1. Equipment fails to start or power is unresponsive
Inspection Steps:
Confirm the power cord is securely connected and the socket is supplying power normally.
Check if the fuse is blown and if the indicator light is on.
If the circuit is normal, check if the connection between the gear shaft and the piston push shaft is interrupted and if the threaded interface is loose.
Quick Solution: Reinstall the connecting parts or replace the piston push shaft.
2. Uneven or inaccurate dripping
Troubleshooting Direction:
Check if the drip head is clogged or the needle tip is worn, especially after using high-viscosity liquids where solidified residue may remain.
Observe if the air pressure is stable (applicable to pneumatic equipment) and if the piston movement is smooth.
Verification Method: Perform a no-load test, record the liquid output multiple times, and determine if the repeatability error exceeds the standard.
3. Air bubbles in the burette or liquid path
Impact: Causes inaccurate titration volume and measurement deviation.
Troubleshooting Methods:
Set the titration switch on the DZ to "Manual," adjust the three-way valve handle to the left, and set the DC switch to "Intermittent" mode.
Continuously press and hold the manual button to expel air until all air bubbles are expelled.
Preventive Measures: Regularly check that the connecting nuts between the suction tubing, infusion tubing, and three-way valve are tightened.
4. Unstable Millivoltmeter Pointer Swing (For Potentiometric Titrators)
Initial Diagnosis:
Check that the external wiring of the indicating electrode and reference electrode is intact.
Remove the reference electrode and observe if the pointer still swings.
In-depth Testing: Use a digital multimeter set to the 2K range to test the resistance of the Y-connection. If there is no reading, it indicates that the electrode connection is broken and a new connection needs to be replaced.
5. Flow Obstruction When Refilling Titrant
Key Inspection Points:
Check if the burette is functioning properly and whether it is aged or cracked.
Check that the connecting nuts between the suction tubing, infusion tubing, and three-way valve are secure.
Check if the burette sealing ring is tightened and if the DQ clamping screw is working properly.
Final Solution: If the above is ineffective, replace the burette assembly.
6. Self-flowing phenomenon (dripping continues after shutdown)
Common causes: The solenoid valve is not closing tightly; the rubber tubing is deformed or improperly installed.
The support screw is improperly adjusted, causing the valve to not seal completely.
Solution: Adjust the solenoid valve support screw to the appropriate tightness.
Disassemble the solenoid valve, adjust the vertical position of the rubber tubing, or replace it with a new tubing (it is recommended to soften it by boiling it in an alkaline solution for several hours first).
