Page 83 - PBL71 OI/AXM630-EN AZTEC 600 SS (WIRO)

Aztec 600 ISE ammonia and fluoride
Single-stream ion-selective analyzers Appendix B – Troubleshooting
Fault
Possible Cause
Remedy
Low readings
Incorrect calibration
Check calibration solutions for accuracy
Ammonia probe response slow
1. Check probe and replace membrane if required
2. Check reference electrode for signs of stripping of chloridised layer
Calibration values incorrectly input into configuration
Check calibration input values and calibration solutions value. Use mV Offset to give indication – the further from 0mV, the more likely it is that the standard values are different to the true standard concentrations
Ammonia stripping in tubing and instrument feed lines
Check for contamination in all tubing and feed lines – clean or replace as required
Sample contaminated
Take appropriate measures to ensure the sample is suitable for measurement
Calibration failure
Calibration failure with low Gradient Coefficient or
% Slope indication
Calibration failure with High Gradient Coefficient or
% Slope indication
Incorrect calibration solution value(s) entered in configuration
Enter correct value
Incorrect calibration solution(s)
Check quality – replace / remake if necessary
Insufficient / incorrect calibration solution supply
1. Check valve manifold fluid connections
2. Check valve electrical connections
3. Check calibration solution levels and refill if required
4. Check tubing for blockages
5. Check pump speed and pump tubing for wear
Insufficient or incorrect reagent
Check levels and quality – replace if required
Faulty probe
Ammonia
& – Check end of probe is clear of any possible fouling Fluoride
Fluoride – Replace membrane and recalibrate
Incorrect calibration solution(s)
As above
Insufficient / incorrect calibration solution supply
As above
Insufficient or incorrect reagent
As above
Faulty probe
As above
Electrode insensitive
Ammonia – Replace membrane – if symptom resists, replace probe. See also 'Calibration failure' remedies
Fluoride – Replace probe. See also 'Calibration failure' remedies
Incorrect calibration solution(s)
As above
Insufficient / incorrect calibration solution supply
As above
Table B.1 Faults, Causes and Suggested Remedies (Continued)
OI/AXM630–EN Rev. J 79