ORP Sensor: How Does It Work And Why Is It Important?

Oxidation Reduction Potential (ORP) tells you exactly how clean the water is, which is highly useful for homeowners who wish to sterilise their pool water or wastewater treatment plants seeking to cleanse the water. You may use an ORP sensor to determine the amount of ORP in your water, which will immediately inform you how efficient your disinfectant and sanitary processes are.

Both reduction and oxidation are chemical reactions that involve the exchange of electrons across molecules. As a result, ORP assesses the likelihood of such reactions occurring in your water. In the pool sector, the greater the oxidation potential, the more effective your sanitiser, which results in cleaner, safer water.

Furthermore, a probe is used to test ORP in a tiny sample of flowing water, generally near your chemical regulator. An ORP sensor comprises two electrodes: an ORP electrode and a reference electrode. Effectively, a signal is passed between them, determining your reduction and capacity. The electron transport rate is measured in millivolts and denoted by the symbol ORP. The greater the ORP, the better, and most health agencies in the United States define 650mV as the minimum permissible ORP, with anything over 800mV being ideal. Anything over 850mV is considered outstanding water. Keep reading more about ORP.

What Is The Purpose Of ORP?

ORP, as said before, is a measurement that shows how well a single molecule can oxidise other molecules. It is often used to assess the efficacy of chemical disinfectants, the most common of which is chlorine. When chlorine is added to a contaminated pool, the chlorine should remove the impurities and ultimately evaporate. Chlorine is an oxidant, which implies it removes electrons from the cell walls of some bacteria. Readings from an ORP sensor may assist you in determining if the chlorine or equivalent disinfectant is operating correctly.

ORP may measure the whole chemical activity of a solution, including all reducing and oxidising disinfectants, regardless of the kind of solution used. Sodium Hypochlorite, Mono-Chloramine Hypochlorous acid, peracetic acid and ozone are the disinfectants used. If the disinfectant in question acts by reduction and oxidation, an ORP sensor will indeed be able to determine its effectiveness. In contrast, it can’t be utilised to identify a specific chemical in water unless the chemical causes a response. Additional sensors may be required to determine the percentage of a chemical in the water. ORP sensors will only notify you if the chemical is working correctly.

How Is ORP Measured?

A two-probed sensor immersed in a running water sample is used to measure ORP. The sensor measures the electric differences between the two probes. Also, the cleanliness of the probes might alter these findings; this is another factor to consider adding enzymes to your water. It also pertains to the system’s other probes, like chlorine probes.

Pool With High Chlorine But Low ORP

pH and organic pollution are the two most probable causes. The higher the organic content of the water, the weaker the conduction between the probes. Most controllers also monitor pH, so they will determine whether pH is the issue. If the pH is normal, organic waste is most likely the source of the problem.

Pool With Low Chlorine But High ORP

Either your probes aren’t working correctly, or you have excellent water quality. It’s unusual, but it’s not impossible. A sizeable commercial pool in Arizona, for example, has been capable of keeping 750 ORP while having less than 1 ppm chlorine. The pool was efficiently oxidising even with a somewhat high pH.

ORP Levels: High vs. Low

As explained previously, high ORP levels suggest that chlorine effectively cleans the water. While the quantity of chlorine added to the water is vital, the essential component of disinfecting water is ensuring that the chlorine is operating correctly. If you test the ORP levels in your water and find that they are low, this suggests that there are a lot of toxins in the water.

When sanitising water, the ORP measurement you’re given should range from 650mv to 800mv. Maintaining ideal ORP levels is critical to ensure that the disinfection is working correctly.

Variables Influencing ORP Measurement

ORP measures are affected by four unique variables: pH levels, the amount of phosphate, cyanuric acid, and water temperature. You ought to achieve a more exact ORP measurement if you keep these considerations in mind. The distinction between high and low ORP measures is that high values indicate better water quality.

If you use chlorine to sanitise the water in your swimming pool, the ORP sensor will inform you how efficient the chlorine is. High ORP levels suggest that chlorine effectively disinfects and removes contaminants from the water. If you’re still obtaining low readings even after adding chlorine, it’s conceivable that the sensor is broken or that one of the factors mentioned above is interfering with the measurement.

Now that you know why the ORP sensor is used and how it works, you must easily detect chlorine levels in the water while also assessing how successful the chlorine has been at cleaning the water.