9.Maintenance
Generally speaking, under normal operation, the transmitter needs no maintenance
except regular cleaning and calibration of the electrode to ensure accurate and stable
measurement and system operation.
The cleaning cycle for the electrode depends on the pollution degree of the
measurement sample. Normally, it is recommended to make weekly cleaning. The
following chart gives introductions of different cleaning methods according to different
type of contaminations to provide the operators with reference for cleaning and
maintenance.
Type of Contaminations Cleaning methods
Measuring solutions containing
proteins.炷Contamination of the
junction炸
The electrode should be soaked in PepsinİHCl for
several hours. METTLER-TOLEDO 9891 Electrode
Cleaner is recommended.
Measuring solution containing
sulfides.炷The junction becomes
black炸
The junction should be soaked in Thiourea/HCl
solution until being bleached. METTLER-TOLEDO
9892 Electrode Cleaner is recommended.
Contamination by grease or
organic substance
Short rinsing of the electrode with acetone and
ethanol.
Acid and alkaline soluble
contaminations
Rinsing the electrode with 0.1mol/l NaOH or 0.1mol/l
HCl for a few minutes.
Apply clean water to flash the electrode after above cleaning steps and immerse the
electrode in 3M KCl solution for 15 minutes at least, and then calibrate the electrode.
The electrode should only be rinsed and never rubbed or otherwise mechanically cleaned,
since this would lead to electrostatic charges. This could cause an increase in the response
time.
In cleaning the platinum electrode, the platinum ring of the electrode can be rubbed
gently with a wet soft piece of cloth.
䈜 The frequency of electrode cleaning depends on the type and degree of contamination.
However it is recommended that the electrode be cleaned once a week.
нт
To Next Page
Loading...
