has a crystal display that shows relevant information such as the moisture percent. It has five indicators;
- temperature indicator that indicates the current temperature around the grain
- a relative humidity indicator that indicates the current relative humidity around the grain
- a moisture content indicator that indicates the current moisture reading
- a selected grain indicator that indicates the crop which has been selected for measuring
- a stability indicator that shows that the moisture reading is stable
Then there are three buttons;
- the power button that turns the device on
- the power off button that turns the device off
- the grain selector button that circles through available commodities which can be tested with meter and allow you to select one
Finally, we have the male and female connector which make up the probe. The male connector connects the whole probe to the main unit (which is the meter) and the female connector receives the male end of the probe. This probe is what is inserted into a bag of grains to measure and indicate the current relative humidity around the grain in percentage.
How exactly does it work?
So we’ve figured out what moisture meters are in general and gone ahead to lower it down to the subject of this article; grain moisture meters. We know there are types; the pinless and pin grain moisture meters. We know an example of the pin grain moisture meter and how it even looks like. But how exactly do these grain moisture meters work?
Every moisture meter determines whether the grain is dry or wet by determining the resistance to the flow of electricity. We all know water is a conductor of electricity. Hence the more water in grain, the less the resistance, and the less water, the higher the resistance. This is then translated into readings in percentages.
The pinless grain moisture meter uses an electromagnetic pad, which when comes into contact with grains detects the moisture content by the resistance to the flow of electricity. It is either just dropped in a pile of grains or has a section that allows you to drop a few grains in for detection. Other pinless grain moisture meters crush the grains first to detect the moisture content.
However, the pin grain moisture meters like the GrainMate moisture meter require that you insert the probe or the pin part of the moisture meter into a pile of grains. The probe or pins then senses the conductivity to electricity in order to detect the moisture content of the grains.
The point is, grain moisture meters work by determining the resistance to the flow of electricity to detect the moisture content. The more moisture in grain, the lower the resistance, and the less water in grain, the higher the resistance.
Click here to find out the correct moisture readings for your grains