Before use it is recommended to place the electrode in pure de-ionised water and activate the electrode by recording a few minutes of data. This will clean the electrode from the previous use. If you get a high reading, replace the water and repeat. Watch out for glassware that has become contaminated from machine washing; dishwashers use high phosphate content cleaning agents and high alkalinity product.

Make sure the solution being measured covers the measurement cell, but do not immerse the whole electrode into the sample solution. The cable access point to the electrode has been made water resistant but it is not waterproof. Salt and brackish water are corrosive liquids; any ingress of the water into any of the electrode and / or sensor can seriously damage the product. This will not be covered by warranty.

The electrode has temperature compensation included, so as long as the measurement cell is fully submerged the compensation will be accurate.

When you have immersed the measurement cell into the water, gently tap or shake the electrode to disperse any air bubbles that may have formed on the electrode surface or lodged in the measurement cell (they will change the cell constant if left present).

Ideally use a sample bottle to remove the test water before sampling; dip sampling potentially lets bubbles and other sediments to interfere with accurate measurements. If a sample is taken it can be labelled and left to settle before the reading is taken.

If the recorded value is within the top 10% of the measurement range, change to a higher range or dilute the sample (after measuring with a dilution, remember to back calculate for the dilution to get to the real value).

Clean thoroughly before putting away.

The sensor can be calibrated against a known standard.

To make your own standards

Low standard

  • Dissolve 4.60 g of anhydrous, pure sodium chloride in enough distilled and de-ionised water to make 1.00 Litre of total solution volume. This will create a standard of 5.0 ppt 

High standard

  • Dissolve 9.20 pure anhydrous sodium chloride in enough distilled and de-ionised water to make a 1 litre solution. This will give a standard of 10 ppt.

Calibration requires you to open the devices in the software and follow the instructions.

This will be a one point calibration – all you need to do is tell the software that the reading you are showing is equal to the ppt of your solution.

Cleaning and maintenance

  • The sensor body is made of an epoxy based resin. It should be safe to clean with a non-polar solvent. 
  • Acetone / propanone will not be suitable. Check on a small section of the sensor body.
  • The detection cell can be cleaned by placing the electrode into de-ionised, distilled water and “recording for 20 minutes”. Replace the water half-way if necessary.
  • Blot the sensor dry to prevent dissolved solids appearing on the surfaces.
  • Limescale  / mineral deposits can be cleaned with 0.1 molar hydrochloric acid. It is not advised to soak in the acid for more than 5 minutes.