Oven Drying Method

 

We recommend this for testing and calibrating of all electronic moisture meters. Short description:

• For measuring the weights we recommend a balance with a measuring range of 200g and an accuracy of 0,01g
• For drying you need an oven with adjustable temperatures of  40, 102, 104 and 105°C
• Take a probe from wood with a sharp saw, avoid edge parts. For building materials take a probe with a sharp chisel to a depth of approx 3cm. the probe should be at least 20g
• It is very important to take the weight of the first probe immediately, as air humidity may change the moisture content. Name of the first weight: wet weight (WW)
• The probe must be dryed in the oven until the weight is constant, drying temperatures:
  wood (ISO 3130-1975)  104°C 
  paper and cardoard (DIN EN 29287)  105°C
  concrete flooring, our reccomendation: 50°C
  leather (DIN 53340): 102°C 

• the weight of the dried probe: dry weight (DW)
  
  
• moisture calculation formulas:
  wood (ISO 3130-1975):                     moisture = 100% x (WW - DW) / DW
  moisture content in wooden chips: moisture = 100% x (WW - DW) / WW
  building materials:                             moisture = 100% x (WW - DW) / WW 
  paper ad cardboard (DIN EN 20287): moisture = 100% x (WW - DW) / WW 
  leather (DIN 53304):                         moisture = 100% x (WW - DW) / WW