How do you calibrate an EC-meter?

How do you calibrate an EC-meter?With the EC-meter you are able to measure the concentration of the total amount of dissolvable salt in a liquid. Therefore the EC-meter is an important tool to control and adjust the fertilizer strategy and the feeding schedule. After using the EC-meter for a longer period it is possible that because of filth and wearing of the electrodes a wrong measuring will occure. That’s why it’s important to regularly calibrate your EC-meter. When you do this you compare your measurement with the international standard values. But how does this work?

How often do you calibrate

De frequentie of calibrating is different for every company. Because it depends on how many times the EC-meter is used and the amount of filth in the EC-meter. The higher these numbers are, the more you need to calibrate. We advise that you calibrate your EC-meter a minimum of 2 times per month. It’s also wise to calibrate in the following situations:
  • When u use a new electrode
  • When the electrode hasn’t been used for a long time
  • After the electrode has been cleaned
  • When u used the meter in a powerfull solution
  • When it’s important to get a very exact measurement


A new electrode or one that hasn’t been used for a long time have to be cleaned first to get a good measurement.

Calibrating the EC-meter

For calibrating you choose the calibration with the value that comes closesd to the measurements that you see most often. In horticulture in most cases this is 12,84mS (an EC of 12,84). Use calibration liquid with every calibration.

Put the electrode in the calibration liquid. After about one minute the measuring is stable. De EC-meter is supposed to measure 12.840µS when you use 12,84mS of calibration liquid. If this is not the case then u set the EC-meter on this value (the further the measured value is away from the real value, the bigger the deviation of the device).

After calibrating you have to clean the electrode with deminalized water and place it in the calibration liquid again. Repeat these steps untill you get a reliable measurement.

Difference between calibrating and fine tuning

In most cases calibrating and fine tuning are being defined as the same. However these are two different things. With calibrating you define how far the EC-meter deflects from the standard. This is something you can do yourselve without concequences: u only set the accuracy of the instrument. Fine tuning is an official examination by a specialist who determines in what way the EC-meter satisfies to the legal prescriptions. When the EC-meter does not meet the legal prescriptions it will be disapproved and may not be used any longer.

Questions about EC-meter calibration

If you have any questions about calibrating our EC-meter, or would you like us to advise you? Please contact our produc specialist Nanne Bentvelzen our use the question form underneath.

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When you use the question form we will contact you as soon as possible. During working days we will contact you within 24 hours.

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