System Fault
Sensor malfunctions that disrupt the measurement of liquid height in a dye or finishing chemical reservoir can cause severe process disruptions. A level transducer failure prevents the automated dosing system from maintaining the correct volume of liquor in the pad trough. This can lead to either the trough running dry or overflowing, both of which ruin the fabric being processed.
This fault must be detected and resolved immediately.
Process Impact
If the liquid level in the pad box drops too low, the fabric does not receive sufficient chemical treatment, resulting in pale or un-dyed patches. When a level transducer failure occurs, the dosing pump may receive incorrect signals to stop or run continuously. An run-away pump can overflow the trough, wasting expensive chemicals and creating a hazardous spill.
This also interrupts the continuous line, causing thermal damage to fabric stopped in the oven.
Diagnostic Method
Control systems use software algorithms to detect abnormal signals from the sensor, such as a frozen value or a rapid jump that is physically impossible. When the controller identifies a level transducer failure, it triggers an audible alarm and switches the dosing system to a manual or time-based fail-safe mode. Technical staff then inspect the probe for chemical buildup or electrical faults.
Cleaning the sensor often restores normal operation.
Redundancy System
Mechanical float switches are installed as a backup to prevent overflows. These simple devices cut power to the feed pumps if the liquid reaches a critical high level.
