Maintenance Overview
Clean Dry Air (2-3 PSI): Its is a must that all sensors have clean dry facility air connected to the air purge 1/4” NPT air fittings to keep the windows clean.
Hardware & Mounting: Ensure all hardware is in place and tight. Mounting of the units should be in a place that does not experience excessive vibrations.
Monthly Cleaning: It is recommended to perform monthly maintenance cleaning of the optical window using a dry rag to ensure no buildup.
The Solution
Multi-Point Moisture Monitoring & Calibration
Nine MoistTech sensors were installed across key points in the wood pellet production process, including green chips, four dryers, Lines 3A and 3B, finished pellets, and the dry hammer mill.
Each sensor was evaluated against laboratory moisture samples and calibrated or adjusted as needed. Where possible, multi-point calibrations were developed to improve measurement accuracy across the operating range. The onsite evaluation also identified maintenance, air-purge, and mounting issues affecting sensor performance
Installing the sensor is only part of the solution. Proper calibration, clean optics, air purge, and secure mounting are essential to accurate, reliable moisture measurement.
The Results
Improved Sensor Accuracy: Sensors were calibrated against laboratory samples, with corrected and multi-point calibrations applied where appropriate
Identified Accuracy Issues: Dust buildup, missing air purge, loose or missing hardware, and improper sensor positioning were identified as key causes of unreliable readings
Validated Best Practices: The dry hammer mill sensor—where the air purge was connected and operational—delivered the best results, reinforcing the importance of proper sensor maintenance and installation.
Clear Maintenance Plan: Monthly optical-window cleaning, clean dry air at 1–2 PSI, and secure mounting hardware were established as key recommendations for reliable ongoing measurement.
