Sensor Integration
Measurement of acidity in wet processing baths is conducted using a single sensor that houses both the sensing and reference elements. A standard glass combination electrode combines the hydrogen-ion sensitive glass bulb and the reference chamber into one coaxial body. This design simplifies pH monitoring in dyeing and finishing machinery.
Potential Difference
The probe works by generating a millivolt signal across the thin glass membrane at the tip. This potential is compared to the stable potential of the internal reference electrode, which is in contact with the solution through a ceramic junction. The difference in potential is proportional to the concentration of hydrogen ions in the bath.
Electrode Maintenance
Keeping the probe hydrated is essential for maintaining the sensitivity of the outer gel layer of the glass bulb. Technical staff store the probe in a concentrated potassium chloride solution to prevent the reference electrolyte from leaching. Regular cleaning with dilute acid removes dye or surfactant residue that accumulates during bath testing.
Process Limit
High temperatures and strong alkaline conditions in cotton scouring baths accelerate the dissolution of the sensitive glass. Under these harsh conditions, the probe’s response time slows and the electrode undergoes rapid degradation. Consequently, the electrode requires frequent replacement when used continuously in high-temperature preparation processes.
