EN - Page 8
5.
Troubleshooting
Potential is not displayed correctly
Cause 1: poor contacting
Check the measuring cables on optical damages such as corrosion, cracks and
sessile plugs. Replace the cable.
Check the electrode with an external reference electrode, e.g. a calomel or silver
silver chloride electrode. (see 3. Checking the HydroFlex).
Cause 2: no or too little hydrogen production
Did you await the activation phase in water of 24 hours?
If not, wait 24 hours before you measure.
Is the duration of the cartridge exceeded?
If yes, please clean the hydrogen electrode as described above and replace the old
cartridge with a new one. The new cartridge also has to be activated before you
can use it.
Cause 3: slow ion exchange, e.g. when you switch from concentrated solutions to
weak concentrated solutions
Await the setting time, sometimes the balancing of concentrations lasts longer
than expected.
If necessary, check the potential in another electrolyte such as 1 mol/l
hydrochloric acid (see 3. Checking the HydroFlex).
Cause 4: air/oxygen gets to the electrode
Avoid that gases such as air or
oxygen reach the hydrogen electrode’s shaft. If this
happens the hydrogen is displaced or reacts off. No hydrogen potential can be set.
Fluctuating, noisy or oscillating potentials
Cause 1: hydrogen bubbles of the hydrogen electrode itself
Bubbles are continuously leaking out of the hydrogen electrode. Some bubbles are
small, others are bigger. Usually, they do not disturb your measurements.
Is a big bubble forming at the bottom of the hydrogen electrode which sticks to the
vessel wall? If possible, place the electrode further away from the vessel wall or
hang the hydrogen electrode transversely into the measuring vessel.
