eutech-instruments cyberscan ph 110 phmvrs232 meter User Manual

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Instruction Manual   
 
CyberScan pH 11 / 110  
 
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rejuvenate it. (See section 11.4 on Rejuvenation Procedure). 
11.2 Electrode 
Cleaning 
Electrodes that are mechanically intact can be restored to normal performance by 
one or combination of the following procedures. 
a) Salt deposits: 
Dissolve the deposit by immersing the electrode in tap water for ten to fifteen 
minutes. Then thoroughly rinse with deionised water. 
b) Oil / Grease Films: 
Wash electrode pH bulb in a little detergent and water. Rinse electrode tip with 
deionised water.  
c) Clogged Reference Junction: 
Heat a dilute KCl solution to 60-80 °C. Place the sensing portion of the pH 
electrode into the heated KCl solution for approximately 10 minutes. Allow the 
electrode to cool while immersed in some unheated KCl solution. 
d) Protein Deposits: 
Prepare a 1% pepsin solution in 0.1M HCl. Allow the electrode to stand in this 
solution for five to ten minutes. Rinse the electrode with deionised water.  
11.3 Electrode 
Activation 
Generally, if the procedure of storage and maintenance had been closely followed, 
the electrode can be used immediately. However, should the electrode response 
become sluggish, it may be possible that the bulb has dehydrated. The bulb can be 
re-hydrated by immersing the electrode in an ideal storage solution (e.g. buffer pH 4 
solution) for 10 to 30 minutes. If this fails, the electrode may require re-activation. 
At no time should one touch or rub the glass bulb as this causes the build-up of 
electrostatic charge. 
If the above procedure does not re-activate the electrode to acceptable status, try 
rejuvenating the electrode by following the procedure outlined below.