Good timing for using needle type moisture meter and needle free moisture meter
In many cases, it may be necessary to test the moisture content (% MC) of certain substances. Moreover, when directly testing the moisture content of materials, there are two main options - needle water needle moisture meter and needle free moisture meter.
The needle moisture meter uses the principle of resistance to measure the moisture content in various materials. Due to the fact that water is a conductor, materials such as wood, cotton, gypsum, and hay are all resistors. The easier current flows through the material, the wetter it becomes. For the sake of precision, it is important to ensure that the needle instrument is calibrated for the specific material being tested - as different materials have different inherent current resistances.
On the other hand, needle less hygrometers use electromagnetic radio frequency to "scan" material samples to determine the presence of water. The fluctuation of electromagnetic waves is used to measure the amount of water in the sample. The accuracy of the needle free moisture meter is affected by the specific gravity (SG) of the scanned material, so it is necessary to calibrate the instrument for the SG value of that material. Specific gravity is a measure of the relative density of a material compared to another material (usually water).
Both needle type and needle free hygrometers have their unique advantages and disadvantages, which may make them more or less suitable for specific humidity testing situations. When should a needle type moisture meter be used and when should a needle free moisture meter be used? The following is a broad scenario, where one type of hygrometer may be better than the other.
Test a large and flat surface, such as the entire floor
The needle free moisture meter is skilled at quickly and effectively testing the moisture content of large areas of structures. Simply push the scanning board into the floor, read, lift, and repeat the scan in another position. The scanning board can inspect a large area at once, and each inspection only takes a few seconds. This allows users to quickly scan very large areas of the structure relatively easily.
On the other hand, a needle hygrometer can only check for moisture in the small area between the contact needles. In addition, they need to delve deeper into the tested material to obtain comprehensive reading. This usually means that greater force is needed to penetrate tougher materials, increasing the risk of strain and damage to the pins. A smaller testing area and additional effort can help increase the time and labor costs for measuring moisture on a large scale.
