Microwave moisture sensor for IQ Scanners

The Valmet IQ MW Moisture Measurement (IQ MW Moisture) is two-sided, non-contacting sensor that uses microwave resonance to measure moisture content for paper, board and pulp production.

Interference-free measurement

The Valmet IQ MW Moisture determines moisture content by measuring microwave resonance changes that are caused by moisture variation. This method is particularly well suited for heavy grades and multi-ply boards. The microwave energy penetrates through the entire sheet, measuring the moisture in all plies with equal sensitivity.

Neither web fluttering nor varying air humidity affects the IQ MW Moisture performance. Measurements remain unaffected by moisture stratification, freeness changes, sheet composition, or contaminants from recycled furnish. Temperature changes are also automatically compensated in the moisture readings.

Accuracy over a long lifetime

Utilizing an accurate and stable dual-resonance frequency measurement principal, the Valmet IQ MW Moisture provides a true total moisture reading, independent of moisture distribution in the sheet. One resonance frequency varies in proportion to the total moisture in the sheet. The second frequency, insensitive to the water, is used as a reference.

Advanced microwave technology enclosed in a robust, carefully engineered sensor ensure long-term accuracy with very low maintenance. A built-in dry air purge keeps humidity from accumulating in the sensor head. Possible dirt build-up is compensated by scheduled standardization checks.