pHionics Inc. articles

Introduction

Understanding factors affecting the accuracy of a measurement is essential to get the most value out of water quality sensors.  Once understood, then each of them can be accounted for by various means, either by the user or the sensor itself.

For pH measurements, temperature plays a large factor and can contribute to significant error if not understood and compensated for.  The rest of this article covers how temperature affects pH senso

There are two different methods of measuring pH currently available called potentiometric and photometric, with several different subsets of technologies for each.  This article focuses on the real-time monitoring capabilities of glass pH electrodes used in industrial process control, wastewater treatment, and environmental data logging and provides comparisons of common features to assist in purchasing the right electrode/sensor for your applicatio

Introduction

More goes into determining power requirements for water quality sensors than just the voltage requirement on the spec sheet.  An important, often overlooked factor is voltage drop on wires, which increases the longer they are.  While this is not a significant variable for standard cable lengths of 10-25 ft. (3.05-7.62 m), there are many applications requiring long cables (1000+ ft.) to reach underground or deep in a body of water.  In these

Before 4-20mA devices, pneumatic systems were the gold standard for analog process control in the early 20th century, using compressed air or unreactive gases to monitor various parameters such as temperature, humidity, tank levels etc. They could transmit signals relatively long distances, were inexpensive for the time, and had low flammability risks.  While the pneumatic techniques are still used today for certain applications, electrical analog signaling through current and voltage ha

Disclaimer: This article covers an equation for linear scaling of conductivity sensors to estimate salinity based on the Practical Salinity Scale of 1978 (PSS-78).  The equation effectively estimates seawater salinity between the practical salinity ranges of 22 and 42, temperatures 5-35°C, and pressure less than 200 dBar, using a temperature-compensated conductivity sensor.  This is not for use in any scientific literature but allows dataloggers and receivers wi

What is Dissolved Oxygen?

Dissolved oxygen is a measure of how many O₂ molecules are present in a liquid (most often water) at any given time.  It is incredibly important because oxygen sustains life in bodies of water and reduced dissolved oxygen levels can act as a warning for events that destroy ecosystems, such as algae blooms.   The units of measurement are typically mg/L or on a scale of 0-100% saturation.  The amount of dissolved

Our 3/4 inch Kynar® compression fitting (Part # cmp-k) is designed for long-term pipe mounting of pHionics STs Series™ sensors.  Mounting instructions are provided below.

The pHionics pHishgard™ is a device that easily slips over the electrode and provides additional protection from large fish scraping or otherwise damaging the electrode tip with their fins.  It works by expanding and contracting at the top via handles, similar to scissors. This allows the pHishgard™ to lock in the groove at the top of the sensor and stay securely in place when force is applied from any direction.