Common faults and treatment of pH meter
Fault phenomenon pH meter fault cause pH meter fault treatment method
Indication fluctuates Pressure and flow rate of the measured solution change too quickly Check the status of the measured solution and adjust if necessary
The glass pH electrode is contaminated or the salt bridge is blocked Clean the glass pH electrode or clean the salt bridge, if still unable to measure, replace
Poor insulation of the measuring line Clean and dry the cable terminals
Slow response Slow displacement of test solution Check condition of test solution and correct if necessary
The glass pH electrode is not fully soaked Re-soak the glass pH electrode until it works normally
Contaminated glass pH electrode or blocked salt bridge Re-soak glass pH electrode or clean salt bridge, replace if no measurement possible
The indicated value drifts slowly in one direction. The bulb of the glass pH electrode has micropores or cracks. Replace the glass pH electrode.
The KCL solution of the reference pH electrode seeps out too quickly Replace the reference pH electrode
There are bubbles in the reference pH electrode Check and add KCL solution and remove the bubbles
The soaking time of the new pH electrode is not enough Re-soak the pH electrode for more than 24 hours
Indicated value runs to maximum Insulation damage around pH electrode chamber Dry pH electrode chamber, if O-ring is damaged, replace it with a spare
The glass pH electrode is damaged Replace the glass pH electrode
Reduce the insulation resistance of the measured line Clean and dry the cable terminals to make the insulation resistance greater than 1012Ω
There are obvious measurement errors. The measured solution, pressure and flow rate do not meet the working conditions of the pH electrode. The pressure of the pressurized KCL storage bottle does not meet the requirements. Check the state of the measured solution and the pressure of the pressurized KCL storage bottle. If necessary, adjust the which meets the requirements
The glass pH electrode is polluted or the salt bridge is blocked. Clean the glass pH electrode or clean the salt bridge. If it still cannot measure, replace it.
Poor insulation around pH electrode chamber Dry glass pH electrode, if O-ring is damaged, replace with spare
The characteristics of the glass pH electrode have deteriorated Replace the glass pH electrode and then calibrate with a buffer solution
The change of the solution concentration in the reference pH electrode For the refillable sensitive element, replace the internal solution, and for the full-filled sensitive element, clean the sensitive interior and fill it with KCL solution
The pH transmitter line is abnormal, repair or replace the amplifier of the transmitter
The reference pH electrode is damaged Replace the reference pH electrode
Wrong wiring of the cable and poor contact of the connector Check the condition of the connector in the junction box against the wiring diagram
Inappropriate grounding wire Check and replace the grounding wire or grounding point
Open circuit or short circuit of temperature compensation resistor Repair or replace temperature compensation pH electrode
