HM Digital COM-100 multimeter (conductivity)

This parameter is part of the newly defined UK National Protocol as part of CaSTCo. This description is preliminary and will be updated shortly.

Measuring the electrical conductivity would normally happen along with making a temperature measurement.

Once the temperature measurement has stabilised the conductivity reading will also have stabilised and can be recorded. Check that the unit is ‘µS’ and that it is above zero. River water will never have a conductivity of zero – if your meter is reading zero then it may be faulty or the probe is in air. This may be because you did not remove the cap, or perhaps the ‘Hold’ button did not register properly.

When you have completed the temperature and conductivity readings turn the meter off, shake of any excess water and replace the cap.