Tunze glass PH probe

[jauringer]

I was checking the calibration of my probe last night. It was perfectly calibrated, but it took about 5 minutes or more to finaly stop on 7 and 5. is that normal? the probe is about 1 week old.

 

[rvitko]

Don't do 5, 5 is for freshwater. If you need 9 let me know. It isn't a big deal, temp and other factors affect calibration. It sounds like it is OK and the 5 might have been a bit much for the probe to condition to after being in an alkaline environment.

 

[jauringer]

I am using the probe for my effluent. So, don't I have to use 5 since I am measering a PH of around 6.7

 

[rvitko]

Ah, yes. Well, all the same, don't worry about it. If it gives you trouble you know where I work, and I'll take care of it. The only thing I would add is make sure the electrode isn't submerged too deep. Only 2-3" should be submerged, otherwise water can enter the electrode and it will have to be flushed and filled.

 

[jauringer]

thanks Roger.

 

[blgreef]

Roger any details on how you can recharge a PH probe??

Have a Tunze thats old and no longer calibrates correctly

 

[rvitko]

If it is less than a couple years old this will work- order the 3molar KCL solution from Tunze, drain the electrode with a vacuum pump (aqualifter works OK for this.) With a small file carefully file the platinum tip (small speck on the side of the electrode, a couple strokes are sufficient). Clean the entire electrode with the electrode detergent from Tunze, being careful not to get any inside. Now, fill the electrode with new fluid and submerge it for 24 hrs with the fill port open to take in fluid.