Wet holder for armature TA 32 To prevent solids in the liquid to be measured from drying on the pH-sensitive glass membrane and forming a solid crust, the pH electrode should always be kept wet. To prevent this if the liquid level is too low, a wet well is available for the TA32 immersion fittings. The advantage of the wet well is that it completely releases the measuring electrode for measurement when the liquid level is high enough.